Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
VETERINARY MEDICAL NURSING 1 Version 9.1 1 Introduction 2 Applied Vocational Training Veterinary Medical Nursing 1 Introduction This module is designed to provide veterinary nursing students with a knowledge of Veterinary Medical Nursing. Topics discussed include: Identify characteristics of healthy and unhealthy animals, record and report signs of ill health Provide basic information to clients on the causes of disease and how diseases may be transmitted, prevented and the risk of zoonoses. Maintain and provide assistance to the veterinarian in the consulting room. Perform basic medical nursing tasks Identify situations requiring emergency treatment and administer routine first aid Assist the veterinarian with euthanasia and disposal Text Books / Equipment Students will need to purchase or have access to a stethoscope and thermometer Useful Reading Saunders Comprehensive Veterinary Dictionary 4th Ed (2012) D.C. Blood & V.P. Studdert Harcourt Brace & Company Ltd., London BSAVA Textbook of Veterinary Nursing 5th Ed(2011) Lane, Cooper and Turner Clinical Textbook for Veterinary Technicians 7th Ed (2010), D. Mc Curnin, W.B. Saunders, Pennsylvania. Nominal Study time 24 hours Learners who believe they may already possess the knowledge and / or skills described, may be able to obtain credit for this unit. You should discuss with your lecturer the process of Recognition of Prior Learning (RPL) Photo on cover: note some reddening on the tip of nose indicates inflammation. Image: Vera Kratochvil 3 Applied Vocational Training Veterinary Medical Nursing 1 Introduction 4 Applied Vocational Training Veterinary Medical Nursing 1 Introduction Module Instructions 1. Read the module material. 2. Complete any exercises required 3. Complete any assessments and submit to tutor Should you need any help or explanation, please contact one of the AVT staff by email or telephone. Mailing Address: Visit our Training Centre at: Applied Vocational Training PO Box 1520 Canning Vale Business Centre Western Australia 6970 Applied Vocational Training Unit 18, 87 - 91 Catalano Circuit Canning Vale, Western Australia Telephone: Fax: (08) 9456 1060 (08) 63130662 Web: www.appvoc.com Please see our website for directions (618) 9456 1060 (Outside Australia) (618) 63130662 (Outside Australia) Email: [email protected] 5 Applied Vocational Training Veterinary Medical Nursing 1 Introduction 6 Applied Vocational Training Veterinary Medical Nursing 1 Introduction CONTENTS Chapter 1 Characteristics of healthy and Page 11 unhealthy animals Chapter 2 Chapter 3 Cause, transmission and diagnosis of Page 57 disease Diagnosis of Disease/ The animal’s Page 99 response to disease Chapter 4 Treatment and prevention of disease Chapter 5 Medical Nursing tasks Page 131 Page 167 ASSESSMENT To complete this module, you need to have submitted the assessments listed below. Please fill in the details as your record of progress in this module. Assessments are in the form of tests Assessment Contents Assessment 1 Chapter 1 Assessment 2 Chapter 2 Assessment 3 Chapter 3 Assessment 4 Chapter 4 Assessment 5 Chapter 5 Date when sent Date Received back 7 Applied Vocational Training Veterinary Medical Nursing 1 Introduction 8 Applied Vocational Training Veterinary Medical Nursing 1 Introduction INSTRUCTIONS FOR ASSESSMENTS Revision and assessments for this module can be divided into two: Worksheets Assessments Worksheets At the completion of each chapter you need to answer the worksheets at the end of each chapter. These worksheets are designed to assist you with your revision. All worksheets should be completed prior to attending to the assessments in this section. Normally you DO NOT need to submit the worksheets, however occasionally you may be asked to do so by your tutor. Assessments Assessments are the mainly in the form of short tests. For correspondence students these assessments will be sent to your mentor or be available as a download. For each chapter there is a corresponding assessment .All of these assessments must be satisfactorily completed and submitted for marking. Submitting Assessments for Marking By Email Use Contents All Students Email to Australian and [email protected] Overseas Marked assessments returned via email will be will be By Mail Australian Students only Post to address shown Marked assessments on page 5 returned via the post Drop in to our Training Centre Australian Students only Post to address shown Collect from our centre when on page 5 marked or they will be posted By Fax Australian Students only Fax to number shown Our least favourite method of on page 5 receiving marking (faxes never seem to be reliable) Use for emergency only. Marked assessments returned via the post will be We attempt to mark all assessments within 7 days of them being received. Delays may occur during term breaks and holiday periods 9 Applied Vocational Training Veterinary Medical Nursing 1 Introduction PLEASE ENSURE THAT ON EACH ASSESSMENT SENT IN YOU WRITE: YOUR NAME AND ADDRESS and THE MODULE AND ASSESSMENT NUMBER Assessments are graded as a “pass” if all requirements are met, or “ hold” if further work is needed to meet the standard required. Where appropriate a grade will be applied to indicate your level of achievement, however the pass mark for most assessments will be 70 %. You are required to pass all assessments to pass this module. When an assessment is due, it will be indicated as shown Please complete and submit Assessment Now 10 Applied Vocational Training Veterinary Medical Nursing 1 Introduction CHAPTER 1 Characteristics of Healthy & Unhealthy Animals Outline Identify characteristics of healthy and unhealthy animals Measure and record temperature, pulse and respiratory rate Recognise when veterinary attention is necessary Instructions for this chapter Complete all questions and exercises found in this chapter using your notes and information you might research elsewhere. Assessment for this chapter Complete and send in Assessment 1 11 Applied Vocational Training Veterinary Medical Nursing 1 Introduction 12 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Chapter One Outline Healthy Animals Health Physical signs Physiological signs Behavioural signs Assessing the Health of Animals Disease History Distant Examination Close Examination Temperature Pulse Respiration Mucous membrane Ancillary tests When should an animal receive Veterinary attention? 13 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 14 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 HEALTHY ANIMALS We often identify animals that are unwell, but how do we actually do this? What are the signs that indicate that an animal is not in a normal healthy state? To appreciate fully an animal’s health status, it is useful to first look carefully at the indications or signs of a healthy animal. Take a few minutes to consider some signs that an animal is in good health. It may be difficult to come up with the ten answers to the study questions, probably because we tend not to note the signs of good health, but rather notice the signs of poor health, when there is some problem with the animal. Exercise Consider a healthy animal that you know or have known. Make a list of at least ten signs that indicate this animal’s good health. Normal appetite and bright eyes might be two examples. You do not need to send study questions to your teacher. ________________________________ _________________________________ ________________________________ _________________________________ ________________________________ _________________________________ ________________________________ _________________________________ ________________________________ _________________________________ 15 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Looking at a definition of health, and an approach to detecting signs of health can be useful. Several definitions exist, two that are commonly used are mentioned below. Health = A state of physical, mental and social well-being. Health = Free from disease. One method of looking at the signs of health (or disease) in animals is to consider: Physical signs Physiological signs Behavioural signs Physical signs These are signs associated with body structure and appearance. Some examples are: Good body condition Normal movement No abnormal lumps Glossy coat Skin free from parasites No abnormal odours or discharges Physiological signs These are signs associated with bodily functions and include : Normal eating and drinking Normal temperature, pulse and respiration Normal defaecation ( passing faeces ) and urination Normal mucous membrane colour ( gums, conjunctiva etc) Usual reproductive cycles. 16 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Behavioural signs These are the signs of how an animal relates with other animals and people. Of course different species of animals will have different normal behaviour. Some examples of normal behaviour include: Normal social interaction with other animals and people Lack of excessive aggression Normal sexual and mating behaviour Lack of vices ( excesses of behaviour such as wind sucking in horses, or tail chasing in dogs ) When recording a sign, use the term normal or usual. For example recording appetite as a sign of good health is not an adequate description, does it mean good appetite, no appetite, excessive appetite??? Normal/good appetite is the proper description. A discharge from a female animal in oestrus (heat) is a normal healthy occurrence, in cases like this, the proper terminology would be to record no abnormal discharges. Not all smells are abnormal!!! 17 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 ASSESSING THE HEALTH OF ANIMALS DISEASE Ill health or disease represents a change to the normal healthy signs of an animal that we have already discussed. Various definitions of disease can be found, and they may be quite broad. They include: Disease = Any departure from normal health. Disease = Abnormality of structure and function. Usually a disease will have a recognisable set of signs or abnormalities that indicate a particular condition. Some diseases are quite easy to recognise, for instance a common respiratory virus (colds and flu), a broken leg, or flea infestation. Other conditions are less easy to classify as a disease. For example: Is a pet dog that refuses to mate, suffering from a disease? Is a cow that produces less than the normal amount of milk, suffering from a disease? The answer doesn’t really matter. The definition is only academic, and it is clear that whether a broken leg, or a failure to reproduce, that it is a departure from normal health. To be thorough, a systematic approach to the determination of an animal’s health should be used. Systematic Approach History Distance Examination Close Examination Ancillary Tests 18 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 HISTORY Taking a history refers to obtaining information about the animal and recording this information in a suitable format. It should be the first step in any assessment of an animal’s health status and should include details that enable identification of the animal, details of its present health status, and any relevant details of its past health. A history can be taken without actually examining the animal, and should be done prior to any examination. Animal’s details Information such as name of the animal and its owner’s details Species, breed, sex, age, Recent information General attitude (is the animal bright and alert?) Eating, drinking, urination, defaecation, Tolerance to exercise. Has the animal had contact with any new animals, or travelled away from its usual home? Past information Is the animal sterilised? Has it been vaccinated? Has it been treated for parasites? Any significant past illnesses. Any major illnesses of parents, if known. Information on current problems What are the signs of any current problems? How long have these problems been evident? Are they improving, not changing, or are they getting worse? Are any other animals affected with this problem? The above questions are only a few of the possible questions that could be considered and are intended to act as a guide to obtaining a reasonable history. Each piece of data may provide valuable information about an animal’s health. In the case of a problem, the information will assist in determining the particular problem and its likely outcome. 19 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 A few examples of how the information may be used include: Unvaccinated animals may need vaccination. Diseases of young animals may be different to that of older animals. Sterilised animals are less likely to have diseases of the reproductive tract. Some diseases are inherited from the parents. A comprehensive medical record includes many details 20 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 DISTANT EXAMINATION This is the next process, following the taking of a detailed history. It is used to gain information on the current status of the animal and should be done by looking at the animal, but not actually touching it. The closeness to the animal will vary with the species: (a cow in a paddock, or bird in an aviary or perhaps a cat on the sofa). You should be close enough to observe details of its condition and awareness, but far enough away to observe its movement and behaviour. Healthy appearance for a Cavalier King Charles Spaniel. Image yourpurebreedpuppy Many of your observations will mirror those of the history, but often the history will be presented by someone other than yourself (the owner or carer if it is not your own). The examination is important to determine the current state of the animal. Some information that may be obtained from a distance examination include: Alertness Posture Body condition Behaviour Appearance of skin or coat Any abnormal features Abnormal lumps Breathing Discharges Movement 21 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 It is important to be aware of normal behaviour in a particular species of animal before you can make a judgement about it. Animal behaviour is discussed a little later in this module relating to animal handling and is discussed in more detail in the Animal Behaviour module. Some behaviour is similar in all species, for instance normal appetite and normal drinking. Aggressive behaviour towards other individuals may be normal in some species but is considered abnormal in others. The animal may be ‘divided’ into different areas, all of which can be examined during a distant examination. Behaviour SIGNS OF HEALTH SIGNS OF ILL-HEALTH Alert Lethargic Bright Depressed Interested in surroundings Reluctance to move Responds to external stimuli Change in temperament Interacting with other animals Aggressive towards others, hiding in a corner Posture Free head movement Stiff neck Can stand on all feet evenly Hunched up Straight back Tail hanging unmoving Free tail movement Difficulty sitting or lying ‘Praying’ position – rear in air, elbows and chest on ground Gait Smooth and flowing movement Lameness or limping Weakness in limbs Trembling Reluctance to move at all 22 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Ears Symmetrical in shape Any discharge Pricked Smell Clean Swollen flap Respond to sound Head to one side Ear/s drooped Scratching or rubbing at Redness Eyes Bright Discharge Clear Cloudiness Open (if awake!) Redness Even shape and size Pupils uneven size No marks on eyeball Eyeball or eye area swollen Dullness Glassy One closed Respiration Regular breathing Difficulty breathing Nose looks moist Panting unnecessarily No nasal discharge Nasal discharge Crustiness around nose Coughing and/or sneezing Chest sounds such as crackling or wheezing Fast / slow / shallow / deep breathing Skin / coat Evenly covered coat Patches of hair loss Smooth coat Flaky / crusty / scabby skin Glossy coat Change in pigmentation Coat lying flat (if applicable) Dry or greasy skin / coat Excessive scratching Smelly skin / coat 23 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Urinary system Urine is clear pale yellow Frequent urination Passing urine with ease Difficulty in urinating Cloudy or bloody urine Change in volume of urine Change in drinking habits Strong smell to urine Change in colour Limbs Symmetrical Any swelling All held evenly Held at unusual angle Asymmetry Muscle wasting Not using Digestive system Normal faeces Excessive vomiting Regular defaecation with ease Diarrhoea / constipation Normal appetite Increased volume of faeces Abdominal ‘noises’ Flatulence Not eating and / or drinking Excessive salivation Mouth odour Ravenous appetite Under / over weight Unexplained weight change It is important to realise that the signs listed above are only very general signs and may not apply to all animals. As mentioned previously, it is very important that the comparisons take place with the animal in a normal state. If a Basset Hound pricked its ears up in the air, although pricked ears are listed as a sign of health, it would in this case definitely be a sign of ill-health as it would be abnormal (besides looking quite silly!). 24 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 So although these signs can be used as a guide for considering ill-health they are just that – a guide. What would be considered normal for the particular breed would also need to be a factor of determination of health status. In looking at signs of health and ill-health, the changes are far more important than what is actually seen. For some of the signs listed above, it would be necessary to get quite close to the animal, but there would be no need to actually handle the animal. The amount of information that can be gathered just by observation should never be underestimated. This is particularly so if the animal is being observed in its normal habitat. Of course it may demonstrate some different signs, especially behavioural, if in a strange environment. The environment would then also need to be considered and it would be necessary to determine how much influence it is having on the animal. This can be very difficult to do. CLOSE EXAMINATION This is the stage at which the animal would be physically examined. A ‘hands on’ examination would be done. The animal would be felt all over and any areas of concern examined particularly thoroughly. The type of information that could be determined from this type of examination is: Detection of internal swellings Detection of painful areas Areas of discomfort – the animal may groan when the abdomen is touched indicating an abdominal problem for instance. Temperature, Pulse, heart and respiration rates Heart and respiration rhythm Mucous membrane colour and capillary refill time Normality or abnormality of internal structures 25 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Many different approaches exist, one useful and common one has the following components: 1. Hands on examination of animal 2. Temperature, Pulse, Respiration Physical examination involving hands – on approach. Image pictrough Hands-on examination of animal Here the animal is felt and examined carefully from head to toe, noting any abnormalities. On the head: ears, eyes, mouth and teeth are all carefully examined for abnormalities. The rest of the animal down to the tail, including the legs are carefully examined. Many abnormalities can exist, examples of a few that might be detected are: poor teeth eye defects discharge from ears sore neck mites living in hair lump on chest abdominal pain lump in mammary area absence of one testis blood around anus swollen foot 26 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 All abnormalities should be recorded. Of course, not all abnormalities found will be significant. For instance an animal may have a lump on its leg that was caused by a bump several years ago, and now causes no problems. TEMPERATURE, PULSE, RESPIRATION These measurements can provide very important information about the health of an animal, and form part of a routine health examination. TEMPERATURE Animals have a very well defined normal body temperature range. Some temperatures for various species are shown in the table below. Species Temperature(0C) Dog 38.3 – 39.2 Cat 38 - 39.2 Horse 37.2 - 38.6 Goat 38.5 - 40.5 These temperatures are for adult animals at rest. A temperature that is outside of the normal range may be caused by many events, some of them quite normal and not associated with disease. Some normal events that may cause an elevation in temperature include high ambient temperature ( hot day ) excitement exercise nervousness 27 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Some conditions that might change an animal’s body temperature include: High body temperature Low body temperature Infections Shock Heat stroke Hypothermia ( exposure to cold ) Pain Severe disease Inflammation Anaesthesia Convulsion Poisoning Fever is also known as pyrexia ( or being febrile) and refers to an elevated temperature due to an infection or inflammation. There are many more examples that can be found. In the dog for instance, even with severe disease, the temperature rarely exceeds 41 o C or falls below 36 o C. An interesting situation may occur in the pregnant bitch just prior to giving birth, where the temperature falls up to two degrees. To Determine an Animal’s Temperature A standard mercury thermometer is usually used. These can take a little getting used to initially. A magnified view is shown below. 