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FALL = a sudden, unintenstional change in position causing someone to land at a lower level – other than due to paralysis, seizure or overwhelming force Recurrent falls are defined as those occurring at least 3 times a year. Understand epidemiology of falls in the elderly. Frequency: >65 years: 30% per year > 70 years: 35% per year >75: 40% per year - 50% of nursing home residents fall. Injuries due to falls are the most common cause of mortality in people >75 in the UK. Other groups - young children and athletes - also have high incidence of falling but are less susceptible to injury (have less chronic diseases and age-related physiological changes) and recover more quickly. For a primary care trust and local authority with a population of 320,000: 15,500 will fall each year; 6,700 people will fall twice 2,200 will attend accident and emergency departments or minor injuries units A similar number will call an ambulance 1,250 will have a fracture of which 360 will be hip fractures Identifies and manages factors contributing to recurrent falls/collapse. DAME: Females > males D rugs incl alcohol A ge related cahnges (gait, sensory, vision impairment) M edical (CVD, parkinson’s disease) E nvironental obstacles Internal risk factors Individual characteristics Female gender Low weight Low muscle strength A history of fall in the last year Age (>80 years) Use of an assistive walking device Dependency in activities of daily living Medical conditions Visual impairment: acuity, contrast sensitivity, depth perception, and dark adaptation decline with age. ALSO cataract, glaucoma, macular degeneration, Central retinal artery /vein occlusion can impair vision Orthostatic hypotension Diabetes mellitus Cognitive/psychiatric conditions Central processing decline: e.g. delirium, dementia Depression Impaired cerebral perfusion by: o Diuretics (esp. if dehydrated) o Antiarrhythmics o Antihypertensives (especially vasodilators) Drug causes Alcohol abuse Sedative medication, including hypnotics (may impair co-ordination and cause falls). There is a particular risk of falls in agitated patients with cognitive impairment. Confusion particularly from psychotropic medication may increase the risk of falls. Polypharmacy - the scope for interactions and other effects is increased. Reduced alertness or slow central processing by: o Analgesics (especially opioids) o Psychoactive drugs (especially antidepressants, antipsychotics, and benzodiazepines) Mobility problems Mobility limitation Balance deficit Gait deficit Arthritis External risk factors Inappropriate footwear e.g. slippers Incorrect use of walking aids Pets underfoot Trailing electrical cables Older housing needing repairs Poor lighting, especially near stairs ‘A lifetimes clutter’ Vestibular damage by: Aminoglycosides Lood diuretics (high dose) o o Orthostatic hypotension caused by: o Diuretics (can cause dehydration and may cause urgency and falls) o Vasodilators (including calciumchannel blockers and nitrates) o Alpha adrenergic blockers o Angiotensin-converting enzyme (ACE) inhibitors o Alpha-blockers o Phenothiazines o Tricyclic antidepressants o Levodopa o Bromocriptine o Betablockers o Insulin Unfamiliar environment e.g. new home, hospital Walking while talking or being distracted by multitasking and failing to attend to an environmental hazard (e.g. a curb or step) Rushing to the bathroom (especially at night when not fully awake / poor lighting), and rushing to answer the telephone. Relevant history including from witness of fall/collapse Drug and alcohol history History of fall Was the fall an isolated event or one of many? If many, is there any pattern? How often do they occur? Are they getting more frequent? Does there seem to be any common precipitating factor? Before What caused the fall? o Sometimes the fall is attributed simply to tripping over a loose rug or a trailing electric cable. This is not a medical problem but requires a home safety assessment with a visit by a health visitor. o Or was it loss of balance? ‘Faint’? o If history suggests tripping, ask about eyesight and when last assessed by an optician. What was the patient doing at the time? o Was it something involving exertion? Was the patient in an emotional situation? o Did it involve looking up? Extending the neck to look inside a low cupboard or to do high dusting risks vertebrobasilar insufficiency. o Older people should be discouraged from climbing on chairs or ladders since they are more likely to fall in these situations and will fall further, incurring more serious injuries. o Position (e.g. lying or standing), and, if standing, for how long. Postural hypotension usually occurs on suddenly getting up from sitting or from lying in bed - typically, on getting out of bed to go to the toilet in the night. o Micturition syncope affects men, usually as they stand up at the toilet, attempting to pass urine nocturnally. o Does the patient have a sleep disorder? These are reasonably common in older people and may contribute to the risk of falling. Associated symptoms (e.g. palpitations, shortness of breath, chest pain, vertigo, lightheadedness, nausea, sweating, blurred or tunnel vision, tingling of lips or fingertips) During Was there any loss of consciousness? o o o o A good way of ascertaining this is to ask if the patient remembers falling. Syncope (or blackouts) can be associated with cardiac or neurological