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Chapter 16 Respiratory Emergencies National EMS Education Standard Competencies Medicine Integrates assessment findings with principles of epidemiology and pathophysiology to formulate a field impression and implement a comprehensive treatment/disposition plan for a patient with a medical complaint. National EMS Education Standard Competencies Respiratory Anatomy, signs, symptoms, and management of respiratory emergencies including those that affect the – Upper airway – Lower airway National EMS Education Standard Competencies Respiratory (cont’d) Anatomy, physiology, pathophysiology, assessment, and management of – – – – – Epiglottitis Spontaneous pneumothorax Pulmonary edema Asthma Chronic obstructive pulmonary disease National EMS Education Standard Competencies Respiratory (cont’d) Anatomy, physiology, pathophysiology, assessment, and management of (cont’d) – – – – – Environmental/industrial exposure Toxic gas Pertussis Cystic fibrosis Pulmonary embolism National EMS Education Standard Competencies Respiratory (cont’d) Anatomy, physiology, pathophysiology, assessment, and management of (cont’d) – Pneumonia – Viral respiratory infections – Obstructive/restrictive disease National EMS Education Standard Competencies Respiratory (cont’d) Anatomy, physiology, epidemiology, pathophysiology, psychosocial impact, presentations, prognosis, and management of – Acute upper airway infections – Spontaneous pneumothorax – Obstructive/restrictive lung diseases National EMS Education Standard Competencies Respiratory (cont’d) Anatomy, physiology, epidemiology, pathophysiology, psychosocial impact, presentations, prognosis, and management of (cont’d) – Pulmonary infections – Neoplasm – Pertussis – Cystic fibrosis National EMS Education Standard Competencies Shock and Resuscitation Integrates comprehensive knowledge of causes and pathophysiology into the management of cardiac arrest and pre-arrest states. National EMS Education Standard Competencies Shock and Resuscitation (cont’d) Integrates a comprehensive knowledge of the causes and pathophysiology into the management of shock, respiratory failure, or arrest, with an emphasis on early intervention to prevent arrest. Introduction • Respiratory distress is usually caused by respiratory system problems. Epidemiology • Respiratory distress is one of the most common EMS dispatches. – Asthma and COPD are among the top 10 chronic conditions causing restricted activity. – Pneumonia is one of the most common fatal illnesses in developing countries. Epidemiology • Some respiratory diseases are genetic while others are caused by external factors. – Many respiratory diseases are caused by a combination of factors. Hypoventilation • Carbon dioxide accumulates in the blood when the lungs fail to work properly. – Combines with water to form bicarbonate ions and hydrogen ions • Results in acidosis Hypoventilation • Impaired ventilation is caused by a variety of factors. Hypoventilation • Carbon dioxide level is directly related to pH – Hyperventilating patients usually have respiratory alkalosis. – Hypoventilating patients usually have respiratory acidosis. Hypoventilation • Causes of hypoventilation include: – Conditions that impair lung function • Atelectasis • Pneumonia • Pulmonary edema • Asthma • COPD Hypoventilation • Causes of hypoventilation include (cont’d): – Conditions that impair mechanics of breathing • High cervical fracture • Flail chest • Severe retractions • Air- or blood-filled abdomen • Obesity hypoventilation syndrome Hypoventilation • Causes of hypoventilation include (cont’d): – Conditions that impair neuromuscular apparatus • Head trauma, intracranial infections, brain tumors • Serious spinal cord injury • Guillain-Barre syndrome • Amyotrophic lateral sclerosis (Lou Gehrig disease) • Botulism Hypoventilation • Causes of hypoventilation include (cont’d): – Conditions that reduce respiratory drive • Intoxication • Head injury • Hypoxic drive • Asphyxia Hypoventilation • The ultimate manifestation is respiratory arrest followed by cardiac arrest. • Initiate aggressive treatment to assist the patient’s respiratory efforts. Hyperventilation • Occurs when people breathe in excess by increasing rate and/or depth of respiration – Releases more carbon dioxide than normal • Results in alkalosis – Triggered by emotional distress or panic: hysterical hyperventilation or hyperventilation syndrome Hyperventilation • Causes numbness in hands, feet, and mouth • Ultimately leads to carpopedal spasm – Symptoms often cause more hyperventilation. Hyperventilation • Having patient rebreathe carbon dioxide can be dangerous. – Patients quickly exhaust the oxygen in the gas they are breathing. – Hyperventilation in a patient with acidosis may be the body’s attempt to raise the pH level. Hyperventilation • Treatment may include: – Sedation – Psychological support: • Breathing with the patient • Having the patient count to two between breaths • Distraction techniques • Having the patient sing a song Anatomy and Physiology • Respiratory system structures look like an inverted tree. Structures of the Upper Airway • Nostrils and nose – Air enters through the nostrils. • Lined with nasal hairs – Quiet breathing allows air to flow through the