35 6 7 8 9 40 1 2 The mercury (the silver liquid in the bulb) will rise up the thermometer with heat. It will then stay in the position of the highest temperature. 28 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 35 6 The numerals indicate the degrees Celsius, and are further broken down in to tenths of a degree. The temperature is determined by reading the top of the mercury, which is a silver colour, against the blue or white background. Try reading the examples below and then practice with your own thermometer using warm water (under the tap) to change the readings. 35 6 7 8 9 40 1 2 35 6 7 8 9 40 1 2 35 6 7 8 9 40 1 2 The readings in the above case are 36.6o C , 40 .0 o C, 38.8 o C Remember to use the tenth of a degree scale, and report the temperature using tenths of a degree. 29 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 You may need to rotate the thermometer to be able to see the mercury properly. Many people in the community are used to reading thermometers. Doctors, dentists, vets, nurses and many mums. Ask for some help if you need it !!! To take an Animal’s Temperature The following photographs illustrate the method used for the dog. The same principles apply to all species Make sure the animal is properly restrained and you are in a safe position. ( Do not attempt to take the temperature of horses and farm animals unless you are experienced and familiar with the technique ) Shake the thermometer firmly by holding it with the thumb and first finger, a flicking motion is best ( imagine you are trying to shake a spider off your hand !!! ). This forces the mercury back towards the bulb, ensure the level is below 35 degrees. 30 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Lubricate the bottom half with vaseline, KY jelly, soap or oil. Insert the bulb end gently ( it may help to softly rotate the thermometer during insertion ) into the animals rectum. Insert a third to a half of the thermometer. Keep hold of the thermometer. Lubricate 35 Bulb 6 Insert up to here 7 8 9 40 1 2 Below 35 31 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Hold the thermometer in the rectum for about one minute, then gently remove it and wipe it clean with cotton wool, to remove any faecal material. Hold the thermometer up vertically and rotate until you can determine the reading. Write down the temperature. Clean the thermometer with cotton wool and cool water, and then clean with an antiseptic solution. Hibitane or other antiseptics are suitable. Store thermometer. Wash your hands. 32 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 PULSE The pulse of an animal is the rhythmic throb due to the beat of the heart that is felt through the wall of an artery. It is created by blood being forced through the arteries of the body, under pressure due to the contraction of the heart. Under most conditions, the pulse corresponds to the heart rate. That is: one contraction of the heart gives one pulse As with temperature, animals have a very well defined normal pulse. Some pulse rates of various species are shown in the table below. Species Pulse Beats / minute Dog 60 - 120 Cat 120 - 200 Horse 28 - 40 Goat 70 - 135 Usually the smaller the animal species, the faster the heart rate. These rates are for adult animals at rest. Younger animals will generally have a more rapid pulse . A pulse rate that is outside of the normal range may be caused by many events, some of them quite normal and not associated with disease. Some normal events that may cause an elevation in pulse rate include high ambient temperature ( hot day ) excitement exercise nervousness 33 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Some conditions that might change an animal’s heart rate include: Elevated heart rate Lowered heart rate Infections Sleep Fever Hypothermia ( exposure to cold ) Heart disease Unconsciousness Blood loss Anaesthesia Pain Severe shock Many other events can change the rate of the heart. Tachycardia is the term used to describe an abnormally fast heart rate. Bradycardia is the term used to describe an abnormally slow heart rate. Equally important in measuring the rate of the pulse, is the strength and rhythm of the pulse. Normally the pulse is strong, and an even rhythm is evident. It is normal for the pulse to increase slightly when an animal breathes in, and slow down slightly as an animal breathes out. This is described as sinus arrythmia and is a normal finding. In some diseases the strength and rhythm may change. For instance, shock is often characterised by a weak, irregular pulse. To measure the Animal’s Pulse or Heart Rate The usual method is to apply gentle, but firm pressure to an artery using the first two or three fingers of one hand. The number of pulsations is felt and counted for one minute and then recorded. 34 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 In small animals such as dogs, the best pulse is felt from the femoral artery which runs high up the inside of each of the back legs. Feeling femoral pulse in the hind limb and listening to heart beat with stethoscope. Image Long Beach Veterinary Hospital In larger animals various other locations may be used depending on the species. A horses pulse is best felt by pressing the submandibular artery underneath the mandible ( jaw ) on the head. It can be a difficult task to accomplish without some practical instruction and some practice. Should you not be able to take a pulse then get some help from a trained Veterinarian or Veterinary Nurse. A doctor or nurse should be able to show you how to determine the pulse in a human, which may give useful practice. 35 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 The other method of determining the heart rate is to directly listen to the heart. Listening to any internal body sounds is called auscultation. It may be done using your ear directly to the animal, but it is much easier to use a stethoscope. Earpiece Connecting Tubing Bell When using the stethoscope ensure that the large flat part of the bell is working. In models that have a large and small side to the bell, you may need to hold the metal attachment to the bell and rotate the bell until the flat white side is working. Place the bell firmly over the area of the heart on the left side of the animal. To do this you usually need to position the bell underneath and forward of the elbow onto the chest. If the sound is faint, you may need to push the bell a little further forward. Get some expert help if you need it !! 36 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Approximate position of heart When listening to the heart you will hear two heart sounds : lub ...dub These sounds correspond to the valves in the heart closing during ONE heart contraction. Therefore it is important to note that each two sounds are equivalent to one heart beat , not two beats. lub ...dub lub ...dub lub ...dub lub ...dub lub ...dub would represent 5 beats. Measure the number of beats for one minute and write this down. 37 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Listening to a dog’s heart Listening to a horse’s heart Study Exercise Determine the heart rate at rest of two people and two animals. Record these below. Get one of your subjects to undertake a brief session ( a few minutes ) of light exercise. Record the rates before and after exercise. Person 1 _____________________________ Person 2 _____________________________ Animal 1 Species ______________ Rate ______________ Animal 2 Species ______________ Rate ______________ Before exercise ________________ After exercise ______________ 38 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 RESPIRATION As with temperature and pulse, animals have a well-defined normal respiratory rate.. Some rates for various species are shown in the table below. A gentle rhythm is a normal feature of respiration Species Respiratory rate Breaths / minute Dog 10 - 30 Cat 20 - 40 Horse 10 - 14 Goat 15 - 25 Usually the smaller the species, the faster the respiratory rate. Note that the measurement is in breaths per minute. These are for adult animals at rest. Younger animals will usually have a higher respiratory rate. A rate that is outside of the normal range may be caused by many events, some of them quite normal and not associated with disease. Some normal events that may cause an increase in respiratory rate include high ambient temperature ( hot day ) excitement exercise nervousness 39 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Some conditions that might change an animal’s respiratory rate include: Increased respiratory rate Decreased respiratory rate Infections of respiratory tract Sleep Obstructions of respiratory tract Poisons Poisons Shock Heart disease Hypothermia ( exposure to cold ) Pain Severe disease Anaesthesia Many more examples can be found. Dyspnoea is the term used to describe difficult or laboured breathing. This is often associated with conditions such as an obstruction, pneumonia and heart disease. Rather than the smooth rhythm of normal respiration, the movement may be jerky and forced, even with the animal gasping for breath. Apnoea describes a cessation (stopping) breathing, and will result in death unless quickly reversed. To measure the Animals Respiratory Rate It may be done either by observation, or by placing a hand on the animals’ chest. It can be quite difficult on occasions, especially if the animal is moving. You should measure the number of breaths for one full minute. Record the values on a piece of paper. One full breath involves breathing in (the chest wall expands) breathing out (the chest wall deflates ) 40 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Breathing in Breathing out One full breath Study Exercise Determine the respiratory rate at rest of two people and two animals. Record these below. Get one of your subjects to undertake a brief session (a few minutes) of light exercise. Record the rates before and after exercise. Person 1 _____________________________ Person 2 _____________________________ Animal 1 Species _____________ Rate ______________ Animal 2 Species _____________ Rate ______________ Before exercise ________________ After exercise ______________ 41 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Some comments The ranges given for various species can be found in most books dealing specifically with that species. You may find that the ranges given may vary between books and from those given here. This is because they are an estimate, and an animal temperature pulse and respiration may vary within limits around the normal range. An animal’s TPR (temperature, pulse and respiration) will constantly vary within the normal range. For instance a temperature for a particular animal may measure 38.0 then when checked an hour later is 38.6. This is quite normal. A TPR provides very useful information about the health status of an animal, but is only used as part of a whole systematic examination in the determination of an animal’s health status. The following table collates the estimates for TPR ranges given above. Species Temperature o ( C) Pulse Respiratory (Beats / minute) rate (Breaths / minute) Dog 38.3 – 39.2 60 - 120 10 - 30 Cat 38 - 39.2 110 - 220 20 - 40 Horse 37.2 - 38.6 28 - 40 10 - 14 Goat 38.5 - 40.5 70 - 135 15 - 25 Animals do not get symptoms. A symptom is a perception of illness, for instance a headache, or feeling nauseous or dizzy. Animals may well feel that way, but they can’t tell us what they feel, so the term is not applicable to animals. The correct term for describing some problem, is a clinical sign or just sign. This is something that we can see or measure, such as vomiting or pain on palpation. 42 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 MUCOUS MEMBRANE COLOUR This is a ‘test’ that is often done while carrying out TPR readings. It is carried out simply by looking at the colour of the mucous membranes. The mucous membrane lines many of the hollow organs in the body as well as the whole of the digestive tract, urinary passages and the genital passages. The easiest place to assess it in the dog or cat is in the mouth (the gum colour) or the conjunctiva of the eye. The colour should be a light pink. It should not be too pale or too red. The capillary refill time can also be assessed very easily. The gum is simply pressed with a finger. The capillary refill time (CRT) is the time that it takes for the pink colour to return after removing finger pressure (which causes the patch of gum under the finger to go white). In healthy animals the CRT should be less than 1 second (which means the normal gum colour returns immediately). ANCILLARY TESTS It may be necessary to perform tests that provide further information about the health status of an animal. Of course, these tests will need to be conducted by a Veterinarian and are used in cases where more information is required to determine the nature of a problem. Usually these tests require the use of specialised equipment, and may involve samples from the animal being sent to a laboratory. Preparing to X-ray an animal. Image: Perth Veterinary Specialists A summary of some of the more common tests is given below: a general description of their use and a few common conditions that these tests may be useful for are described. 43 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 TESTS LABORATORY TECHNIQUES haematology clinical chemistry USE EXAMPLES to examine blood cells and blood composition determine levels of body chemicals cytology and histopathology looking at cells from the body clinical microbiology urinalysis cultivating microorgansisms that are found in or on an animal examining an animal’s urine clinical parasitology examining animal parasites DIAGNOSTIC IMAGING AND ELECTROCARDIOGRAPHY radiography taking radiographs using x rays diagnostic ultrasound using sound waves to determine body structures electrocardiography using an ECG machine to examine the heart’s function examining a dead animal to determine cause of death POST MORTEM EXAMINATION anaemia, heartworm disease, blood loss liver and kidney disease. muscle damage. reproductive status cancer diagnosis bacterial diseases viruses and fungi diabetes, kidney damage, dehydration worm eggs in faeces skin parasites fractures, bowel obstructions, bladder disease. pregnancy diagnosis. bladder and kidney disease. heart disease heart failure The above list is not a complete one, and only a few examples of the use of each type of test have been given. Expert judgement is required when determining the appropriate and necessary test to use. These tests do not form part of a routine health examination, and are only used in cases where in the judgement of the Veterinarian, further information is needed to determine the cause of a problem, and the appropriate treatment. WHEN SHOULD AN ANIMAL RECEIVE VETERINARY ATTENTION Veterinary attention may be required should an animal show signs of illness. Any departure from normal health may need to be investigated by a Veterinarian. Of course the experience of an owner may determine whether a condition should be seen. A condition that has been seen before in an animal and known to improve with or without simple treatment, may not 44 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 need veterinary attention, but if the condition persists or does not respond to treatment, then veterinary advice should be sought. Examples of conditions that may not require veterinary attention include : Parasite infestations such as fleas or worms. Mild lameness after a slight accident. A small laceration or graze. If however the signs persist or are associated with any other signs, then attention should be sought. If you are not sure of the health status, then seek advice, even if the matter appears trivial. Veterinary Attention should be sought: If an animal is showing signs of an illness or departure from normal health, of special concern is if it: Appears depressed or disinterested Stops eating and drinking Some conditions require urgent attention and should be treated as an emergency, they include. Unconsciousness Collapse with difficult breathing Severe haemorrhage Severe burns Prolapsed eye Poisoning Snake bite Fractures Severe wounds Difficult urination Difficult birth 45 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 46 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Veterinary Medical Nursing 1 Work Sheet 1 Completing this study sheet will help you to prepare you for Assessment 1. You do not need to submit this worksheet. 1. List signs that may indicate that an animal is in good health ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 2. Provide two definitions of health ___________________________________________________________________________ ___________________________________________________________________________ __________________________________________________________________________ 3. Define physical signs ___________________________________________________________________________ ___________________________________________________________________________ 4. List four signs that may be associated with good health ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 47 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 4. Define what is meant by physiological signs ___________________________________________________________________________ _________________________________________________________________________ 5. List signs that may be associated with normal bodily functions ___________________________________________________________________________ _________________________________________________________________________ 6. Define what is meant by behavioural signs ___________________________________________________________________________ __________________________________________________________________________ 7. List four behavioural signs that may indicate an animal is unwell ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 8. Provide two definitions of disease ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ________________________________________________________________________ 48 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 9. Explain what is meant by the systematic approach to determining if an animal has disease ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 10. List important information that may be assessed in determining an animal’s history ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ __________________________________________________________________________ 11. List 6 observations that may be made when performing as distance examination ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 12. What is meant by the close examination of an animal? ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 13. What is the normal rectal temperature of a dog? _________________________________________________________________________ 49 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 14. List 5 conditions that may cause an animal’s temperature to increase ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ __________________________________________________________________________ 15. Define the term pyrexia _________________________________________________________________________ 16. Outline how you would take an animal’s temperature ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 17. How is the pulse formed? ___________________________________________________________________________ _________________________________________________________________________ 18. List some conditions that may elevate an animal’s pulse rate ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 19. Define tachycardia ___________________________________________________________________________ 50 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 20. Define bradycardia ___________________________________________________________________________ 21. Where is it best to palpate a dog or cat’s pulse? ___________________________________________________________________________ 21. Where is a horse’s pulse normally palpated? ___________________________________________________________________________ 22. What is the name given to listening of internal body sounds? ___________________________________________________________________________ 23. What does the ‘lub dub’ sound represent when listening to the heart? ___________________________________________________________________________ 24. List some normal events that may elevate an animal’s respiratory rate ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 25. List 2 diseases or abnormal conditions that may elevate the respiratory rate of an animal ___________________________________________________________________________ _________________________________________________________________________ 26. Define dyspnoea _________________________________________________________________________ 27. List two conditions that may result in dyspnoea ___________________________________________________________________________ ___________________________________________________________________________ 51 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 28. Outline why mucous membrane colour is assessed and how this is done. ___________________________________________________________________________ ___________________________________________________________________________ _________________________________________________________________________ 29. Why are ancillary tests sometimes required to further assess an animal’s health status ___________________________________________________________________________ __________________________________________________________________________ 31. List 6 conditions that may require urgent veterinary attention (i.e. an emergency) ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 32. You are asked to find one animal to examine. This could be your own pet or a client’s pet if you are working at a vet clinic. Complete a detailed examination of these animals using the form below. Make an entry for each heading, even if it is “normal” that you record. You will require a stethoscope and thermometer to complete this. You need to hand this in to your tutor. (On the following pages) The sheets below are a method of recording factual information about an animal health. There are many different ways of recording this information but the important point is to ensure that it is expressed logically and accurately. 52 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 ANIMAL HEALTH EXAMINATION Student’s name: ______________________________ Animals Name Owners Name ______________________________________ Not required for this report Species ___________________ Breed ___________________ Sex ___________________ Age ___________________ HISTORY For the following record normal, or comment if abnormal giving details. General attitude _____________________________________________________________________ _____________________________________________________________________ Eating ______________________ Drinking _________________ Urination Defaecation _________________ ________________ Tolerance to exercise. _______________________________________________ Recent contact with new animals Travelled away from home _____________________________________ __________________________________________ Is the animal sterilised ______________ Currently Vaccinated ______________ What vaccine ______________ Recent parasite treatment ______________ What treatment______________ Significant past illnesses _____________________________________________________________________ _____________________________________________________________________ Major illnesses of parents _____________________________________________________________________ _____________________________________________________________________ 53 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Current problems _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ How long have these problems been evident ? _____________________________________________________________________ Are they improving , not changing or are they getting worse ? _____________________________________________________________________ Are any other animals affected with this problem ? _____________________________________________________________________ DISTANT EXAMINATION Alertness ________________________________________________ Body condition ________________________________________________ Appearance of skin or coat __________________________________________ Abnormal lumps ________________________________________________ Breathing ________________________________________________ Discharges ________________________________________________ Movement ________________________________________________ Posture ________________________________________________ Behaviour ________________________________________________ Any abnormal signs ________________________________________________ ________________________________________________ 54 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 Close examination Head / neck ________________________________________________ ________________________________________________ Body ________________________________________________ ________________________________________________ Limbs ________________________________________________ ________________________________________________ TPR record values and comment on any abnormalities Temperature ________________________________________________ Pulse ________________________________________________ Respiration ___________________________________________________ Mucous membrane colour ____________________________________________ Capillary Refill Time ____________________________________________ Any other comments __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ Please complete and submit Assessment 1 Now 55 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 1 56 Applied Vocational Training Veterinary Medical Nursing 1 CHAPTER 2 Cause & Transmission of Disease Outline Cause of Disease Infectious Disease Zoonotic Disease Non-infectious Disease Instructions for this chapter Complete all questions and exercises found in this chapter using your notes and information you might research elsewhere. Assessment for this chapter Complete and send in Assessment 2 57 58 Chapter 2 Chapter Two Outline Causes of Disease Congenital Inherited Non-inherited Acquired Infectious Diseases Bacteria Viruses Protozoa Fungi Internal Parasites Trematodes Cestodes Nematodes External Parasites Fleas Ticks Lice Mites Zoonotic Disease Non-infectious Diseases Nutritional Diseases Hormonal Diseases Degenerative Diseases Metabolic Diseases Inherited Diseases Physical Diseases & Trauma Chemical Diseases Immunological Diseases Psychological Diseases Unknown causes 59 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 60 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 CAUSES OF DISEASES Disease can have many causes. Often a disease will not be caused by one factor, but by a combination of factors. For instance an animal that has poor nutrition that has been kept in inadequate housing, is more likely to suffer from disease, than one kept in better conditions. This section attempts to categorise diseases according to their cause. This is a useful approach for gaining a better understanding of animal health. A simple classification of disease can be whether a disease is present in an individual at birth, or whether it affects an animal after birth and during its life. Diseases that are present when an animal is born are described as congenital. Diseases that animal get later on, after birth or throughout its life are described as acquired diseases. Congenital DISEASE Acquired 61 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 CONGENITAL DISEASES These are diseases that can be seen at birth. An animal gets the disease whilst still in the uterus of the mother during pregnancy. Some examples include: * infection with parasites * abnormal body shape ( e.g. two heads, cleft palate ) * deafness * blood disorders There are many more examples of congenital diseases. Of course, many diseases that are seen at birth can also be acquired by animals later in life ( e.g. parasite infections ). Kitten foetus in the uterus Some congenital diseases are fatal, which means causing the death of the animal (such as having two heads) whilst others may not have a serious effect on the animal’s health. Congenital diseases can further be classified according to whether they are passed on from the parents in their genetic make up, or caused by other factors. These can be described as inherited or non inherited diseases. 62 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Inherited diseases Are those which are passed on from one or both of the parents in the genetic information (chromosomes in the egg and sperm) given to the offspring. Some examples include: * cryptorchidism ( absence of one or more testes ) * hip dysplasia in dogs * some blood disorders Non inherited diseases Are those which occur during pregnancy, but are not passed on from the parents. Infections, the effects of drugs, and trauma to the mother are a few possible causes. Some examples include: * rickets due to a vitamin deficiency. * parasite infections * blood incompatibility DISEASE Congenital Inherited Acquired Non-inherited 63 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 ACQUIRED DISEASES All the other diseases that affect an animal shortly after birth and throughout its life, can be considered as acquired diseases. Of course there are thousands of diseases that fit this category, including: * distemper in dogs * rabies in horses * sunburn * snake bite * trauma Study Exercise Consider some diseases or conditions that you know affect animals (or humans). Write down ten of these below and consider whether they are either congenital or acquired. Disease Classification __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ __________________ ____________________ 64 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 A further classification of acquired diseases includes describing these diseases as either infectious or non infectious. INFECTIOUS DISEASES Are those caused by living organisms that enter and adversely affect the animal. A bacterial disease such as tetanus is a good example. NON INFECTIOUS DISEASES Are those caused by other factors , such as sunburn, trauma or dietary problems. DISEASE Congenital Inherited Non inherited Acquired Infectious Non-infectious 65 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 INFECTIOUS DISEASES These diseases are caused by living organisms entering the animal’s body and adversely affecting the health of the animal. However there are several important considerations about these types of diseases: Many organisms live quite harmoniously on or within animals, without causing any disease at all. Most animals (and humans) have populations of bacteria on the skin and within the intestine that protect the skin, and aid in digestion. In fact, in some cases these organisms are essential for the life of the animal. A good example here is the billions of bacteria and protozoans that live in the stomach and intestines of animals that are vegetarian, such as the horse and cow. These organisms digest the plant material, providing essential nutrients for the host. Without these organisms, the animal would not be able to live. Organisms that are capable of causing disease are described as pathogenic, to set them aside from the other numerous organisms that are harmless to animals and man. These diseases or organisms can be acquired from either the environment of the animal, such as the ground, or directly from other animals. Infectious diseases that can be spread directly from animal to animal are described as contagious. Feline respiratory disease, canine parvovirus, and the human flu are all examples of contagious diseases. Cat with ocular and nasal discharge typical of ‘cat flu’ 66 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Stress will have an impact on the animal’s ability to resist disease. An animal that is stressed, is more likely to suffer from an infectious disease, or in fact, disease in general. In some instances, usually harmless organisms living in or on an animal may cause disease if the animal is stressed. Some important factors that might stress an animal include: * poor nutrition * poor housing * overcrowding * the presence of other diseases IMPORTANT INFECTIOUS DISEASES Infectious diseases are usually classified further according to the type of organism that causes the disease. The more common causes are shown below. Bacteria Viruses Infectious causes of disease Fungi Protozoans Parasites Some other classes of organisms such as Rickettsia ( tiny disease forming organisms ) exist, but are less frequently seen. 67 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 BACTERIA Bacteria are tiny organisms that can only be seen under the light microscope. Usually they need to be magnified at least 400 times to be visible. (Approximately 0.5-5um (micrometre) in diameter). There are numerous different types of bacteria. They are found everywhere in nature, on land and in water. In most instances they are useful in breaking down dead organic matter (such as plants and animals). They are used by some animals to assist breaking down vegetable matter in their bowel, and humans use them to manufacture foods such as wine and cheese. Pathogenic bacteria are those that can cause disease. Some examples of diseases caused by bacteria include: Tetanus A disease affecting most domestic animals. It affects the nervous system causing convulsions and sometimes death. The bacteria is acquired from soil and is not contagious (passed from animal to animal) Abscesses Especially in cats after fights. The bacteria are introduced under the skin, and an accumulation of pus occurs. Vomiting and diarrhoea Many bacteria can damage the lining of the stomach and intestine. All species of animals can be affected. Bacteria such as salmonella may be involved. Of course many other causes can be found for vomiting and diarrhoea, including viruses, poisons and even poor diets. 68 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 VIRUSES Viruses are much smaller than bacteria and can only be seen using an electron microscope that magnifies in the order of 400,000 times. (Approximately 20-300 nanometres in diameter) They have a unique structure that often resembles a crystalline shape than that of a living thing. Viruses live and reproduce only in the cells of plants and animals. Not all viruses are harmful, but many pathogenic ones are capable of causing contagious diseases (spread from animal to animal). Some examples of diseases caused by viruses include: Distemper A disease affecting the dog that can result in the death of the animal from convulsions. Feline Respiratory Disease Better known as cat flu. A highly contagious and sometimes serious disease of cats. Foot and mouth disease A debilitating disease of livestock that can have a dramatic effect on production of stock and a country’s economic situation ( you are unable to sell affected stock ) Human diseases Colds, measles, chicken pox, AID’s are all examples of human viral diseases. 69 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 PROTOZOA Protozoans are single celled organisms that may be seen with the light microscope and magnification as little as 50 times. (most are between 10-50 micrometres in diameter). Magnified view of a protozoa with cilia (tiny hair-like structures which beat enabling the microbe to be mobile) There are thousands of different species of protozoa found naturally in the environment on both land and in water. They have a useful role in the environment, being an important part of the ecosystem. In plant eating animals such as cattle and horses they form an important part of the microbial flora of the stomach and intestine that digest plant material. However, occasionally these organisms can cause disease, especially if the host animal is stressed or has an immune system that is not working properly. Some examples of diseases caused by protozoans include: Coccidiosis A disease causing severe enteritis (diarrhoea features) in animals, often blood stained and resulting in death. Toxoplasmosis A mild disease of cats, which may cause diarrhoea, but may also go unnoticed, with cats carrying the disease. It is of concern as it may cause abortion in women, if contracted from cats. 70 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Giardia infection A common parasite of the intestine that can cause diarrhoea in animals and man. Giardia: an intestinal protozoa, common in many animals FUNGI Fungi are plant like organisms that are found widely in nature. Mushrooms are a large form of fungi. Smaller ones can be seen under the microscope with low magnification, and have a much simpler structure. They are useful in many instances, including the production of antibiotics ( penicillin was first produced by a fungus ) and yeast, another fungus, is well known for the production of food and beverages ( especially by beer drinkers !) However a few fungi may cause disease in animals. Malassezia, a yeast (single celled fungus) 71 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Some examples of diseases caused by fungi include : Ringworm Not a worm at all, but actually a fungus that may cause skin irritation and hair loss in animals and man. It can be acquired from other animals and can even be found in the soil. Ear infections Often fungi are found in association with bacteria and other organisms in ears of animals that are badly infected. PARASITES Parasites may be considered as living organisms (plant or animal) that live on or within another organism at some expense to the host. In this case we are interested in organisms that live on or within animals, causing some harm to them. There are thousands of parasites that have been observed, some causing only minor problems to the host, others causing severe disease and death. These parasites are also very diverse. A convenient way of looking at them is to consider them as either internal parasites or external parasites. Internal Parasites These are the organisms that live inside the animal, and of most concern to animal health are the helminths (or worms). They often are found in the stomach and intestine, but may also be found in the blood, body organs and skin. These range from a few mm in length to metres in length. Some other parasites such as the larvae of certain insects will also live inside the body. The bot fly in horses is one such example, where the fly larvae live in the stomach. 