symptoms. Was there any warning before the fall? If terms like 'giddy', 'dizzy' or 'faint' are used, explore what is meant. How long did it last? Was there a seizure? o o A witness can describe exactly what happened. If tonic and clonic phases of convulsion - this does not necessarily imply epilepsy from a spaceoccupying lesion or cerebral degeneration, as cerebral ischaemia from poor CO e.g. due to arrhythmia can produce the same. After How was the patient after the fall? o o o o o Whilst they may have felt shaken or injured, features such as weakness that made getting up again difficult, aching muscles or disorientation may indicate the postictal phase of a fit. A witness may be better at ascertaining confusion following the fall and noting how long it lasted. The weakness of a transient ischaemic attack (TIA) may last just a few minutes and leave no residue. Difficulty with language may indicate a TIA. Injuries or incontinence? Incontinence is an unreliable sign of epilepsy and can occur with other causes of loss of consciousness. A bitten tongue is more specific. Did any other injuries occur Patients should be asked whether they were able to get back up without help after falling Review of systems Areas of pain or injury Chest pain / palpitations Previous syncopal events Bloody or tarry stool / heavy menses (anaemia) Vomiting / diarrhoea / excess urination (dehydration / electrolyte abnormalities) Is appetite good and weight steady? How is mobility? Is locomotion becoming slow and laboured? Are mental faculties still sound or is there evidence of cognitive decline? Past medical history Note history of heart disease and diabetes. Is the patient at increased risk of arrhythmias, TIAs, stroke, peripheral neuropathies or hypoglycaemic episodes, for example? Know seizure disorder Risk factors for PE (recent surgery, immonilisation, cancer…) Brittle bone disease / osteoporosis (risk of fractures) Drug history Review all drugs, especially those that may cause confusion or sedation. Most modern treatments for hypertension are less likely to produce postural hypotension than older ones but it may still occur. Alpha-blockers, including phenothiazines can ↓ BP In general, the risk presented by benzodiazepine hypnotics outweighs benefit in the elderly. Ask about illicit and over the counter medications FH - Family history should note presence at a young age of heart disease or sudden death in any family member. Social history What is the history of alcohol consumption? CAGE screening questionnaire Housing / accommodation What is the normal functional status of the patient? Do they require assistance dressing, washing, cooking, for example? Targeted exam of CNS, CVS, MSS and vision. If the fall occurred recently, temperature should be measured to determine whether fever was a factor. Inspection and assessment of any injuries sustained (e.g. bruising, swelling, tenderness, tongue bite) Mental state: Does the patient seem alert and orientated or vague and confused? Oriented to time, place and person? – orientation Spell WORLD backwards – attention Apple, ball, table word recall – immediate recall, short term memory The mini mental state examination may be useful. Decline in mental state may indicate a cause for the falls or it may be the result if head injury has caused a chronic subdural haematoma. Visual impairment: Visual acuity / Snellen chart Light reflexes Colour vision test (perception of the colour red is 1st to go in pathology) Accommodation Visual fields Eye movements / nystagmus Abnormalities in visual acuity should trigger a more detailed visual examination by an optometrist or ophthalmologist. Macular degeneration and visual field defects may predispose to falls. Cardiovascular examination: AF? Variable heart block? Bradycardia? Tachycardia may be a feature of congestive heart failure Lying and standing BP: After 1 and then 5 minutes of standing. *A drop of more than 20 mm Hg in the systolic blood pressure on standing is significant* Listen for bruits over the bifurcation of the carotid arteries but also in the posterior triangle of the neck to detect bruits from the vertebral arteries. If any murmurs: note any change with a Valsalva maneuver, standing, or squatting is noted. Neurological Note muscle wasting that may reflect disuse atrophy, often secondary to arthritis. Brief assessment of the sensory system - ? peripheral neuropathy. Loss of vibration sense can be a marker for posterior column disease with associated loss of proprioception. Basic postural control and the proprioceptive and vestibular systems are evaluated using the Romberg test (in which patients stand with feet together and eyes closed). Tests to establish high-level balance function include the one-legged stance and tandem gait. If patients can stand on one leg for 10 sec with their eyes open and have an accurate 3-m (10ft) tandem gait, any intrinsic postural control deficit is likely to be minimal. Try to reproduce vertebrobasilar symptoms by asking the patient to extend their neck to the full and to hold it for several seconds and repeat with flexion and full rotation to left and right. - Evaluate positional vestibular function (e.g. with the Dix-Hallpike maneuver*) Check coordination (including cerebellar function + nystagmus), stationary balance, and gait. * The Dix–Hallpike test o Is performed with the patient sitting upright with the legs extended. o The patient's head is then rotated by