nose. Structures of the Upper Airway • Turbinates – Highly vascular ridges covered with mucus membrane • Traps particulates • Warm and humidify air as it passes – Many blood vessels—swell and bleed easily Structures of the Upper Airway Structures of the Upper Airway • Mouth and oropharynx – Contain blood vessels and mucous membrane – Edema can be extreme. – Ask patient if their tongue feels thick. – Monitor speech. © E. M. Singletary, M.D. Used with permission. Structures of the Upper Airway • Hypopharynx – Where the oropharynx and nasopharynx meet – Gag reflex is profound. • Triggering may cause vagal bradycardia, vomiting, and increased intracranial pressure. • May make airway device use difficult Structures of the Upper Airway • Larynx and glottis – Dividing line between upper and lower airway – Thyroid cartilage: external landmark Structures of the Upper Airway • Larynx and glottis (cont’d) – Several cartilages support the vocal cords. • Arytenoid cartilages: found at the distal end of each vocal cord • Piriform fossae: pockets of tissue found on either side of the glottis • Cricoid cartilage: palpated just below the thyroid cartilage Structures of the Upper Airway • Larynx and glottis (cont’d) – Cricothyroid membrane: small space between the thyroid and cricoid cartilage • Does not contain many blood vessels • Covered only by skin • Potential site for cricothyrotomy Structures of the Upper Airway • Larynx and glottis (cont’d) – Laryngeal swelling or trauma can create lifethreatening airway obstruction. Structures of the Lower Airway • Tracheobronchial tree – Trachea— trunk of tree • Carries air to the lungs • Extends from the larynx to the mainstem bronchi Structures of the Lower Airway • Tracheobronchial tree (cont’d) – Mainstem bronchi branch into: • Lobar bronchi • Segmental bronchi • Subsegmental bronchi • Bronchioles Structures of the Lower Airway • Bronchi and bronchioles are lined with cilia. Inset photo: © Dr. Kessel & Dr. Kardon/Tissue & Organs/Visuals Unlimited. © Dr. Kessel & Dr. Kardon/Tissue & Organs/Visuals Unlimited Inset photo: © Dr. Kessel & Dr. Kardon/Tissue & Organs/Visuals Unlimited. Structures of the Lower Airway • Bronchioles – Significant amount of gas exchange Structures of the Lower Airway • Bronchioles (cont’d) – Goblet cells produce mucus blanketing. • Gel layer • Sol layer – Smooth muscle surrounds the airway. • Bronchoconstriction: smooth muscle narrows the airway. Structures of the Lower Airway • Alveoli – Gas exchange interface • Deoxygenated blood releases carbon dioxide and is resupplied with oxygen. – Made up of two types of cells: • Type I: almost empty • Type II: can make new type I cells Structures of the Lower Airway • Alveoli (cont’d) – Function best when kept partially inflated – Collapsed, fluidfilled, or pus-filled alveoli do not play a part in gas exchange. Structures of the Lower Airway • Alveoli (cont’d) – Pulmonary capillary bed • Pulmonary circulation starts at the right ventricle. • Pulmonary capillaries are narrow. – Patients with chronic lung disease and chronic hypoxia often have thick blood (polycythemia). • Strains right side of heart, leads to cor pulmonale Structures of the Lower Airway Structures of the Lower Airway • Alveoli (cont’d) – Interstitial space • Network of gaps between alveoli and capillaries • Filled with interstitial fluid – Conducting airways distributes inspired gas, which does not participate in ventilation • Wasted ventilation: dead space (1 mL per pound of ideal body weight) Structures of the Lower Airway • Chest wall – Forms a bellows system with chest muscles – The diaphragm is the primary muscle. • Causes pressure changes to move air in and out – Ribs maintain pressure. – Pleural membranes allow organs to move smoothly. Structures of the Lower Airway • Chest wall (cont’d) – Trauma and diseases of the bones and muscles can significantly impair air movement. • Causes restrictive lung diseases Structures of the Lower Airway • Mediastinum: middle of the chest – Consists of: • Heart • Large blood vessels • The large conducting airways • Other organs Functions of the Respiratory System • Respiration—process of oxygen taken into body and distributed to the cells for energy – Carbon dioxide is returned to the lungs by the circulatory system and exhaled. Functions of the Respiratory System • Ventilation – Movement of air in and out of the lungs – Best measured by the carbon dioxide level • Normal breathing removes enough carbon dioxide to keep acid-base balance. • PACO2 must be 35 to 45 mm Hg for normal ventilation. Functions of the Respiratory System • Diffusion – For oxygen to go from an alveolus to a red blood cell, it must: • Diffuse into the alveolar cell and out the other side. • Diffuse into the capillary wall and out the other side. Functions of the Respiratory System • Diffusion (cont’d) – Some lung diseases make it difficult for oxygen to diffuse into the blood. – Effective diffusion: higher concentration of oxygen in the alveoli than in the bloodstream Functions of the Respiratory System • Perfusion – Circulatory component of respiratory system – Blood must keep flowing through pulmonary vessels. – A large embolus can block blood flow to the lung. Mechanisms of Respiratory Control • Neurologic control – Centered in the medulla – At least four