72 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 External Parasites These are the organisms that live on the outside of the animal, in the skin and hair. Predominantly these are insects of one kind or another, the common flea being a well known example. Internal PARASITES External 73 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 INTERNAL PARASITES Important types of worms that affect animals are: * Trematodes ( flukes ) * Cestodes ( tapeworms ) * Nematodes ( roundworms ) Trematodes These are flat, leaf like worms that may have adults that are several centimetres in size. They may affect the liver, lungs and blood of animals. Often they have a life cycle that involves another host other than the final host. This is called an intermediate host. In cattle, a liver fluke that causes significant damage has an intermediate host in a particular snail. That is, once the adult flukes produce eggs, the immature flukes must develop in the snail, before affecting cattle again. The fluke is only found in areas where the snails occur. Cestodes Cestodes are the tapeworms. They affect all domestic animals and appear as flat ribbon like worms. They may be as small as a grain of rice, or as large as several metres. The body of tapeworms is segmented, and all tapeworms have an indirect life cycle. A tapeworm, notice the individual segments, each containing hundreds of eggs 74 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 This means that once the adult worm lays eggs, these eggs must develop through one or more intermediate hosts. Usually the adult tapeworms will live in the intestine of its host, often causing little damage However the developing larvae of the tapeworm may cause severe damage to the intermediate host. The hydatid tapeworm of dogs is one where the adult worms live in the dog intestine causing little damage. Eggs are passed out in the faeces of dogs, contaminating pasture. These are then ingested ( eaten ) by sheep or other grazing animals, and cysts form in the internal organs, these animals ( sheep ) are the intermediate hosts. Often these cysts cause severe damage, and may even result in death. The worm will only pass back to the dog when the dog eats one of these cysts in the intermediate host. (In Australia the main problem is with dogs being fed sheep offal) Dogs cannot be infected by eating the eggs directly. The parasite must first develop in the intermediate host before it can affect the adult dog again. A serious side to this disease occurs when children (or occasionally adults) accidentally eat the eggs and end up with cysts in abdomen or lungs, often causing severe disease. Nematodes These are the roundworms. They affect all species of domestic animals, and can vary in size from a few millimetres up to many centimetres. They are basically cylindrical in shape, a large one resembling a piece of spaghetti. Roundworms in the intestine of a bird. Image: the ranger 75 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Adult worms usually live in the intestines, but occasionally are found elsewhere in the body. Heartworm in dogs is one example, where the adult worms live in the heart. The life cycle of nematodes may be: * Direct with the adult worms laying eggs, which are then consumed by the next animal which then becomes affected. * Indirect with an intermediate host involved. ( in the case of heartworm in dogs, the larvae must pass through a mosquito before being able to reinfect a dog ) Mosquito. Intermediate host of canine heartworm The adults themselves may cause little damage or severe damage, depending on the worm. Often in livestock, heavy infestations with parasites will cause diarrhoea and poor condition. It may be the larvae ( the immature worm that hatches from the egg ) that causes damage. Often the larvae before reaching an adult stage in the intestine, will travel around the body as part of its development, sometimes causing damage to internal organs such as the liver, blood vessels, and even the eye. The larvae of the red worm in horses is one example where the adult lives harmlessly in the intestine, but the developing stage of the worm may cause severe damage to an artery supplying the intestine with blood, that in severe cases, the animal may die from colic 76 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 EXTERNAL PARASITES Important types of external parasites that affect animals are: * Fleas * Ticks * Lice * Mites Fleas Fleas affect many species including dogs, cats and rabbits. They usually breed in the environment, off the animal, and may lay dormant in the environment for many months. They can be seen as small creatures with the unaided eye. They cause problems for the host in several ways: * skin irritation due to biting and feeding off host * loss of blood in severe infestations * cause allergies in some animals, resulting in excessive scratching * can transmit other parasites such as tapeworms * can transmit diseases ( such as myxomatosis in rabbits ) 77 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Ticks Ticks are blood sucking creatures that affect most domestic animals. They often live off the host, moving onto the host to feed on its blood. They can be quite large ( up to 5 mm ) and are easily seen with the naked eye. Often they will have an engorged abdomen that is full of the host’s blood. A tick. Image tick texas They cause disease in several ways: * skin irritation due to feeding off host * loss of blood in severe infestations * transmit other diseases * some species of ticks can produce toxins that can cause paralysis Lice Lice are small insects that usually feed on skin debris on the skin of animals. They are usually quite small, but can be seen by careful observation, with the naked eye. Other than causing irritation they do not usually cause severe disease. Their life cycle can be spent entirely on the host, or some time may be spent off the host. 78 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Mites Are small creatures (related to spiders) that live on and in the skin of animals. They are tiny and cannot be seen with the naked eye, but can be seen under the microscope with low magnification. They can be present burrowing in the skin and cause little problem in some animals, whilst other animals lose hair and find them most irritating. Scabies is a disease caused by a mite that usually causes severe itching in dogs and foxes. It can also affect humans. In summary : PARASITES Internal External Trematodes Fleas Cestodes Ticks Nematodes Lice Mites 79 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 ZOONOSES Zoonoses is a term used to describe diseases that can be transferred from animal to man or from man to animal. Some diseases that are zoonotic (causing a zoonoses) have already been considered including: * ringworm * toxoplasmosis * hydatid disease * scabies Some other important diseases that can be transmitted from animals to man include : * rabies ( a virus ) * anthrax ( a bacteria ) * roundworm larvae 80 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 NON-INFECTIOUS DISEASES This broad category of disease describes all those other diseases that are not caused by infectious organisms. That is, they are not caused by bacteria or viruses or any other living creature, but by other causes. This is a very large and varied group of diseases and it is useful to further classify these into more specific groups. One such classification is shown below: * Nutritional diseases * Physical diseases or trauma * Hormonal diseases * Chemical diseases * Degenerative diseases * Immunological diseases * Metabolic diseases * Psychological diseases * Inherited diseases * Unknown causes 81 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Nutritional diseases These are caused by an excess or deficiency of components of the diet. Rickets is a disease that may be seen with dietary deficiencies of calcium or Vitamin D resulting in misshapen and weak bones. Obesity is another example that may be caused by excessive food intake. There are hundreds of diseases that have been identified and fit into this category. Hormonal diseases These diseases are associated with an excess or deficiency of a particular hormone. Hormones are chemical messengers in the body, and abnormal levels of hormones cause abnormal body function. Diabetes mellitus is a disease that features excessive drinking and urinating, weight loss and other body changes. It is caused by a deficiency of the hormone insulin. Dozens of other hormonal diseases have been identified. Degenerative diseases These diseases are associated with a breakdown or wearing of tissues. Age or excessive use often contribute to these diseases. Arthritis is an example where the animal’s joints become worn and painful. There are many examples of degenerative diseases seen in animals Metabolic diseases Are diseases caused by a change in the normal internal environment of the animal. 82 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Acidosis is a condition that describes an increase acidity of the blood, and may follow excessive exercise. Inherited diseases Diseases that are passed on from parent to offspring. Hip dysplasia in dogs, umbilical hernia in horses are two examples. There are hundreds of examples in animals of this type of disease. It is important to note that genetic diseases can be passed down from parents who are not showing any signs of the disease, but are carrying information for a condition in their genetic make up. Physical diseases or trauma These diseases are caused by physical agents. Trauma is commonly seen in animals that have been fighting, or have met with a car on the road. Burns, radiation exposure (such as sunburn ), fractures and hypothermia ( excessive exposure to cold ) are all examples. Chemical diseases Diseases associated with chemical agents. Most poisoning’s seen in animals fall into this category Snail and rat baits will often poison pets when accidentally eaten. There are many toxic plants that will affect livestock. Some animals such as spiders and snakes can poison animals as well. Immunological diseases The immune system is responsible for the animal’s response to disease. Abnormalities are seen where a lack of response to a disease occurs such as in immuno deficiency disease, or where an excessive response occurs such as with allergic conditions 83 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Psychological diseases Many diseases seen in animals have a basis in abnormal behaviour. Tail chasing in dogs, wind sucking in horses or even excessive aggression fall into this category. Unknown causes Many diseases occur that have an unknown cause. Examples here include some of the cancerous diseases. It is important to note that this classification is not complete, but does classify most diseases. Many diseases may have causes from several categories. For example, obesity (excessive fat) may be caused by nutritional problems, but in some animals it can be caused by a hormonal condition called hypothyroidism, where too little of the thyroid hormone is found in the body. It is thought that obesity may also be inherited from ones parents. Arthritis (inflammation of a joint) can be caused by trauma, degeneration, infection and even through an abnormal immune response. It can be seen that with the above two examples, a single type of disease can be caused in several different ways. 84 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 HOW INFECTIOUS DISEASES ENTER THE BODY For an infectious disease to be passed between one animal and another, it must first leave one host and then enter another. The passage of a disease from one animal to another is called the transmission of the disease, or how the disease is transmitted. An infectious disease can leave the host in many normal body products, such as faeces or in respiratory droplets in the breath. Additionally, disease can leave an animal in more unusual ways such as in vomit or blood. The diagram below illustrates several ways a disease may leave a host ears faeces eyes respiratory droplets saliva vaginal fluids milk hair and skin urine 85 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Respiratory droplets are a common way for airborne infections such as respiratory viruses to be passed from animal to animal. Sneezing, coughing and just breathing will produce fine droplets of water that may contain micro-organisms. Some other means of an infection leaving a host include: * Teeth and nails ( during play or a fight ) * Blood * Vomit * Wounds or sores * During pregnancy across the uterus * Semen, vaginal discharges * Saliva * Skin and hair HOW DISEASES MIGHT ENTER A NEW HOST The same pathways that are used for a disease to leave a host, may be used for a disease to enter another animal. Any opening in that animal may allow organisms to enter the inside, such as the: * nose * mouth * anus * vagina * penis Some organisms can enter the animal in other ways, some examples include: * passing onto or through the skin * entering the ears and / or eyes * passing through the placenta of a pregnant mother to the foetus 86 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 TRANSMISSION OF DISEASES Having discussed how a disease might leave and enter an animal, we now need to consider how the disease is passed or transmitted from one animal to another. Diseases may be transmitted either directly or indirectly. DIRECT DISEASE TRANSMISSION INDIRECT DIRECT TRANSMISSION Here the animals have direct contact and the disease causing organisms will be transferred from one animal to the next. Some actions that will permit direct transmission include: * touching * sucking * licking * biting * breathing , sneezing and coughing * sexual contact 87 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 INDIRECT TRANSMISSION In the case of indirect transmission, the disease is not passed directly from one animal to another, but instead is passed onto some other object or material with which the next animal then comes in contact with. Disease leaves Infected animal Disease enters new animal Object There are numerous examples of objects or materials that can diseases can be transmitted indirectly. Some examples are: * soil * water * brushes * blankets * food * mosquitoes * flies * peoples hands * injections * car tyres 88 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Study Exercise Consider some other means of a disease being transmitted indirectly. Make a note of a few in the space below. _____________________________________________________________________ ____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 89 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Some specific terms are used to describe different agents that transmit diseases indirectly. Fomites are objects which are inanimate or not alive, that can transmit a disease. Some examples include brushes, food bowls, gloves, cars tyres, injections. Food bowl can act as a fomite. Image waywildpets Intermediate hosts are living creatures that transmit an infectious micro-organism, where the disease must pass through the creature before being passed on to the next animal. Usually the organism causing the disease will not be able to infect another animal unless it spends some time in that intermediate host. (it usually matures there) A tapeworm that lives in dogs, Dipylidium caninum, is a good example here. The tapeworm eggs are passed in the faeces, the immature tapeworm (larva) must then develop in the flea, before it can reinfect the dog. The eggs cannot pass the disease on to another dog unless it first passes through the flea. The flea is called the intermediate host for this disease. Of course disease can be spread by flies, rats, cockroaches and many other animal pests, but this will usually be on the surface of the animal, and the disease does not have to be carried by the particular animal, it could just as easily be carried on a glove or other fomite. 90 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 In summary, an animal may be infected from several sources, depending on the particular disease. Consideration should be given to the following when looking for the source of an infection: * Animal’s environment * Animals in the same establishment * Newly acquired animals * People entering an establishment * Food and water * Bedding and other fomites * Air * Vermin Some terms associated with examining a disease problem Endemic This describes the presence of a disease at low levels within a population. For instance, if a cattery has occasional cases of feline respiratory disease (cat flu); we can describe this as endemic. Human flu is usually endemic in humans; there is always someone with it! Epidemic When the disease affects a large number of individuals at the same time. Often the above two examples (cat flu and flu) may affects a lot of animals or humans, there is an outbreak, and this is described as an epidemic. For instance if 50 % of the cats in the cattery were affected, this would be considered an epidemic. Each winter a flu epidemic affects humans, almost everyone you know seems to get a bout of flu around the same time of year! Acute disease Is a disease that comes on suddenly, often with obvious signs of illness. Chronic disease Is a disease that has a long duration, often being less severe than an acute disease. 91 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Carrier Is the term used to describe an animal that is carrying an infectious disease. In other words, this animal can be a source of infection for other animals. In some cases the animal may have recovered from the disease and now show no signs of illness, but still be carrying the disease organisms and capable of spreading the disease. These animals pose a particular problem in controlling the spread of disease. Different diseases will leave and enter the host differently. For instance, a disease that is passed via respiratory droplets will not enter the host through the skin. Some diseases may only be transmitted by direct contact, which suggests that the organisms cannot live off the host (the original animal) for any period of time. However some diseases can lie dormant or survive in the environment for months or longer. A sound knowledge of a particular disease will provide valuable information on the steps needed to prevent that particular disease. 92 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Vet Medical Nursing 1 Work Sheet 2 Completing this study sheet will help you to prepare you for Assessment 2. You do not need to submit this worksheet. 1. Define the following terms Congenital disease _____________________________________________________________________ Acquired disease _____________________________________________________________________ 2. 3. List four examples of congenital diseases ___________________________ _____________________________ ___________________________ _____________________________ Explain the meaning of a fatal disease _________________________________________________________________________ 4 Explain the difference between an inherited and non inherited disease. ___________________________________________________________________________ _________________________________________________________________________ 5. Are all congenital diseases inherited? _________________________________________________________________________ 6. 7. List four examples of acquired diseases in animals ___________________________ _____________________________ ___________________________ _____________________________ Define an infectious disease _________________________________________________________________________ ______________________________________________________________________ 93 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 8. Discuss an example where the presence of micro organisms in or on an animal may be beneficial to that animal. ________________________________________________________________________ __________________________________________________________________________ 9. Explain the meaning of a pathogenic organism ________________________________________________________________________ ________________________________________________________________________ 10. Name 4 factors that might cause an animal to be stressed and more prone to disease 11. __________________________ ___________________________ __________________________ ___________________________ List the 5 main groups of organisms that may cause an infectious disease. __________________________ ___________________________ __________________________ ___________________________ __________________________ 94 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 12. Complete the following table. For the parasites, choose one type only (e.g. fleas) ORGANISM Size Useful role Example of disease Bacteria Virus Protozoan Fungi Internal Parasite External Parasite 13. Define zoonosis and give two examples of diseases that are zoonotic ___________________________________________________________________________ _________________________________________________________________________ ___________________________________________________________________________ 95 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 14. Complete the following table Type of Disease Explain cause of disease One example Nutritional diseases Hormonal diseases Degenerative diseases Metabolic diseases Inherited diseases Physical diseases or trauma Chemical diseases Immunological diseases Psychological diseases Unknown causes 15. Consider the situation where an outbreak of a contagious respiratory disease occurs in a cattery. The signs of illness include sneezing, coughing and fever. You know that this particular disease is a highly contagious virus, that can be transmitted directly, and survive outside of the host on inanimate objects or other materials for up to 24 hours. This disease has spread to another cattery 1 km away, and it is fairly certain that the first cattery is the source of the infection. 