approximately 45 degrees. o The clinician helps the patient to lie down backwards quickly with the head held in approximately 20 degrees of extension. This extension may be achieved by having the clinician supporting the head as it hangs off the table or by placing a pillow under their upper back. o The patient's eyes are then observed for about 45 seconds as there is a characteristic 5-10 second period of latency prior to the onset of nystagmus. o If rotational nystagmus occurs then the test is considered positive for benign positional vertigo. o During a positive test, the fast phase of the rotatory nystagmus is toward the affected ear, which is the ear closest to the ground. The direction of the fast phase is defined by the rotation of the top of the eye, either clockwise or counter-clockwise. Musculo-skeletal: The neck, spine, and extremities (especially the legs and feet) should be evaluated for weakness, deformities, pain, and limitation in range of motion. Note how the patient gets up from the chair. There may be proximal myopathy but in the elderly disuse atrophy is more common. Is gait normal? Is there asymmetry? Some gait abnormalities may be due to arthritis. Look for features that may indicate Parkinson's disease. Performance test NICE recommends the following as being pragmatic tests: - Timed Up & Go Test: Observe for unsteadiness as the patient rises from their chair without using their arms, walks 10 feet, turns around, walks back and resumes a sitting position. A walking aid can be used if required. The process should take less than 16 seconds. Patients who have difficulties are at an increased risk of falling and need fuller evaluation. - Turn 180° Test: request that the patient stand up and step around until they are facing the opposite direction. If more than four steps are required to do this, further assessment is indicated. Abdominal examination Abdomen is palpated for tenderness / ascities A rectal examination is done to check for gross or occult blood. Red flags: Certain findings raise suspicion of a more serious aetiology of syncope: Syncope during exertion Multiple recurrences within a short time Heart murmur or other findings suggesting structural heart disease (eg, chest pain) Older age Significant injury during syncope Family history of sudden unexpected death Investigations Basic blood tests including: o FBC (macrocytosis may indicate alcohol abuse / anaemia) o Hct is measured if anemia is suspected. o U+E (dehydration, deranged electrolytes) o LFTs (may indicate alcohol abuse, especially gamma GT) o TFTs o Vitamin B12 o Random blood glucose (DM – hypo or hyperglycaemia) o Cardiac markers e.g. serum troponin, CK-MB (measured if acute MI is suspected) o hCG - all females of childbearing age should have a pregnancy test. Urinalysis may reveal unsuspected DM (vascular disease, neuropathy, poor vision) Pulse oximetry (hypoxaemia - PE) If hypoxic, do CXR / CT to investigate PE ECG to confirm or suggest (+/- ambulatory ECG): o Arrhythmia e.g. AF o Conduction defects where there is a prolonged PR interval, inferior ischaemia or bundle branch block o Ventricular hypertrophy o Pre-excitation o QT prolongation o Pacemaker malfunction o Myocardial ischemia, or MI Echocardiography is indicated for patients with known: heart failure, atrial fibrillation and valvular disease to assess ventricular or valvular function or to detect atrial thrombus OR with exerciseinduced syncope, cardiac murmurs, or suspected intracardiac tumors (e.g. those with positional syncope). Tilt table testing is done if history and physical examination indicate vasodepressor or other reflexinduced syncope. Stress testing (exercise or pharmacologic) is done when intermittent myocardial ischemia is suspected. It is often done for patients with exercise-induced symptoms. EEG is warranted if a seizure disorder is suspected. Visual assessment by an optician Spinal x-rays and cranial CT or MRI are indicated only when the history and physical examination detect new neurologic abnormalities. Patients with suspected arrhythmia, myocarditis, or ischemia should be evaluated as inpatients. If there are no clinical clues, measuring cardiac markers and obtaining serial ECGs to rule out MI in older patients plus ECG monitoring for at least 24 h are prudent. Any detected arrhythmia must be associated with altered consciousness in order to be implicated as the cause, but most patients do not experience syncope during monitoring. Effects of falls (e.g. fractures) - - - Death Falls are the 6th leading cause of death Some fall-related injuries are fatal. Up to ¼ of frequent fallers die within 1 year of presentation due to underlying cause of falls If neck of femur is #, mortality is: 10% in 1 month, 30% in 1 year (due to immobility, frailty, perioperative complications) Physical injury Over 50% of falls among elderly people result in an injury. Although most injuries are not serious (e.g. contusions, abrasions), fall-related injuries account for about 5% of hospitalizations in patients ≥ 65. Other serious injuries (e.g. head and internal injuries, lacerations) occur in about 10% of falls. More common/severe if lack of protective subcutaneous fat Fractures (#) About 5% of falls result in fractures of the humerus, wrist (including Colles' fracture and dislocations of the wrist), or pelvis. About 2% of falls result in a hip fracture. Fractures of the femur If >80 years old 10% fracture their hips when they fall Fractured hips are a major cause of loss of independence and morbidity and even mortality. Risk increases with: o Osteoporosis o Osteomalacia o Paget's disease of bone o Metastases (to bone) Sequale of a long lie: remaining on the floor for >1 hour after falling Pressure sores Hypothermia Hypostatic pneumonia 50% die within 6 months of the fall, even if there was no injury sustained Renal failure via: 1) Dehydration 2) Muscle breakdown – causes release of creatinine kinase – causing rhabdomyelitis Psychological injury - Loss of self-confidence and independence - Fear of falling (commonest fear in older people) - Decreased activity - Some people may even avoid certain activities (eg, shopping, cleaning) because of this fear. (Decreased activity can increase joint stiffness and weakness, further reducing mobility.) - Physical dependence - Increased medication use - Decreased quality of life - Anxiety and depression - Acceptance / expectation of falls in older age Aware of factors determining good outcomes Understand prevention of falls Muscle strengthening and balance retraining – e.g. physiotherapy. A wide variety of activities (from dancing to Tai Chi) can be undertaken often with the secondary gain of social contact. Activity also slows osteoporosis and helps to prevent weight gain which further impairs mobility. Home hazard modification Withdrawal of psychotropic medication Pacing for those with carotid sinus hypersensitivity Hip protectors - there is no good evidence for the efficacy of hip protectors in preventing fractures in older people who fall whilst living independently. They may be effective in those living in institutional care who are at high risk of hip fracture but acceptance and adherence is poor as they are uncomfortable and difficult to get on and off quickly. NICE recommends that all people at risk of falls should be offered a home assessment and interventions to modify environmental hazards e.g.: - Loose rugs or mats (especially on a slippery floor) - Lighting - Electric leads (trailing across the floor) Wet surfaces (especially bathroom) - Stairs (indoor/outdoor) Referral to an optician can be useful in diagnosis and management. Give advice on appropriate footwear Education on how to fall safely, and how to rise from the floor without help Install personal alarm systems Other interventions (e.g. nutritional supplementation, cognitive behavioural therapy) - efficacy is unknown Fragility (osteoporosis) Ca2+ / Vitamin D Bisphosphonates (hip+vertebral # within 6 months) Fracture prevention triangle Falls MDT e.g. phsyio, OT, medical review, education, exercise, confidence Force Learning ‘how to fall’ Hip protectors Psychopathology of ageing. Geriatric giants: 1) 2) 3) 4) Immobility Incontinence Impaired intellect Instability Psychopathology - Increased depression and anxiety Dementia Delirium Psychological injury of falls General effects of aging re: increased risk of falls - Body sway increases ( Females > Males) - Reaction time slows - Reflexes may be decreased - Walking patterns become more irregular - Visual impairment more common - Decreased proprioception in toes/feet - Decreased confidence Co-morbidities Mechanisms of cellular senescence and somatic ageing • Generation of free radicals – Failure of oxygen scavenging in cells – Environmentally-induced free radicals • Cumulative defects in DNA integrity • Glycation of proteins • Telomeric shortening Correctly categorises cause of fall/collapse. Causes of falls in older people are usually multifactorial but include: Accident and environmental hazards (31%) Gait and balance disorders or weakness (17%) Dizziness and vertigo (13%) Drop attack* (9%) Confusion (5%) Postural hypotension (3%) Visual disorder (2%) Syncope (0.3%) Other specified causes including arthritis, acute illness, drugs, alcohol*, pain, epilepsy and falling from bed (15%) Unknown (5%) Do not forget the possibility of elder abuse. *Drop attacks Drop attacks refer to a fall in which the cause is unknown, the event unexpected and there is no loss of consciousness. Not a term used very often in modern medicine, as it is not a diagnosis. *Alcohol Intoxication causes acute instability. Chronic alcoholism may cause complications predisposing to falls: - Polyneuropathy - Wernicke's encephalopathy - Korsakoff's syndrome Neurological problems TIAs / strokes can cause significant weakness. Parkinson's disease impairs mobility (abnormal posture, freezing of gait, frontal impairment, poor leaning balance and leg weakness are independent risk factors). 10 Diabetes related neuropathy Proximal myopathy (from, for example, thyrotoxicosis, Cushing's syndrome and use of steroids) may impair mobility, particularly rising from sitting. Cognitive impairment may impair co-ordination. Instability (musculoskeletal and neuromuscular causes) Mechanism of fall Gait Example conditions Arthritis Foot deformities Muscle weakness Proprioception Peripheral neuropathy (eg, due to diabetes mellitus) Vitamin B12 deficiency Otolaryngologic function Acute labyrinthitis Benign paroxysmal positional vertigo Hearing loss Meniere's disease Postural and Cerebellar degeneration neuromotor function Myelopathy (eg, due to cervical or lumbar spondylosis) Parkinson's disease Peripheral neuropathy Stroke Vertebrobasilar insufficiency Causes of immobility / instability in joints Osteoarthritis Rheumatoid arthritis Pseudogout Infection Neuronal damage Hemiplegia Peripheral