96 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Suggest some possible ways that the disease could have passed from the first cattery to the second one, the following headings should give some guidelines. Try to describe at least two possible ways for each category. Use the back of the paper if you need more space. People Animals Fomites Insects Other ways 97 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 2 Please complete and submit Assessment 2 Now 98 Applied Vocational Training Veterinary Medical Nursing 1 CHAPTER 3 Diagnosis of Disease/Body’s Response to Disease Outline Diagnosis of Disease Determining the Cause of Disease The Disease Response to Disease Prevention of Entry into Body Defence to Disease Instructions for this chapter Complete all questions and exercises found in this chapter using your notes and information you might research elsewhere. Assessment for this chapter Complete and send in Assessment 3 99 100 Chapter 3 Chapter Three Outline Diagnosis of Disease Determining the Cause of Disease Systematic approach The Diagnosis The Disease Response to infectious disease Prevention of entry to the body Skin Mucous membranes Defences mechanisms on the body’s surface Defences within the body Non-specific defences Inflammation Lymphatic system Spleen Specific responses Production of antibodies Memory Cell-mediated response Outcomes of Disease Resolution Chronic condition Death 101 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Prognosis 102 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 DIAGNOSIS OF DISEASE Diagnosis means determining the actual cause of a disease. This is important for determining the best means of control and treatment of a particular disease. Looking at a particular example may help explain this concept. Consider a rabbit with skin irritation. It may be rubbing its skin, losing hair and feel quite unwell, not eating properly and not keeping its normal weight. How do we go about treating this animal? The first step is to establish a diagnosis. In other words find out the cause. In this instance there could be many possibilities. A few are: Fleas Mites Allergic condition Sunburn Contact with material that causes irritation 103 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Clearly it is important to determine the actual cause of the disease, as the treatment for each different cause varies greatly. If fleas are the problem, then insecticides will be used for treatment. But if the problem is with sunburn, then treating fleas will have no effect at all. The animal in this case will need to be brought out of the sun. Consider the case of a horse with a runny nose. Again there are many possible causes of this problem. They include Viral infection Bacterial infection ( such as strangles ) Something is stuck in the nose ( such as a grass seed ) A tumour Allergy Once again, determining the cause or making a diagnosis is critical to determine the correct treatment of the animal. If a bacterial infection is present then antibiotics will be useful in the treatment. However if a grass seed is in the nostril, antibiotics will have no effect, and the seed will need to be removed. DETERMINING THE CAUSE OF A DISEASE The cause of a disease is determined by using the same approach as used for the health examination previously discussed. Exactly the same approach is used, in a systematic manner, carefully recording the history and physical signs SYSTEMATIC APPROACH History Distant examination Close examination Ancillary tests 104 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Once all the information is carefully recorded, the person conducting the examination will make a diagnosis (determine the likely cause) of the disease, which will determine the action to be taken. There are some special considerations that apply to making a diagnosis. SYSTEMATIC EXAMINATION The full history and examination will generally always be performed on a sick animal. Even if the clinician (veterinarian) has an idea of the most likely cause, the first step is to carefully find out what condition the animal is in. Such practices as TPR (temperature, pulse and respiration) are fundamental to a sound diagnostic approach. There may be occasions where in an emergency, treatment is initiated immediately without a full examination. But even in emergency case, determining the temperature, pulse and monitoring other signs will allow the extent of the recovery to be monitored. The history is often critical in making a diagnosis. Consider a female dog that is having convulsions. Some possible causes include snake bite, poisoning or even a brain disorder. However if the bitch has had pups recently, it is more likely that the convulsions are caused by low blood calcium (milk fever) associated with lactation. A full examination is needed in each case to accurately determine the cause of the disease. Often the diagnosis will be made based on the history and the physical examination only. In the above instance, the history of recent birth along with the signs of convulsions, and no evidence of another disease being the cause, may be sufficient evidence to initiate treatment for milk fever ( which involves injecting a solution of calcium into a vein ). In cases where the diagnosis is not clear or the animal fails to respond to treatment, ancillary tests as described before may be used. Often these tests can be expensive, and the wise choice of which tests to use is necessary. 105 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 THE DIAGNOSIS Despite a full history and examination, plus appropriate ancillary tests, it may still not be possible to make a diagnosis and determine the cause of the disease. Some diseases are difficult to detect, even with rigorous examination. Diseases of the nervous system can often be a particular challenge. One example is a horse that is having seizures (fits). Despite a full examination and extensive testing it may not be clear as to the cause. It is not really practical to take radiographs of a horse’s brain. Many viruses are very difficult to find in the laboratory, and also the testing can be particularly expensive. In some cases surgery may be used to attempt to determine the cause of the disease and as a means of collecting specimens for further examination. An example might be a puppy that has a blockage of the bowel and is vomiting and not passing faeces. If other diagnostic tests such as radiographs do not reveal the cause, it may be appropriate to perform a laparotomy (incision into the abdomen) and physically examine the bowel and associated structures. Should a physical obstruction be found (such as part of a slipper) it may be removed at this time. Often conducting a post mortem examination of animals that have recently died is particularly useful, but will not always reveal the cause of disease. With animals that are farmed ( such as sheep ) , a very sick animal will be euthanased ( killed humanely ) and a post mortem examination performed in an attempt to determine the cause of disease. This will permit other animals showing the same signs to be treated. 106 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 THE DISEASE It is true that common diseases occur commonly. For example, a dog that has recently been boarded at a kennel and now has a cough is likely to have kennel cough. However this does not mean that it must have kennel cough. It is possible that it has some other disease that causes coughing such as congestive heart failure. In the case discussed above with the bitch with milk fever, it is possible that the animal was bitten by a snake and that that the history of recent birth is not relevant. Of course it is more likely that milk fever is the cause, but other causes cannot be ruled out. Generally no disease will have signs that indicate one specific diagnosis A proper examination is essential in all cases. 107 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 RESPONSE TO INFECTIOUS DISEASE The environment that an animal lives in is full of potentially infectious micro -organisms. The air, ground, food and water may all contain organisms that are potentially harmful. Usually an animal will constantly come in contact with other animals that may also be harbouring potentially harmful organisms. Of course, most animals enjoy a healthy existence for most of the time. This occurs because an animal has defences against these organisms that might cause disease. An animal will only succumb to an infectious disease if these defences do not function properly, or if the organisms causing the disease overwhelm the animal’s defences. These defences of an animal are referred to as immunity (the ability to resist). The defences of an animal occur on both the outside and inside of the body. They function to prevent micro-organisms from entering the body, and act to kill or inactivate organisms should they enter. Prevents organisms entering the body Animal’s Defence Kills or inactivates organisms that enter the body PREVENTING ENTRY INTO THE BODY Several barriers and mechanisms exist in animals to prevent the entry of micro -organisms into the body. These mechanisms are sometimes referred to as innate immunity, innate meaning that an animal is born with these. 108 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 These processes occur on the skin and the mucous membranes (the lining membranes of body cavities such as the mouth, the nose and trachea). Skin Barriers Mucous Membranes SKIN The skin of an animal is exposed to the environment and other animals, and may often be in contact with potentially disease causing organisms. The skin acts in several ways to prevent micro - organisms entering the body, they include: Physical Barrier If the skin remains unbroken, the tough outer layer (the epidermis) acts as a physical barrier preventing the entry of micro-organisms. For an infectious organism to enter through the skin, the skin must be damaged as might happen with a cut or graze, or be punctured as might occur in a fight or by insect bites. Production of chemicals Various areas of skin produce sweat, oils and wax. Most of these chemicals are harmful to many micro-organisms. Useful micro – organisms Populations of bacteria live on the skin of animals without causing any harm. These are referred to as normal flora. They live on the skin and are unaffected by the normal defences of animal. Their presence will discourage the action of foreign, potentially disease causing bacteria as they physically take up space where other organisms might try to invade and they will produce chemicals that are toxic to (kill) other bacteria. 109 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 MUCOUS MEMBRANES These are the linings of the body cavities such as the respiratory tract and the gastro intestinal tract. The lining surface of the mouth and eye (conjunctiva) are good examples of mucous membranes. Infectious micro - organisms may also come into contact with these membranes, and there are several mechanisms which prevent the entry of these micro-organisms into the body. Physical barriers As described with the skin, the mucous membranes are fairly tough and prevent organisms from easily entering the body. They must be damaged or overwhelmed (with a severe infection) for organisms to pass through them. Mucous membranes produce liquid (mucus) that will physically wash and flush away microorganisms. Hairs or hair-like structures line the respiratory tract, right the way down to the lungs. In combination with mucus (the liquid produced) hairs will trap microorganisms. The large hairs of the nose form a good Cilia Air passage barrier, and further down the tract in the trachea and bronchi, hair-like projections from the lining epithelium are tiny and can only be seen with the microscope. These tiny structures are called cilia and they all beat in a rhythmic way to transport debris (such as dust) and trapped organisms back up to the pharynx (in the throat) where they can be expelled or Cilia beat upwards towards mouth swallowed. The flushing action of liquids is important as a defence mechanism. Tears, saliva, bile (from the liver), urine and the moist digested food all act to flush organisms away and prevent them lodging on surfaces. 110 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Vomiting, sneezing and coughing are processes that will also assist in physically ejecting disease causing organisms from the body. Production of chemicals Various chemicals are produced that have an anti-microbial action (they kill or inactivate micro-organisms) and include: tears saliva mucus gastric acid vaginal secretions urine Useful micro organisms As described for the skin, populations of harmless bacteria may be found in the upper respiratory tract, the gastro intestinal tract and the vagina; these bacteria have a protective role. 111 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Defence Barriers on body surfaces EYES Tears wash / anti- microbial SKIN Tough / waterproof / anti-microbial MOUTH Saliva wash / anti- microbial BLADDER Urine wash / anti- microbial VAGINA anti- microbial STOMACH Acid anti-microbial AIRWAYS Mucus / hair wash / anti- microbial As can be seen, these defences are significant, and protect the animal from the day to day infectious organisms that it might encounter. However, there are many occasions in an animal’s life where invading organisms will be able to pass these initial defences and actually enter the animal’s body. Perhaps there is physical injury to the animal, or the organism is able to pass through these defence mechanisms (the flu virus in humans is a good example of an organism that can bypass the body’s initial defences). Should an organism pass into the body then a new line of defence is mounted in an attempt to prevent the organism overwhelming the animal. 112 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 DEFENCES WITHIN THE BODY Two different processes are seen within the body should an organism enter. They are described as being non - specific or specific. Non-specific responses occur when any foreign organism enters the body. It doesn’t matter what the organism is, the responses will occur. In other words, the same process will occur without any recognition by the body of the invading organism. Specific response occurs when the body recognises a particular organism and mounts a defence targeted at that particular organism. Specific Defence in the Body Non - Specific 113 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 NON - SPECIFIC RESPONSES Three important processes are involved. 1. inflammation 2. the lymphatic system 3. the spleen These processes will be the same for any organism, a virus, a bacteria or even a worm. No recognition of the invading organism occurs, only the fact that it is foreign and should not be in the body. These processes are aimed at destroying and eliminating the organisms from the body. INFLAMMATION Most people are aware of the signs of inflammation. Think of a splinter in your hand or a hard knock to your leg. Inflammation is the body’s first line of response to an injury, whether it is caused by an invading organism or any other cause (such as sunburn, or trauma, or even a mosquito bite) The signs of inflammation are that the affected area becomes: red hot swollen painful with some loss of function 114 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Damage to the cells of the body causes a release of chemicals into the surrounding tissues that cause the inflammation to occur. The most important of these chemicals is called histamine. Histamine affects the blood vessels in the area in several ways. They dilate (relax and become bigger) allowing more blood into the damaged area (this causes the redness and heat) The vessel walls become permeable (allowing materials to pass through them). As a result of these changes to blood vessels: Proteins involved in defence and repair leave the blood vessels White blood cells leave the blood vessels and destroy foreign materials by engulfing (taking within them) them. One cell might be able to destroy up to 100 bacteria. The name of the white blood cells that act early in the inflammatory response are neutrophils. Later in the response a different cell called a monocyte becomes involved. When describing inflammation of a particular area in the body, the suffix - itis is used. For instance if inflammation of the stomach occurs, it is described as gastritis. This comes from gastric: referring to stomach -itis: inflammation of Dermatitis: inflammation of the skin. Very mild inflammation on the tip of the nose as evidence by reddening. A few examples of terminology are: dermatitis inflammation of the skin enteritis inflammation of the intestine conjunctivitis inflammation of the conjunctiva ( around eyes ) cystitis inflammation of the bladder 115 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 It is most important to realise that inflammation will be caused by any damage to the affected area. Inflammation will be caused by invading micro - organisms, but there can be many other causes of inflammation, such as trauma, chemical damage, heat and many other agents such as poisons. In the case of gastritis above, it is common to see gastritis as a result of an infection with bacteria or a virus. However gastritis could be caused by an animal eating something that is acid or caustic. Even a tumour could damage the stomach causing gastritis. So the terminology relating to inflammation does not tell the cause of the disease, it indicates only that the affected organ is inflamed. THE LYMPHATIC SYSTEM Should an organism get past the initial defences in the body, and the white cells that act in the inflammatory process not be able to contain the infection, other defence mechanisms come into play. Surrounding all cells is fluid, and this fluid circulates via a network of vessels called lymphatic vessels. This network is similar to the blood circulation, except that the vessels are thin walled, and only carry fluid, not blood. This system forms a type of drainage, with fluid being collected from around the cells, and sent back towards the heart. However, along the way there are many small structures called lymph nodes which act as filters to trap and destroy any foreign materials found in the tissue fluids. These lymph nodes may be as small as a few millimetres or in large animals as big as a golf ball. They exist right throughout the animal. We are all familiar with the “glands” that may become swollen around our own throat when we have the flu or a sore throat. These are the lymph nodes that protect the mouth and throat area. Various regions of the body have nodes that protect that area. For instance, looking at an animal’s leg: 116 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 The arrows indicate the movement of lymphatic fluid Lymph nodes behind the knee If a problem occurs in the foot, the glands near the knee will trap and attempt to destroy the invading micro - organisms. In doing so the gland will often become swollen, and may be felt on physical examination. If the organisms get through the glands in the knee area, they may well be trapped by the glands in the groin. All regions of the animal’s body are protected in a similar way, with glands being found throughout the body. The lymph nodes have three important functions, each carried out by different types of cells. Filtration and destruction of foreign organisms Production of lymphocytes Site of contact for foreign organisms with immune cells to produce antibodies These lymph nodes contain scavenger cells that are called macrophages which will consume and destroy micro-organisms. In addition, the lymph nodes are the site for the production of lymphocytes, white cells that are found both in the lymph nodes and are added to the blood and found in the circulation. The lymphocytes have an important defence role by being involved in the process that produces antibodies. Contact with the invading micro-organisms occurs in the lymph nodes, stimulating the production of antibodies. This process will be discussed shortly. 