neuropathy Motor neurone disease Paraplegia Fear and anxiety Manipulative behaviour Depression Dementia Pain/stiffness In muscles Myositis Polymyalgia rheumatic Parkinson’s disease Weakness Muscle damage Disuse Myopahty Amyotrophy Hypokalaemia In bones Osteoporosis Osteomalacia Malignancy metastases Reduced effort tolerance Dyspnoea Anaemia Decreased cardiac output Psychological causes Re: falling Attention seeking Apathy and decreased initiative Decreased insight into need to maintain mobility Understand heart rhythm. Able to interpret common ECG abnormalities that may lead to sycope. Able to initiate emergency care for life threatening arrhythmia. - In witnessed syncope, pulses are checked immediately. If the patient is pulseless, CPR is begun and cardiac resuscitation is done. If pulses are present treat according to the arrhythmia Placing the patient in a horizontal position with legs elevated typically ends the syncopal episode if life-threatening disorders are ruled out. Reference: a normal ECG rhythm strip When looking at an ECG, comment on: Rate – under 60bpm is slow, over 100bpm is fast Regularity – look at R-R distances. Are they regular/ occasionally irregular/ regularly irregular/ irregularly irregular P waves – are they present, do they look alike, do they occur at a regular rate, is there one before each QRS PR interval – normal is 0.12-0.20 ms (3-5 small boxes) QRS duration – normal is 0.04 – 0.12 ms (1-3 small boxes) Sinus arrhymias = sinus rhythm is present (i.e. P wave precedes every QRS) but rate is ↓/↑ 1) Sinus bradycardia – < 60bpm 2) Sinus tachycardia – > 100bpm Causes: Physiological in resting athletes, drugs, sick sinus syndrome, hyopthyroidism Causes: Physiological in exercise/ stress ECG: ECG: Rate less than 60bpm Regular rhythm P waves present PR interval and QRS duration normal Rate over 100bpm Regular rhythm P waves present PR interval and QRS duration normal Management: stop/treat causative factors, give atropine. External transthoracic pacing can be used - Isoproterenol can be used to maintain adequate heart rate while a temporary pacemaker is placed. Management: A direct-current synchronized shock is quicker and safer for unstable patients. Inadequate venous return is treated by keeping the patient supine, raising the legs, and giving IV normal saline. Premature ventricular contractions/ ventricular ectopic beats Ventricular ectopics in isolation are not a problem – but can be dangerous if they occur one after the other. Usually benign in younger patients, more serious in the elderly. Exercise can increase or decrease frequency in different patients Causes: × Exercise/ post-exercise × Hormonal changes in females × Ischaemic heart disease × Bundle-branch block × Digoxin toxicity × Reperfusion therapy after MI × × × × × × Electrolyte changes Increased catecholamines Hypoxia/hypercapnia Illicit substances Mitral valve prolapsed Cardiomyopathy × Myocarditis Features: ● Usually asymptomatic ● Palpitations: ‘Heart misses a beat’ / ‘Heart jumps/flutters’ ● Neck or chest discomfort ● Syncope ECG: Aside from ectopic, sinus rhythm Broad QRS complex in ectopic beat– over 0.12 seconds Downward deflection of QRS complex occurs as the depolarisation comes from the ventricles at the back of the heart Treatment: Beta-blocker if symptomatic AV nodal blocks 1) 1st degree AV block - benign Causes: Beta-blockers ECG: Rate – may be slow Regular rhythm P waves normal PR interval prolonged (>0.20 sec) QRS duration normal 2) 2nd degree AV block, Mobitz type I (Wenckebach) – usually benign ECG: Rate – slow Regularly irregular rhythm P waves are present, although some have no QRS With each successive QRS the P-R interval ↑ until there is a nonconducted p wave QRS duration normal 3) 2nd degree AV block, Mobitz type II – may require a pacemaker ECG: R ate – slow R egular rhythm P waves are present, but some not have a QRS complex – if QRS is missed it will be a 2:1 or 3:1 block P R interval normal or prolonged Q RS normal Management: May need a pacemaker 4) 3rd degree AV block Rate – bradycardic Rhythm – 2 independent rhythms are on the ECG: The P waves with a regular P-P interval represent the first rhythm. The QRS complexes with a regular R-R interval represent the second rhythm. P-R interval is variable as there is no coordination between P waves & QRS complexes. QRS broad, over 0.12 seconds. May see downward deflection of QRS as ventricles generate their own rhythm Management: requires a pacemaker as no correlation between P waves and QRS complexes Supraventricular arrhythmias 1) Paroxysmal supraventricular (narrow complex) tachycardia Causes: Common in young women. Structural defects may predispose Features: Palpitations: heart racing or fluttering Lightheadedness Polyuria ECG: ECG shows a paroxysm of narrow complex tachycardia occurring Rate – tachycardic Rhythm – changes from sinus rhythm to a regular tachycardia P waves not present in paroxysm PR interval normal narrow QRS complex during paroxysm – less than 0.04 Management: vagotonic manoeuvres, followed by adenosine or verapamil (if not on Beta-blockers). LT maintenance: beta-blockers / verapamil Ventricular arrhythmias – both are a medical emergency 1) Ventricular tachycardia Causes: If pulse present… × Hyperkalaemia × MI × Ischaemic heart disease Features: Palpitations: heart racing or fluttering Breathlessness Syncope May or may not have a pulse ECG: Rate – over 150bpm Regular rhythm No P waves Broad QRS complex – over 0.12 seconds Downwards deflection of QRS Management: Amiodarone or lidocaine. Cardioversion if haemodynamically unstable. 2) Ventricular fibrillation Features: No pulse – cardiac arrest Management: 1) Defibrillate for 1st time i) Defibrillation monophasic 360J OR ii) Defibrillation biphasic 150–200 J (120J is acceptable, STHFT Defibs start at this) 2) Recommence CPR for 2 minutes, pause to check the monitor – if VF persists defibrillate for 2nd time, as above. 3) Resume CPR for 2 minutes – check monitor. If still VF – Deliver 3rd shock. 4) I.V. administration of Adrenaline 1mg and Amioderone 300mg. Able to perform ECG (See clinical skills info on Minerva) Limb leads use mnemonic "Ride Your Green Bike"(clockwise): Ride - Red - right arm Your - Yellow - left arm Green - Green - left leg Bike - Black - right leg Performs appropriate tests for postural hypotension o Record blood pressure sitting. o Record after 1 minute of standing. o Record afte 5 minutes of standing. *A drop of more than 20 mm Hg in the systolic blood pressure on standing is significant* Able to explain 24 hour cardiac monitoring Holter monitor (24h): A Holter monitor is a machine that continuously records the heart's rhythms. The monitor is usually worn for 24 - 48 hours during normal activity. How the Test is Performed Electrodes (small conducting patches) are stuck onto your chest and attached to a small recording monitor. You carry the Holter monitor in a pocket or small pouch worn around your neck or waist. The monitor is battery operated. While you wear the monitor, it records your heart's electrical activity. You should keep a diary of what activities you do while wearing the monitor. After 24 - 48 hours, you return the monitor to your doctor's office. The doctor will look at the records and see if there have been any irregular heart rhythms. How to Prepare for the Test Tell your doctor if you are allergic to any tape or other adhesives. Make sure you shower or bathe before you start the test - You will not be able to do so when wearing a Holter. How the Test Will Feel This is a painless test. Some people may need to have their chest shaved so the electrodes can stick. You must keep the monitor close to your body. This may make sleeping difficult for some people. You should continue your normal activities while wearing the monitor. There are no risks associated with the test. Why the Test is Performed Holter monitoring is used to determine how the heart responds to normal activity: After a heart attack To diagnose heart rhythm problems When starting a new heart medicine It may be used to diagnose: Atrial fibrillation/flutter Multifocal atrial tachycardia Palpitations Paroxysmal supraventricular tachycardia Reasons for fainting Slow heart rate (bradycardia) Ventricular tachycardia Normal Results Normal variations in heart rate occur with activities. A normal result is no significant changes in heart rhythms or pattern. What Abnormal Results Mean Abnormal results may include various arrhythmias. Changes may mean that the heart is not getting enough oxygen. The monitor may also detect conduction block, a condition in which the atrial electrical activity is either delayed or does not continue into the ventricles of the heart. Considerations Electrodes must be firmly attached to the chest so the machine gets an accurate recording of the heart's activity. While wearing the device, avoid: Electric blankets High-voltage areas Magnets Metal detectors It is very important for you to keep a diary of symptoms. The diary should include the date, time of day, type, and duration of symptoms. Control of upright posture. Occularmotor centre Visual Processed in medulla (pyramidal & extrapyramidal) Proprioception Cerebellum Spinal cord Vestibular system Muscle Loss of proprioception in the feet is a common cause of ataxia. The ataxia markedly improves simply by touching a stationary object or running the hand along the wall (in a sense, replacing the lost sensitivity of the feet). Although elderly patients often lose some sensitivity at the toes, the various causes of polyneuropathy or dorsal column damage should be considered if the sensory loss is out of proportion for age. The vestibular system contributes to balance and spatial orientation. The most common disorders of the vestibular system are vesibular neuritis, a related condition – labyrinthitis, and Benign Paroxysmal Positional Vertigo (BPPV). The cerebellum contributes to coordination, precision and accurate timing of movements. It receives input from sensory systems and from other parts of the brain and spinal cord, and integrates these inputs to fine tune motor activity. Cerebeullum pathology causes disorders in fine movement, equilibrium, posture, and motor learning. Patients need adequate muscle strength to stay upright. Weakness due to myopahty, neuropathy, or any UMN or LMN pathology can affect posture. Extrapyramidal tracts are chiefly found in the reticular formation of the pons and medullam, and are distinguished from the tracts of the motor cortex that reach their targets by traveling through the "pyramids" of the medulla. Parkinson’s disease is an extrapyramidal disorder which causes delayed postural corrections when the patient loses balance. Control of BP Blood pressure = the pressure exerted by circulating blood upon the walls of blood vessels The blood pressure is determined by the rate of blood flow produced by the heart (cardiac