117 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 THE SPLEEN Spleen The spleen is an organ found in the abdomen of animals. It has a similar structure to a lymph node, but instead of filtering tissue fluid, it acts to filter the blood, destroying any organisms that find their way into the blood stream. It does have other functions, and animals are able to function normally should the spleen be removed. In review: Inflammation Non - Specific Lymphatic system Spleen Defence in the body Specific 118 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 SPECIFIC RESPONSES The non - specific responses of the body will be effective against common and mild disease causing organisms. However a more damaging organism may not be so easily overcome, and another mechanism described as the immune response comes into action. There are two main features of this immune response. 1. They are active against individual organisms. That is they are specific against a particular organism. For example, a dog may raise a response against the distemper virus. This will be specific against this virus, and will not give any protection against another organism such as parvovirus (that causes gastro - enteritis). The animal will have to mount a new response to the parvovirus infection. 2. These responses have a memory. Should an animal get a disease and produce a response to a particular organism once, then should the animal come into contact again with this disease, a very rapid response will occur, usually preventing any disease from occurring. All animals will mount an immune response to an infection, but when an animal is first exposed to a new organism, it takes some time to produce the response; some animals will be able to overcome the infection with only mild disease signs. In the case of distemper in dogs, many animals will show signs of the disease when first exposed. Some will recover with only mild signs of the disease such as fever, but in others the signs may be severe and include convulsions and even death. Should the animal again be exposed to this distemper virus perhaps a year or so later, the immune system will immediately respond. The body will usually quickly overwhelm the infection this time with the animal showing no signs of disease. This is due to the memory effect. 119 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 This immune response functions in two ways Production of antibodies Immune response Cell mediated response PRODUCTION OF ANTIBODIES The body recognises the structures on the surface of invading organisms, each different organism having a different surface structure. These structures are described as antigens. These antigens are recognised as being foreign and the animal responds by producing antibodies to the particular antigen (or organism). The recognition of foreign is important, or else an animal would be producing antibodies to all the structures in its own body. This is one of the main problems with transplants in humans, where the transplant material (such as a heart) is recognised as foreign by the body and an immune response occurs to destroy the foreign organ. Drugs are used to suppress (reduce) this response, but these drugs suppress the immune response in general, often leaving the patient susceptible to infections. The body produces antibodies which are protein molecules (a chemical made up of protein) that are effective in destroying the invading micro - organisms. These antibodies attach to the organism or any toxins (poisons) they may produce, by recognising the antigens of that organism or toxin. The antibodies act by damaging the structure of the organism or toxin, or help cause macrophages to destroy them. It is thought that the lymphocytes that are found in the lymphatic system and the blood are fundamental in this response. When encountering a new antigen, some change into a new cell type called a plasma cell which produces the antibodies. Other lymphocytes stay as 120 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 lymphocytes and retain the memory of the particular antigen as protection against another infection by that organism at a later time. Foreign Organisms Lymphocyte ANTIBODIES Lymphocyte with memory Plasma cell MEMORY Lymphocytes are responsible for the memory process that protects an animal should it encounter the antigen again. Usually this memory is long lasting and may last for many years. In some cases memory is short lived and the animal may again be ill with the same disease a second time. Vaccination is based on this memory mechanism. An animal is given a dose of the antigen for a particular disease, causing the immune response. The antigen used is usually killed organisms, or living organisms that have been slightly altered so that they do not cause the disease. However should the animal encounter the real organism (disease), the response produced by using a vaccine (given at an earlier time) enable the animal to mount a rapid response, killing the invading organisms and avoiding the disease. For instance, the vaccine for preventing tetanus in animals is used by injecting an animal with liquid that contains tetanus bacteria that have been changed so that they cannot cause the disease, but still causes the lymphocytes to produce antibodies and memory cells. 121 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Living vaccines will generally produce a better immune response. Re - vaccination is usually required at regular intervals to maintain an adequate level of protection CELL MEDIATED RESPONSE Some lymphocytes demonstrate a direct action themselves, not involving antibodies, showing the same memory as discussed above. This process is particularly important for infections inside the cells (such as tuberculosis), where antibodies do not easily reach. These lymphocytes are also involved in the graft rejection process previously mentioned. Often both antibody and cell mediated immunity work together in protecting the animal from disease. OUTCOMES OF DISEASE Should an animal acquire a disease, regardless of the cause, there are three main outcomes possible for an animal. Resolution / recovery Outcomes Chronic condition Death 122 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 RESOLUTION / RECOVERY An animal may be able to return to normal health showing no signs of the disease. This is described as recovery. In many instances some evidence of the disease remains, but the animal has no ill effects in the long term. This is called resolution, a good example here could be an animal that has a broken bone repaired, and although stuck with some swelling for life (from the repaired bone), the animal has no ill effects from the injury once healing is complete. Some animals may recover fully from an infectious disease, but still have the organisms present in or on the animal. This animal may still be able to spread the disease to other animals, and present a special challenge in the control of infectious disease. These animals are called carriers. CHRONIC CONDITION This refers to conditions that last for longer periods sometimes indefinitely and have some harmful effects on the animal. Diseases such as tuberculosis may affect an animal for years causing ill health. Allergies may persist for the life of an animal; flea bite allergies are common in dogs and are a good example of a chronic condition. Arthritis is another chronic condition that is commonly seen in animals and people. 123 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 DEATH Some conditions are so severe that the life of the animal is lost. Many infectious diseases will claim the life of an animal. Distemper in dogs and tetanus in horses are examples. Of course many other congenital and acquired diseases can cause the death of animals. Many a dog has loved chasing cars until they actually catch one!!! 124 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 PROGNOSIS Is the term uses to describe the likely outcome of a disease. Should an animal contract a disease, then the prognosis will indicate what is likely to happen to that animal. Some terms that are used with prognosis are shown in the table below. Prognosis Excellent prognosis Meaning The animal is likely to Kennel cough in dogs recover fully Fair prognosis Poor prognosis Grave prognosis Examples Ringworm in cats The animal will most likely Strangles in horses recover A broken femur in a cat The animal may not recover, Parvovirus infection in dogs but some chance exists Tetanus in sheep The animal is seriously ill Severe trauma and will not likely recover Lung cancer The prognosis is determined by considering what happened to other animals with a similar disease. It is not always accurate, some animals that are gravely ill will sometimes recover, and other animals that are only slightly ill, may be overcome by the illness. Such is the course of nature!!!! 125 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 126 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 Vet Medical Nursing 1 Worksheet 3 Completing this study sheet will help you to prepare you for Assessment 3. You do not need to submit this worksheet. 1. Review the process that is used to obtain a diagnosis for an animal that is sick. Use clear headings and write in note form. _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ 2. Write a brief explanation of why one particular set of signs in a sick animal does not necessarily indicate one particular disease. _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _________________________________________________________________________ 127 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 3. Describe 3 ways in which the skin acts to prevent infectious micro - organisms entering the body ___________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ 4. Describe how cilia in the respiratory tract act as a barrier to infection. __________________________________________________________________________ _________________________________________________________________________ ___________________________________________________________________________ 5. List four chemicals that mucous membranes produce that may be harmful to micro - organisms 6. ________________________ _____________________________ ________________________ _____________________________ List the five main signs of inflammation ________________________ _____________________________ ________________________ _____________________________ ________________________ 7. Name the important chemical released by cells during inflammation. __________________________________________________________________________ 8. 9. Name the term used to describe inflammation of the skin ________________________ the bladder ________________________ Is inflammation always caused by an infection? ___________________________________________________________________________ 10. Explain how lymph nodes function in the defence process _________________________________________________________________________ 128 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 _______________________________________________________________________ _______________________________________________________________________ 11. Describe the main function of the spleen ___________________________________________________________________________ ___________________________________________________________________________ 12. List the 2 main features of the immune system _________________________________________________________________________ _________________________________________________________________________ 13. Name the 2 ways in which an animal’s immune response functions. _________________________________________________________________________ _________________________________________________________________________ 14. Explain what antigens are _________________________________________________________________________ _________________________________________________________________________ 15. Name the white blood cells that are important in initiating the immune response ________________________________________________________________________ 16. Name the cells that produce antibodies _________________________________________________________________________ 17. Explain how the process of vaccination affects the animal’s body to prevent disease. _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ 129 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 3 18. Describe the cell mediated response of an animal __________________________________________________________________________ _________________________________________________________________________ __________________________________________________________________________ 19. Name the 3 possible outcomes for an animal with a disease ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 20. Explain what a carrier animal is __________________________________________________________________________ __________________________________________________________________________ ___________________________________________________________________________ 21. Explain the meaning of a chronic disease and give on example of a chronic disease that affects animals __________________________________________________________________________ __________________________________________________________________________ ___________________________________________________________________________ 22. Explain prognosis and discuss two terms that may be used with a prognosis ___________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ Please complete and submit Assessment 3 Now 130 Applied Vocational Training Veterinary Medical Nursing 1 CHAPTER 4 Treatment & Prevention of Disease Outline Treatment of Disease Prevention of Disease First Aid Transporting an unconscious patient Instructions for this chapter Complete all questions and exercises found in this chapter using your notes and information you might research elsewhere. Assessment for this chapter Complete and send in Assessment 4 131 132 Chapter 4 Chapter Four Outline Treatment of Disease Medical Care Generally supporting the animal Clean comfortable environment Food & water Exercise & grooming care Care & affection Treating the signs of disease Specific Treatments Surgical Treatment Prevention of Disease Breeding animals to avoid disease Keeping animals healthy Preventing disease Emergency Treatment & First Aid Treatment Cardio-pulmonary Resuscitation Controlling External Haemorrhage Some First Aid Treatments Dressing minor wounds Splints Housing an injured animal Transporting an Injured Animal 133 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 134 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 TREATMENT OF DISEASE There are many different approaches to the treatment of animals that have a disease. Only the conventional ones that are proven to be effective will be discussed in this section. Usually the approach taken to manage a disease can be described as either medical or surgical. This is a fairly broad generalisation with some treatments involving both the use of medicine and surgery. Medical Treatment of disease Surgical 135 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 MEDICAL CARE Medical care is the care given to an animal that does not involve surgery, and there are several aspects to this type of care. Often medical care may just involve the use of a specific medicine to halt the disease; however there are many more possibilities that can be considered. Generally medical care can be considered as doing one of three things 1. Generally supporting the animal 2. Treating the signs of disease 3. Specific treatments Generally supporting the animal There are many actions that can be taken to ensure that the animal has its best chance of recovering from disease. Depending on the severity of the disease, various levels of care may be required. An animal with an injury to a leg may just require rest, whereas an animal with a severe viral infection of the bowel may need a great deal of care. Some general considerations are: clean comfortable environment minimise stress food and water exercise and grooming care care and affection ( tender loving care “ TLC ” ) These may appear to be common sense, but careful consideration of these factors may considerably alter the outcome of a disease. 136 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Clean comfortable environment A sick animal should be in an environment that is clean, so as to minimise the occurrence of any secondary problems (such as infections from bacteria in the faeces, or scalding from urine). Animals may well feel happier in a clean environment, and are more likely to recover from disease. Dogs in a clean kennel. Image Canine’s Canyon Boarding Temperature of the environment is critical in some situations. Young animals (such as orphans) may well die due to a cold environment. Provision of warmth is a basic part of caring for any sick animal. Animals in shock will often respond favourably to warmth. Of course if the temperature is too hot, stress will be placed on the animal as well! One example of providing warmth for an animal might be the situation where a lamb has contracted pneumonia (infection of the lungs) during cold, wet weather. Antibiotics may be useful in killing bacteria involved in the infection, but if the animal is not placed in a warm, sheltered environment, it will very likely die, despite treatment with antibiotics. Minimise stress There are many things that can be done to minimise the stress placed on an animal. The environment as discussed above may be critical. Other factors such as keeping the noise levels down and having appropriate lighting may be important. Some animals such as fish may require 137 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 particular hiding places, other animals may not get on with animals of a different species, or even animals of their own species. Attending to these matters will reduce the stress placed on the sick animal and improve its chances of recovery. Food and water Animals need food and water to survive, ensuring a good quality supply of food and water for an animal that is sick is important. If an animal has stopped feeding and drinking, it may be necessary to force feed the animal or even supply fluids and nutrients via a stomach tube or into the circulation (using a drip) Exercise and grooming care Gentle exercise, such as a walk outside may improve an animal’s recovery. Of course some animals that are sick require strict rest. Grooming and the control of external parasites will likely make an animal feel better. Some external parasites may stress an animal considerably by causing irritation and even sucking its blood. Care and affection As with humans, a little care and affection can go a long way in making an animal feel better, and may well improve its chances of recovery. The type of care discussed here should be considered in all cases of sickness, and appropriate care taken. Of course more specific care may be required to overcome an illness, but by taking care of these basics, often the outcome of a disease can be improved and cause specific treatments to be more effective. 138 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Treating the signs of disease Often treatment of a disease is based on alleviating (reducing or removing) the signs of the disease. A good example here is how people deal with the flu. Often aspirin is taken to reduce the fever and headache, drugs such as pseudephedrine are used to dry up nasal secretions, and codeine might be used to suppress the cough. All of these treatments are used to alleviate the signs, but do not have any effect on the viral cause of the disease. The body is left to fight off the infection on its own. Treatments may involve the use of medicines, or may involve treatment with other methods. In some cases the treatment may actually completely affect a cure. For instance an animal that is badly dehydrated due to heat exposure without access to water, may be cured by the use of intravenous fluids. There are usually several different methods that can be used to treat a particular sign of illness. The table below illustrates a few of these types of treatment. Disease signs Treatments used Vomiting anti - emetic ( anti - vomit ) drugs Diarrhoea dietary control anti - diarrhoeal medication Pain pain relievers Muscle inflammation anti - inflammatory drugs physiotherapy acupuncture Constipation laxatives enema Dehydration intravenous fluids Hypothermia warmth ( low body temperature ) warmed intravenous fluids Skin allergies soothing washes anti - inflammatory drugs Fits or seizures sedatives Coughing cough suppressants 139 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Study Exercise Consider some signs of disease that are seen in animals (or humans) Write down six of these below and treatments that may be used to alleviate these signs. Signs of Disease Remedy used Specific treatments Other treatments used are quite specifically aimed at the cause of disease. For example, antibiotics will be used to destroy bacteria that may be affecting an animal. Again, specific treatments may be based on the use of medication (drugs) or be by other methods. 