output), and the resistance of the blood vessels to blood flow. This resistance is produced mainly in the arterioles and is known as the systemic vascular resistance (SVR) or the peripheral vascular resistance (PVR). Blood pressure = cardiac output x SVR Physiological mechanisms to maintain a normal BP are: 1) The autonomic nervous system is the most rapidly responding regulator of blood pressure and receives continuous information from the baroreceptors (pressure sensitive nerve endings) situated in the carotid sinus and the aortic arch. This information is relayed to the brainstem to the vasomotor centre (VMC). A decrease in blood pressure causes activation of the sympathetic nervous system resulting in increased contractility of the heart (beta receptors) and vasoconstriction of both the arterial and venous side of the circulation (alpha receptors). 2) The Capillary fluid shift mechanism refers to the exchange of fluid that occurs across the capillary membrane between the blood and the interstitial fluid. This fluid movement is controlled by the capillary blood pressure, the interstitial fluid pressure and the colloid osmotic pressure of the plasma. Low blood pressure results in fluid moving from the interstitial space into the circulation helping to restore blood volume and blood pressure. 3) Hormonal mechanisms exist both for lowering and raising blood pressure. They act in various ways including vasoconstriction, vasodilation and alteration of blood volume. The principal hormones raising blood pressure are: (a) Adrenaline and noradrenaline secreted from the adrenal medulla in response to sympathetic nervous system stimulation. They increase cardiac output and cause vasoconstriction and act very rapidly. (b) Renin and angiotensin production is increased in the kidney when stimulated by hypotension. Angiotensin is converted in the lung to Angiotensin II, which is a potent vasoconstrictor. In addition these hormones stimulate the production of aldosterone from the adrenal cortex which decreases urinary fluid and electrolyte loss from the body. This system is responsible for the long term maintenance of blood pressure but is also activated very rapidly in the presence of hypotension. 4) The kidneys also regulate the blood pressure by increasing or decreasing the blood volume; they are the most important organs for the long term control of blood pressure. Pathophysiology of heart and its conducting system. Basics of cardiac pacing. Permanent pacemakers are implantable devices designed to alter the cardiac rhythm during pathologic states. They are usually placed in the anterior chest wall, and have one or two wire leads which enter the subclavian vein, travel to the right side of the heart, and are implanted into the wall of the right atrium and/or right ventricle. Newer biventricular pacemakers, used in advanced heart failure, also have a lead to the left ventricle via the coronary sinus. Each lead may serve to either pace a specific chamber, sense the intrinsic electrical activity of a specific chamber, or both. A system of codes has been developed to easily describe each possible combination: 1 2 3 4 (optional) Chambers Paced Chambers Sensed Response to Sensed Stimulus Rate Modulation? O (none) O O O (non rate-responsive) A (atrium) A T (triggered) R (rate-responsive) V (ventricle) V I (inhibited) D (both atrium D D (both triggered and ventricle) and inhibited) A fifth position is sometimes used to specify the absence or location of multisite pacing (i.e. biventricular pacing for patients with end-stage left heart failure). The term triggered means that an output pulse is created in response to a sensed event, whereas inhibited means that the output pulse is blocked in response to a sensed stimulus and that the pacemaker then cycles for one or more timing cycles. Pacemakers capable of rate modulation can increase their pacing rate in response to vibration, minute ventilation, temperature, oxygen saturation, or other stimuli, independent of the heart’s intrinsic activity. Most modern pacemakers are capable of mode switching in response to sustained atrial arrhythmias to prevent extreme ventricular response rates (i.e. DDD VVI in the setting of atrial flutter). Understand pathology of index condition. Mechanisms and effects of syncope Cardiovascular causes of syncope (e.g. arrhythmias, aortic stenosis, vasovagal). Postural hypotension (e.g. drugs, autonomic neuropathy). Syncope is a sudden, brief loss of consciousness (LOC) with loss of postural tone followed by spontaneous revival. The patient is motionless and limp and usually has cool extremities, a weak pulse and shallow breathing. Near syncope is light-headedness and a sense of an impending faint without LOC. Fainting – a reflex: • Afferent limb – Various: Pain, emotion, smell, etc. – Integration by deep brain centres – Project to Medulla oblongata and centres in the floor of the fourth ventricle especiallu nucleus of the Xth cranial nerve (Vagus) which become over active. • Efferent limb Vagus • Vagus causes sweating, fall in HR and venous pooling (especially splanchnic) – Result very low CO • Over flow of neural activity in brain to other regulatory centres especially emetic centre – causing nausea • • Collapse – CO insufficient for cerebral perfusion Restoration of consciousness (if allowed to become supine) – Supine posture allows massive increase in VR (especially if legs put in air) – Massive release of adrenaline causes rise in HR and increase in contractility Normal CV reflexes on standing: • Blood pools in limbs • Baroreceptors sense fall in volume and pulse pressure and cause: – Rise in HR – Peripheral vasoconstriction (arteriolar and venous splanchnic and peripheral) – Closure of pre capillary sphincters in limbs CAUSES OF SYNCOPE Most syncope results from insufficient cerebral blood flow. Some cases involve adequate flow but insufficient substrate (O2, glucose or both) – in practice: hypoxia rarely develops acutely to cause syncope (except in diving / plane accidents), and hypoglycaemia usually gives warning symptoms (except in patients taking β-blockers). Insufficient cerebral blood flow 5) Structural cardio-pulmonary conditions - cardiac output Exercise, vasodilation and hypovolaemia exacerbate +/- chest pain, palpitations Occurs in any position (i.e. supine/standing) Onset and recovery is prompt Obstruction of outflow e.g. aortic / mitral stenosis, tetralogy of Fallot Systolic / diastolic dysfunction e.g. ischaemia + heart failure / hypertrophic cardiomyopathy, restrictive myopathy, myocardial rupture, MI Cardiac tumours e.g. atrial myxoma Pericardial tamponade / constriction Pulmonary emobilism / pulmonary hypertension / amniotic fluid embolism / air embolism 6) Arrhythmias Occurs in any position (i.e. supine/standing) Onset and recovery is prompt More common if patient taking drugs, especially antiarrhythmics More common if patient has structural heart disease; A systolic click followed by a blowing systolic murmur that moves closer to the 1st heart sound on standing suggests mitral valve prolapse (suggesting the cause is an arrhythmia). Tachyarrhythmias: too fast to allow adequate ventricular filling (e.g. >150 – 180bpm) Bradyarrhythmias: too slow to provide adequate output (e.g. <30 – 35bpm) – due to sick sinus syndrome, high-grade atrioventricular block, drugs. Sinus node dysfunction (incl. brady/tachy) Atrioventricular conduction disorders Paroxysmal supraventricular and ventricular tachycardias Inherited syndromes (e.g. QT syndromes, Brugada syndrome) Induced by drugs/ implanted device malfunction (pacemaker, ICD) 7) Neurally-mediated reflex syncopal syndromes Warning symptoms e.g. dizziness, nausea, sweating Recovery prompt but not immediate (5-15 mins) Precipitant usually apparent Vaso-vagal / situational faints do not occur in the supine position Vaso-vagal faint Strong emotion e.g. pain, fear, sight of blood Situational faint GI stimulation e.g. swallowing, defecation Increased intrathroacic pressure e.g. tension pneumothorax / cough / sneeze / straining to urinate or defecate / valsalva manoeuvre Carotid sinus pressure/hypersensitivity (baroreceptors at the common carotid artery bifurcation) Glossopharyngeal and trigeminal neuralgial Anaphylaxis 4) Orthostatic hypotension – failure of sinus tachycardia and/or vasoconstriction (autonomic nervous system) to compensate for decrease in venous return on standing Symptoms develop within several minutes of assuming upright position Drop in BP with standing during examination Orthostatic syncope does not occur in the supine position Drugs and alcohol Autonomic dysfunction Anaemia Hypovolaemia Deconditioning due to long-term bed rest Addison’s disease (adrenal insuffiency) Micturition syncope - Occurs in men. Plexus around the bladder is constricted if bladder full. When bladder empties, the venous plexus fills via blood from legs, this decreases venous return 5) Cerebrovascular – CVAs/TIAs rarely cause syncope because most of them do not involve the centrencephalic structures that must be affected to produce LOC. Except, rarely: ‘Steal’ syndromes can cause syncope when a blood vessel has to supply both part of the brain and an arm Basilar artery TIA/CVA Migraine Other Pregnancy Prolonged standing Hyperventilation Hypoglycaemia Features that suggest a non-syncopal attack - Confusion after attack for >5 minutes (seizure) Prolonged (>15 seconds) tonic-clonic movements starting at the onset of the attack (seizure) Frequent attacks with somatic complaints, no organic heart disease, responsive or partially responsive during attacks (psychiatric) Associated with vertigo, dysarthria, diplopia (TIA) Postural hypotension (e.g. drugs, autonomic neuropathy). Syncope that occurs most often when assuming an upright position (particularly in elderly patients after prolonged bed rest or in patients taking drugs in certain classes) suggests orthostatic syncope. Syncope that occurs after standing for long periods without moving is usually due to venous pooling. Factors include rigid, noncompliant arteries, reduced skeletal muscle pumping of venous return due to physical inactivity, and degeneration of the sinoatrial node and conduction system due to progressive structural heart disease. Some disorders that affect BP regulation: Anemia Arrhythmias Cardioinhibitory carotid sinus hypersensitivity COPD Dehydration Infections (eg, pneumonia, sepsis) Metabolic disorders (eg, thyroid disorders, hypoglycemia, hyperglycemia with hyperosmolar dehydration) Neurocardiogenic inhibition after micturition Postprandial hypotension Valvular heart disorders Some drugs that increase orthostatic hypotension: Most antihypertensives (rarely β-blockers) Antipsychotics (mainly phenothiazines) Doxorubicin Levodopa Loop diuretics Nitrates (with or without a phosphodiesterase inhibitor for erectile dysfunction) Quinidine Tricyclic antidepressants Vincristine