140 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 The table below illustrates a few of these types of treatment. Cause of disease Treatments used bacterial infections antibiotics infestations with worms anthelmintics ( anti - parasite medications ) vitamin deficiency vitamin supplements dietary change external parasites insecticides grooming heart disease cardiac stimulants reduce exercise dietary modification snake bite anti - venene Cancer chemotherapy radiation therapy Diabetes hormone replacement dietary modification The examples above offer a few suggestions of treatments used. Often combinations of treatments will be used, involving supportive care, treating the signs of disease and specific treatments. It is important to realise that one animal may show many varied signs of disease and have more than one disease at a time. 141 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 SURGICAL TREATMENTS Often it is decided that the best option for treatment of a particular disease is to have surgery performed. Surgery is generally considered to mean using an operation involving manual cutting into an animal. It is generally restricted to trained Veterinary Surgeons as it involves special skills and often the use of anaesthesia. There are many diseases that are best treated surgically. Often diseases are treated by a combination of medical and surgical treatment. Supportive care is an essential backup for any surgical treatment. A few examples of conditions that may be treated surgically are shown below. Disease severe trauma Surgical Treatment suturing ( stitching ) damaged tissue orthopaedics ( repairing damaged bones ) skin cancer excision ( cutting out ) the tumour blockage of bowel laparotomy ( incision into the abdomen ) removal of obstruction difficult birth caesarean section ( opening the uterus ) infected abscess opening and drainage of abscess badly damaged tooth tooth extraction bladder stones cystotomy ( cutting into the bladder ) ulcer of the cornea suturing the eyelids closed 142 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Study Exercise Consider some diseases that are seen in animals (or humans) Write down six of these below and surgical treatments that may be used. Disease Surgery Used Some surgical terms - otomy - ectomy a suffix used to indicate cutting into. Some examples are cystotomy cutting into the bladder gastrotomy cutting into the stomach a suffix used to indicate removal of tissue. Some examples are hysterectomy removal of the uterus splenectomy removal of the spleen plastic surgery surgery used to correct the shape and appearance of damaged tissues 143 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 cosmetic surgery surgery used to artificially improve the appearance of an animal, often for the purposes of showing. Cosmetic surgery is often not approved of by Veterinary Surgeons. elective surgery surgery that is not urgent and is performed at a convenient time. Sterilisation of animals falls into this category. Surgery is generally only used for the treatment of animals when it is considered that other means of treatment will not achieve a satisfactory result. This is because surgery is a major consideration and in itself may cause risk to the animal through both the anaesthesia and surgery. A note about euthanasia. Euthanasia is the humane killing of an animal. This means that an animal is killed without causing undue pain or distress. Euthanasia is used for animals where treatment of a condition is not practical or likely to be helpful. In small animals, euthanasia is performed by injection of a barbiturate drug. In farm animals they are usually shot in the brain. Both methods bring about a quick death. 144 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 DISEASE PREVENTION Much has previously been discussed about the relationship between stress and disease. Keeping the stress that is placed on an animal to a minimum will improve its chances of avoiding disease. However, not all disease can be avoided, many cattle have died from a bolt of lightning, and there is little that can be done to prevent that!!! There are some considerations for preventing disease or ensuring the good health of an animal. One way of looking at these is to consider three aspects. Breeding animals to avoid disease Keeping animals healthy Preventing disease BREEDING ANIMALS TO AVOID DISEASE It is possible with animals to use parents that are of good stock and avoid breeding with parents that are of poor quality and are known to be carriers of disease. Many responsible breeders are using programs to eliminate diseases that are known to be inherited. Hip dysplasia in dogs and immune deficiency in horses are two diseases where programs to minimize or eliminate them exist. There are dozens of other examples. Inbreeding involves the breeding of closely related individuals, and if used too much can produce animals that are weak and susceptible to disease. KEEPING ANIMALS HEALTHY This includes all the areas discussed previously in the medical treatment of disease for supportive care. Animals that are kept well are less stressed and much less likely to suffer disease. In review the important considerations are: Good nutrition Housing / pasture that is clean, with adequate room 145 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 The animals social needs are met ( no overcrowding, no inappropriate mixing of animals ) PREVENTING DISEASE Using specific methods to prevent disease can be important in an animal health program. Such methods may include Vaccination against infectious diseases Regular treatments against parasites Good general hygiene Avoiding contact with other animals that are ill can also be most effective. The isolation and quarantine of animals that are unwell is most important in preventing disease spreading to other animals. Other methods of avoiding diseases can be used. If infectious animals are housed near well animals, the sick animals should always be handled last of all in a routine, so that people and fomites do not carry disease from the sick to the healthy animals. Cleaning and disinfection of people and equipment after handling sick animals should be routine. Of course, in the event of an outbreak of an infectious disease, it is preferable to isolate (move to a separate building or area) infected animals. All new animals entering a facility should be isolated for several weeks and handled as if they had an infectious disease, until it is clear they are in good health. One example of these other methods is in the control of myxomatosis, which is a serious disease affecting rabbits that can be spread by mosquitoes and fleas. Keeping rabbits in insect proof areas can be most effective in preventing this disease. 146 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 EMERGENCY TREATMENT & ROUTINE FIRST AID An emergency is a life threatening situation for an animal. Sometimes it is difficult to decide whether a situation is life threatening. If in doubt, seek professional help. No Veterinarian is going to mind if you are over cautious in the care of your animals The table below indicates some conditions that are emergencies and require immediate attention, and some conditions that are not emergencies, but should be attended to as soon as possible. An emergency should be dealt with at that time, whether it be a Sunday or 2.00 am in the morning. The non - urgent cases should be dealt with when a clinic is open (not usually later than the next day) Emergencies Non-urgent Unconsciousness Abscess Collapse Not eating or drinking Uncontrollable haemorrhage ( bleeding ) Lethargy Snake bite Small wounds or controllable haemorrhage Poisoning with insecticides or snail baits Mild lameness Convulsions or seizures Blood in the urine or faeces Prolapsed eye Mild burns Severe lameness that has come on Diarrhoea suddenly Severe trauma : open wounds or fractures Ear infection or burns Emergencies Non-urgent Difficult breathing Coughing / sneezing Snake bite Constipation Straining to urinate ( if male animal ) Excessive itching Difficult birth ( dystocia ) Swelling of the abdomen ( bloat ) Swelling on body 147 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 It is not always difficult to judge whether an illness is an emergency. Many of the situations listed above are quite clear, but the history may also change the perspective on an urgent case. To illustrate this, a male cat that is straining to urinate may well have a blockage of the urethra that can quickly result in no urine being passed and the possible death of the animal. This is an emergency, yet a female cat with the same signs will likely have cystitis, an infection of the bladder, that is not urgent or life threatening. Diarrhoea in a young pup that has blood in it could indicate the presence of Parvovirus infection, a potentially deadly disease that needs urgent attention. Yet another pup may get diarrhoea because it has been drinking milk, this of course is not urgent. As you can see, it is not always easy to come to a decision. Only a few examples of emergencies have been given in the table above, many other situations can be urgent, and specialised knowledge may be needed to make that decision. If you are unsure, seek professional advice, don’t wait. 148 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 CARDIOPULMONARY RESUSCITATION Cardiopulmonary resuscitation (CPR) is used when an animal has collapsed and is unconscious. It has stopped breathing and its heart has stopped. Without treatment, this animal will not recover and die. There are many circumstances where this could come about, including: trauma ( such as with a motor vehicle accident ) poisoning heart disease during anaesthesia heat exhaustion There are 3 objectives of CPR and they are often known as A B C A Establish an open airway B Provide ventilation to replace breathing C Compress the heart to create circulation Depending on the size and species of animal, CPR may be used at a different pace. Generally the larger the animal, the slower the heart rate and breathing, and the slower CPR is performed. Before commencing CPR you should always ensure you are in a safe situation yourself (eg off the roadside) 149 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Airway Clear the airway by extending the animals neck, look into the mouth and throat to ensure it is clear. Remove any foreign material (such as food or vomit). Breathing An animal may be respirated by blowing into the nose (making sure the mouth is closed). Use a cloth or an inverted funnel, direct contact with an animal’s nose and your mouth is not recommended. Another method is to compress the chest wall by pressing on the ribs of the animal when it is on its side. This is less effective than blowing. For a medium sized dog, give 3 full breaths in 5 seconds Then one breath every 5 seconds. Continue until animal breathes unaided Circulation Check to see if there is a heartbeat by feeling the chest wall or checking for a pulse. If the heart is not beating, commence external cardiac compression (ECC) by laying the animal on a flat surface, and using both hands press on the chest wall above the elbow of the animal (as high towards the head as possible ). For a medium dog, Give 10 - 15 quick compressions (one every second or two) then stop and give one breath. If two people are available, give 5 compressions and then one breath. Check every minute or so to see if the heart has restarted. Seek Veterinary help as soon as possible. In a veterinary hospital, the animal would be intubated (a tube placed into the airway) and respirated with oxygen. If after 4 minutes the animal does not recover, the animal can be considered dead, and CPR should be stopped. 150 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 CONTROLLING EXTERNAL HAEMORRHAGE Bleeding on the surface of the body is usually caused by trauma of some kind. In most cases bleeding can be controlled by applying direct pressure to the area that is bleeding. Use a wad of gauze (not cotton wool that tends to leave fibres) and place this over the area of bleeding, holding it there with firm pressure (a folded handkerchief can be used if no gauze is available). Keep the pressure on for five minutes, do not dab and do not peek. If possible elevate the area above the level of the heart. Check after 5 minutes to see if the bleeding has stopped, if it has not, continue for another 5 minutes. LIM B Site of bleeding Gauze pad APPLY FIRM PRESSURE 151 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 If bleeding persists, put another wad of gauze over the first, surround the area with cotton wool (at least 3 or 4 cm thick) and then bandage with an elastic bandage to create pressure. Then seek Veterinary advice. A pressure bandage should not be left on for more than a short time unless advised or applied by the Veterinarian. In the case of a limb, the whole limb should be wrapped in cotton wool, then the whole limb wrapped with an elastic bandage that creates a firm pressure Cotton wool LIM B Gauze pads elastic bandage LIM B Site of bleeding FIRST AID FOR SOME EMERGENCY SITUATIONS The study of first aid can be quite extensive, and treatments involve a great degree of skill. Always seek professional help after quickly giving first aid. Some examples of first aid procedures are shown in the table below Condition First Aid Heat stress Place the animal out of the sun. ( hyperthermia ) Cool with running tap water from a hose Seek immediate Veterinary attention Prolapsed eyeball Cover eye with moist gauze pad Seek immediate Veterinary attention 152 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Snake bite Put a pressure bandage on the limb or area that has been bitten Seek immediate Veterinary attention Convulsions Restrain animal on a stretcher or flat surface away from obstacles Seek immediate Veterinary attention Open wound Cover with moist gauze pad ( add antiseptic to pad if available ) Seek immediate Veterinary attention Poisoning by eating Remove poison from animals reach snail baits or Induce vomiting if possible ( ipecac syrup or salty water may work ) insecticides Seek immediate Veterinary attention Poisoning by Wash animal thoroughly to remove as much poison as possible contact on skin with Seek immediate Veterinary attention poisons Fracture of limb Immobilise using a splint Restrain animal to stop use of limb Seek immediate Veterinary attention Dressing Minor Wounds There is a plain effective method of dressing minor wounds such as small lacerations, burns or puncture wounds. Basically 3 steps are involved: 1. Dressing 2. Padding 3. Bandaging Dressing The dressing should be sterile if possible; gauze is usually the best material to use as it will not stick to the wound. It should be several layers thick It should cover the wound and an area outside the wound. Can be used with an antiseptic. 153 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Wound Dressing Padding The padding should be soft to avoid damage to the area and absorbent to soak up any discharges. It should be used generously to protect the area Cotton wool is most suitable and useful With a limb, at least one layer of cotton wool should surround the leg on top of the dressing. Dressing Padding 154 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Bandaging The whole dressing should be held together with a bandage. Usually for a light dressing, an elastic bandage is useful. Often these bandages can be secured with a metal clip. Apply pressure that is firm, but not tight Bandage only over the padding Overlap each layer by about a third to a half Use an adhesive tape to secure the bandage Should a dressing be needed low down on a limb, it is best to enclose the toes in the bandage. This is to avoid excessive swelling of the toes which can occur if they are not included. Padding should be put around and in between the toes, before the bandage is put on. These types of dressings should be changed every few days at the longest. It may be preferable to check a dressing each day. If a dressing becomes excessively wet, then it should be changed. 155 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Cotton Wool SPLINTS Are used to provide support for an area on a limb that is injured. They may be used to treat sprains and some fractures. Limb They usually involve a dressing that has a very thick layer of padding with some strengthener built in the bandage on top of the padding, but underneath or within the bandage. Pieces of metal or wooden rod may be useful. In an emergency, rolled up newspaper can be used. A Robert Jones bandage is a very useful splint that can be used to immobilise a limb. Often a Robert Jones dressing will be used in place of a cast (usually made of hard materials such as plaster of paris, that cannot easily be removed), where the dressing needs to be regularly changed. It consists of an extra thick layer of cotton wool being used as padding, which is then tightly wrapped with an elastic bandage to create a firm splint. 156 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 HOUSING SUITABLE FOR AN INJURED ANIMAL An injured animal will need to be confined, observed closely and it may not be able to urinate and defaecate outside of its area. So special considerations for injured animal housing are: Animal should be warm, dry and comfortable Area should confine the animal not allowing too much room for walking around and be no bigger than necessary The housing should be positioned to allow easy monitoring It should be easy to clean It should be quiet Cat recovering from surgery in a cage 157 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 TRANSPORTING AN UNCONSCIOUS ANIMAL Care needs to be taken when transporting an unconscious animal. There are several considerations. The airway must be kept open. Pressure must not be put on the neck of the animal or the mouth and nose obstructed. The animal should be secured. If it is a small animal, then it can be securely carried by placing an arm in front and behind. If it is a large animal, it may need to be placed on its side on a flat board or blanket, and then carefully moved. The head and neck should be extended to ensure it can breath. An animal not being carried should be tied so that it cannot fall during transport. Padding may be needed if the animal is to be transported any great distance. This should be placed under the head, shoulder and hip areas to avoid pressure damage to nerves. 158 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 An animal that is unconscious may not be able to regulate its body temperature as well as normal, so it should be kept warm. It may urinate and defaecate during transport, so ensure the animal and its transport can be easily cleaned. Cats should always be caged. Should they recover during transport; a distressed cat can be difficult if loose. 159 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 160 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 Vet Medical Nursing 1 Worksheet 4 Completing this study sheet will help you to prepare you for Assessment 4. You do not need to submit this worksheet. 1. List the 3 main principles of medical care ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 2. List four actions you could take to provide supportive care for an animal. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 3. Explain how providing a clean comfortable environment for a sick animal may assist in its recovery. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 4. List 3 examples of treating the signs of a disease. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 161 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 5. List 3 specific treatments for disease. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 6. List four diseases where surgical treatment may be used ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 7. Explain how it is possible to breed animals to avoid disease. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 8. Name 3 methods used to prevent disease in animals. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 162 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 9. Consider you have an outbreak of a disease in a flock of valuable llamas. There is no specific treatment for this disease. What general steps could you take to ensure as many animals as possible return to normal health? _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ 10. In the table below, list four examples of emergencies and four examples of cases that are not emergencies, but should receive attention as soon as possible. Emergencies Not Emergencies 163 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 11. What action should you take for a sick animal that you are unsure whether it requires urgent treatment? ___________________________________________________________________________ ___________________________________________________________________________ 12. Briefly describe the ABC of cardiopulmonary resuscitation. How would you perform this on a medium sized dog? ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 13. Draw a diagram to explain how you would control external haemorrhage on a limb. 164 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 14. Name the three steps involved in dressing a minor wound. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 15. Describe four considerations when housing an injured animal. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 16. Describe four considerations when transporting an unconscious animal ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Please complete and submit Assessment 4 Now 165 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 4 166 Applied Vocational Training Veterinary Medical Nursing 1 CHAPTER 5 Some medical topics Outline Identification of general clinical equipment Maintaining the consulting room Restraint of patients Administer medication Preparation of vaccines Bandages, splints and cast care Preventing mutilation of self or dressings Nebulisers Handling biological wastes Euthanasia and disposal of pets Instructions for this chapter Complete all questions and exercises found in this chapter using your notes and information you might research elsewhere. Assessment for this chapter 167 Chapter 5 168 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Chapter Five Outline Identification of general clinical equipment Maintaining the consulting room Restraint of patients Administer medication Preparation of vaccines Bandages, splints and cast care Preventing mutilation of self or dressings Nebulisers Handling biological wastes Euthanasia and disposal of pets 169 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 170 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 IDENTIFICATION OF ANIMAL TREATMENT EQUIPMENT You should be able to identify and describe the use of thermometers, stethoscopes, syringes and needles. THERMOMETERS In chapter 1 the use of thermometers was discussed. Here we shall briefly look at the different types of thermometers commonly used in practice. There are two rectal thermometers commonly used in practice: Mercury thermometer Digital thermometer Mercury thermometers are made from glass so care must be taken not to drop them as glass is a hazard as is the mercury contained within the thermometer. Mercury thermometers may take over 30 seconds to register the animal’s temperature. Digital thermometers are battery operated with a reading given after sometimes as little as 10 seconds. It is important to set the thermometer in Celsius rather than Fahrenheit which may be the units of temperature used in some countries. Digital thermometer showing temperature reading in Celsius As discussed in Chapter 1 the temperature is normally taken by the rectal method however there are also available thermometers that take the animal’s temperature via the ear. These ear thermometers are often extremely quick but must be designed for animal use to be accurate. 171 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 An aural (ear) thermometer. The narrow end is gently placed into the external ear canal of the animal INJECTIONS Hypodermic syringes are used to hold solutions for injections. The term hypodermic means “under the skin”, these devices are usually just called “syringes” and come in a variety of sizes. They are usually made of plastic and considered disposable (that is they are thrown away after one use), although it is possible to sterilise them after use for a few times. They are supplied pre sterilised in a plastic wrapper. The most common sizes range from 1 ml to 50 ml. They are graduated (markings) from one hundredth of a ml on small syringes, to every one ml on large syringes. The nozzles that connect to the needle when attached can either be found in the centre or on the side of the end of the syringe. 172 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Nozzle Barrel Different positions of nozzles looking from the end of the barrel Small volume syringe Plunger A large volume hypodermic syringe Needles are attached to the syringe to enable the injection through the skin of the animal. Needles are disposable and one use usually causes them to become use, they are rarely reused. They do need to be disposed of into a sharps container. They come pre sterilised and in a plastic wrapper. The smaller the gauge of the needle, the larger the bore (the tunnel which fluid goes through) Some needles 173 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 They are usually found from size 14 gauge (very thick) to about 25 gauge (thin). An 18 gauge needle would commonly be used to collect blood from a horse A 21 gauge needle would commonly be used to collect blood from a dog A 25 gauge needle would commonly be used to inject into a cats vein Hub attaches to syringe Shaft Bevel the sharpened end that is injected into animal When connecting the needle to a syringe that has an eccentric hub ( one at the outside of the barrel), then it is important that the bevel be facing upwards. Correct Incorrect 174 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Various intravenous catheters are used to maintain a “line” into the blood stream for the administration of fluids or medication, these are much better to use than a needle because needles can be dislodged easily and the sharp point can penetrate the other side of the vein. There are three main types: 1. Butterfly Catheter Like needles these have sharp points and can penetrate the other side of the vein if not careful, but due to the plastic “butterfly” piece they are easier to be secured to the limb and less likely to be dislodged. 2. Over-the-needle Catheter The needle is used to direct the catheter into the vein and then removed so the soft catheter is all that touches the vein itself. It is much less likely that infection and irritation will occur with this. This is the common catheter used in fluid administration. 3. Through-the-needle Catheter These are much longer and more appropriate for use in the external jugular vein. They are the only catheters suitable for monitoring central venous pressure. 175 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 OTOSCOPE AND OPHTHALMOSCOPE These pieces of equipment are found in all consulting rooms and are used for examination of the ears and eyes. Otoscope Ear examination Ophthalmoscope Eye examination The nurse is usually required to ensure that this equipment is kept clean at all times. These both have a strong built in light to enable examination of the animal, and the nurse is often relied upon to ensure that batteries used are fully charged so that the equipment can be used at all times. Otoscope Ophthalmoscope 176 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 MAINTAINING THE CONSULTING ROOM (Information regarding this section is found in your text books and in this module) The nurse is usually responsible for ensuring that the consulting room (the room in which patients are examined) is kept in a clean and functional condition. This is extremely important as this is the area where clients will come to with their animals, and form an impression of the service of the practice. An unclean consulting room that is poorly stocked, or with equipment that is not functional, is a sure way of losing clients. Some considerations: At the beginning of each day The consulting room should be cleaned thoroughly The room should smell pleasant. All consumables should be restocked ( such as needles, syringes, swabs ) All equipment should be present and clean (stethoscopes and thermometers have a habit of walking away from the consulting room, often in the pocket of the vet!!!) Rechargeable equipment should be checked. Periodically during the day Check to see that the room is still clean and pleasant smelling. Top up any supplies that are low. RESTRAINT OF PATIENTS All information regarding this section is found in your text books 177 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 ADMINISTERING MEDICATION Medicines can be given to the animal via various routes: Orally (via the mouth) Rectally (an enema or suppository) Parentally (via injection) Topically (put on skin, eyes, nose, ears or mucous membranes) Which route is chosen depends on the: chemical properties of the drug (e.g. some react with the acid in the stomach and cannot be given by mouth) rate of absorption (e.g. you give the drug by intravenous injection for a quick action) the patient (e.g. some are too aggressive to be given anything orally) convenience for the operator (e.g. not many owners would like to give their pet an injection) Procedure for oral administration tablet (cat or dog): 1. Restrain patient 2. Open the animals’ mouth, either by holding the top jaw and putting a pointer finger in the space next to the canine and pressing on the roof of the mouth OR holding the top jaw with one hand and using the other hand to hold the tablet and by pull down on the jaw. 3. Place the tablet at the back of the mouth 4. Close the mouth and watch for the animal to swallow 178 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Procedure for oral administration of a liquid (cat or dog) 1. Put the liquid in a syringe 2. Hold the muzzle and tilt the head back 3. Place the nozzle of the syringe in the side of the mouth behind the canines 4. Slowly administer the medication 5. Hold the animals head firmly and watch for them swallowing Procedure for administering a subcutaneous or intramuscular injection to a dog or cat 1. Select a sterile needle and syringe and draw up the required amount of drug 2. Restrain the patient 3. Moisten the skin with a spirit swab 4. a. For subcutaneous injection – insert the needle under the skin (commonly over neck or ribs) b. For intramuscular injection – insert the needle at right angles into the muscle (the most common site is the quadriceps), 5. Pull back on the syringe plunger if no blood appears, inject. If blood appears you have entered a blood vessel and a new site must be 6. Massage the injection site 7. Dispose of needle and syringe properly selected 179 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Procedure for administering an eye ointment or eye drops 1. Open ointment 2. Restrain animal 3. Approach the animal from the side with the tube of ointment / bottle of drops so as not to frighten them 4. a. Squeeze a line of drug on the lower inner eyelid. Do not touch the surface of the eye with the nozzle. b. Lift upper eyelid by pushing on eyebrow area upwards and place drops onto white area (sclera) of eye 5. Allow the patient to blink and so disperse the medication over the eye. Procedure for administering ear cleaner for dog or cat and cleaning the ear 1. Restrain animal 2. Hold pinna of ear and place nozzle of bottle (containing ear cleaning fluid) into ear canal and squeeze bottle gently 3. Massage the external auditory meatus (see text) 4. Step back and let the animal shake its head 5. With a tissue clean the external pinna and as far into the ear as your finger can reach 6. Repeat above steps until ear appears clear of debris Procedure for administering medication orally to a horse Most de-wormers come in “dose-syringes” that have an adjustable wheel on the plunger that is used to set the “based on weight” dose. Be careful to take the time to work out your horse’s weight. 1. Once your syringe is ready, approach you horse slowly and stroke your horses of his nose. 2. Once the horse has relaxed, gently insert the syringe into the corner of his mouth, placing the syringe tip over the middle of the tongue and unload the contents. 180 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Once the contents of the syringe are in the horse’s mouth, lift the head up by pressure 3. under the jaw as the horse will tend to shake his head and spit out as much of the medicine as possible Preparation of vaccines Many vaccines are prepared and administered under supervision by veterinary nurses. A few considerations are important. Ensure the vaccine has been stored correctly. Use careful hygiene when preparing a vaccine If the vaccine is presented in a dried form, ensure it is properly mixed with the diluent (usually sterile water). Use vaccines that have been made up immediately as they may lose their effect if left at the wrong temperature BANDAGES, SPLINTS AND CAST CARE A brief introduction to bandages was included in the last chapter, in this chapter we shall expand on the subject. Uses of bandages: Reasons for bandaging an animal include: Protection: this may be from contamination of a wound, or to protect the animal from damaging the area Compression: reduction of swelling, this may also be used to reduce haemorrhage Aid in attaching a splint Immobilization: useful in fractures 181 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 There are typically 4 layers to a bandage: 1. Dressing or contact layer: this is usually non-adherent and is best if it is sterile as it contacts the wound. 2. Layer for absorption. This layer absorbs exudates or blood from the wound. 3. Protective layer (protects wound and holds dressings in place) – usually a layer made of an elasticated material. This is a conforming layer. 4. Covering/protective layer (provides support and protection) Dressings There are many different types of dressings that have different functiond depending on the type of wound. Some common examples include: Paraffin impregnated gauze: examples include paranet or jelonet. This material is oily but does not adhere to the wound. It is available in individual sterile packets or in a container with many dressings. Paraffin gauze Melolin: highly absorbent combination of cotton and acrylic fibre with a thin film on one side. The dressing is applied with the film side to the wound. Melolin dressing: non-adherent 182 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Absorption layer This layer is composed of cotton wool or a synthetic variation (soffban). It absorbs blood and discharges from the wound. It also provides comfort and prevents rubbing by padding the area. Soffban: synthetic absorbent layer Conforming layer This layer keeps the bandage together with its elasticated bandage material. It is usually an elasticated gauze type material but cohesive bandage as discussed next is also sometimes used as conforming bandage. Protective layer Zinc oxide tape – an adhesive, non-elastic, nonconforming tape. Commonly used to hold bandages in place so they don’t unwind. Usually tan coloured. Example is leucoplast. Zinc Oxide tape. Image: Smith & Nephew Elastoplast is another adhesive tape commonly used as a protective layer. It has adhesive on one side and Roll of elastoplast Cohesive bandage: A material that adheres to itself but not to the patient. Can also be used as a bandage but its better use is as a covering material. Examples include Vetwrap and Coban. 183 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Vetwrap a veterinary cohesive bandage Cast Materials Fibreglass – lightweight material that is quick to set and is made using cold water Plaster of Paris – very cheap. Plaster is impregnated into a roll of gauze. Use cold water to wet and then apply. Once dry it sets hard but will soften if it gets wet again. Hexalite – activated by hot water, dries very quickly and is very strong and radiolucent Care of Bandages and Dressing Constant (at least twice daily) checks of bandages should be maintained. One should look for odour, oedema (swelling) and discharge or skin irritation. If you can see the toes or any area above or below the bandage, check to see if there is any swelling as this may indicate that the bandage is on too tight. When going outside for exercise on a lead it is important the dressing does not become soiled or wet. Cover the bandage with plastic but remember to remove it when you come back inside otherwise the bandage will “sweat” and become moist internally. 184 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 PREVENTING MUTILATION OF SELF OR DRESSINGS Elizabethan collars can be purchased or a home-made version can be used. A common bucket with the base removed can be quite effective. For small animals a plant pot can be used. The base is then tied to the animal’s collar using gauze. The handle is discarded Gauze is used to tie onto the collar The base of the bucket is cut off A commercial Elizabethan Collar Nebulisers Nebulisers are devices that atomise medication (make it into minute particles) then introduce it into the air for inhalation. Most people are familiar with the pump Nebulisers used by human sufferers of asthma. Various types are occasionally used to treat animals with respiratory problems. Handling biological wastes All information regarding this section is found in your text books 185 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 186 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 Vet Medical Nursing 1 Worksheet 5 Completing this study sheet will help you to prepare you for Assessment 5. You do not need to submit this worksheet. 1. Describe the two main types of rectal thermometers ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 2. Describe the function of the stethoscope. ___________________________________________________________________________ ___________________________________________________________________________ 3. List the different types of oral (given via the mouth) medication used in animals ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 4. Describe the main advantages of using oral medication ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 187 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 5. Briefly describe the procedure for oral administration of a tablet. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 6. List the various types of topical medication used on animals ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 7. Describe how to administer ointment to the eye of an animal. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 8. Describe how to administer ear drops to an animal. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 188 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 9. List the four main reasons for bandaging an animal. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 10. List the two main types of dressings used __________________________________________________________________________ __________________________________________________________________________ 11. Name and describe the main properties of different bandaging materials __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 189 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 12. Describe two covering materials _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 13. Describe two materials used for casts _____________________________________________________________________ _____________________________________________________________________ 14. Discuss the important aspects of caring for bandages, casts and splints _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ ____________________________________________________________________ 15. List 5 methods of preventing an animal from chewing or licking at a dressing or at itself. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 190 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 __________________________________________________________________________ 16. Using your textbooks draw a diagram showing the difference between subcutaneous, intramuscular and intradermal injections 17. Draw a diagram to illustrate the use of an Elizabethan collar. Please complete and submit Assessment 5 Now 191 Applied Vocational Training Veterinary Medical Nursing 1 Chapter 5 192 Applied Vocational Training Veterinary Medical Nursing 1