parts of brainstem responsible for unconscious breathing – Stretch receptors cause coughing if taking too deep a breath • Hering-Breuer reflex Mechanisms of Respiratory Control • Neurologic control (cont’d) – Other neurologic control mechanisms: • Phrenic nerve innervates diaphragm. • Thoracic spinal nerves innervate intercostal muscles. Mechanisms of Respiratory Control • Cardiovascular regulation – Lungs closely linked to cardiac function – Heart changes have pulmonary consequences. – Left-sided heart failure progresses faster than right-sided heart failure. Mechanisms of Respiratory Control • Cardiovascular regulation (cont’d) – Mild hypoxia causes increase in heart rate – Severe hypoxia causes bradycardia. – Uncorrected hypoxic insults may trigger lethal cardiac arrhythmia. Mechanisms of Respiratory Control • Cardiovascular regulation (cont’d) – Various forms of heart failure from: • Fluid balance changes • Right-sided heart pumping pressure • Left-sided heart pumping pressure Mechanisms of Respiratory Control • Muscular control – Body takes in air by negative pressure – Air through mouth and nose, over turbinates, around epiglottis and glottis Mechanisms of Respiratory Control • Muscular control (cont’d) – Thorax: airtight box with diaphragm at bottom and trachea at top – Diaphragm flattens during quiet breathing. • Air is sucked in to fill the increasing space. Mechanisms of Respiratory Control • Muscular control (cont’d) – Minute ventilation can be increased by: • Deep breathing • Rapid breathing – Accessory muscles cause dramatic pressure changes when greater amounts of air must be moved. Mechanisms of Respiratory Control • Muscular control (cont’d) – Traumatic opening in thorax provides route for air to be sucked in • Sucking chest wound – Exhalation is a passive process. Mechanisms of Respiratory Control • Renal status – Kidneys play a part in controlling: • Fluid balance • Acid-base balance • Blood pressure – Factor into pulmonary mechanics and oxygen delivery to body tissues Assessment of a Patient with Dyspnea • Respiratory assessment includes much more than listening to the patient’s lungs. – Many respiratory ailments are life threatening. – Respiratory assessment should be done early. Scene Size-Up • Observe standard precautions. • Use proper PPE. • Evaluate scene safety for: – – – – Decreased oxygen concentrations Carbon monoxide Irritant gasses Highly contagious respiratory illness Scene Size-Up • Respiratory diseases can impair: – – – – Ventilation Diffusion Perfusion Combination of all three • Rapid-onset dyspnea may be caused by: – – – – Acute bronchospasm Anaphylaxis Pulmonary embolism Pneumothorax Primary Assessment • Form a general impression. – Body type may be associated with condition • Emphysema: barrel chest, muscle wasting, pursedlip breathing, tachypneic • Chronic bronchitis: sedentary, obese, sleep upright, spit-up secretions Primary Assessment • Observe condition during typical exertion. – Tachycardia, diaphoresis, and pallor can be triggered by: • Increased work of breathing • Anxiety • Hypoxia Primary Assessment • Position and degree of distress – Prefer sitting positions, such as tripod position – Lying flat may be a sign of sudden deterioration. – Ominous sign: head bobbing Primary Assessment • Breathing alterations – Can be complex and involve: • Problems with the airway branches • Difficulties at the alveolar level • Problems with the muscles and nerves • Problems with the rigid structure of the thorax • Increased work of breathing – Patients using accessory muscles to breathe are in danger of tiring out. • Infants and small children are in danger of collapse of flexible sternum cartilage. Courtesy of Health Resources and Services Administration, Maternal and Child Health Bureau, Emergency Medical Services for Children Program. Primary Assessment Primary Assessment • Increased work of breathing (cont’d) – Profound intrathoracic pressure changes can cause peripheral pulses to weaken or disappear. Primary Assessment • Altered rate and depth of respiration – Patient with adequate rate but low volume will have inadequate minute volume. • Respiratory rate × tidal volume = minute volume – Monitor trends in respiratory rates. – Note inspiratory-to-expiratory (I/E) ratio. Primary Assessment • Abnormal breath sounds – Auscultate lungs systematically. – Some conditions are gravitydependent and others diffuse throughout the lungs. Primary Assessment • Abnormal breath sounds (cont’d) – Breath sounds are created by airflow in the large airways. Primary Assessment Primary Assessment • Abnormal breath sounds (cont’d) – Some conditions cause normal breath sounds to be heard in abnormal places. – Sounds move better through fluid than in air. – Quality of sounds is dependent on the amount of tissue between stethoscope and structures. Primary Assessment • Abnormal breath sounds (cont’d) – Continuous: wheezes – Discontinuous: crackles • Rales • Rhonchi • Pleural friction rub Primary Assessment • Abnormal breath sounds (cont’d) – Audible sounds include: • Stridor—upper airway obstruction • Grunting—lower airway obstruction • Death rattle—patients can’t clear secretions – The most ominous sounds are no sounds. Primary Assessment • Abnormal breath sounds (cont’d) – Noisy breathing • Snoring: Partial obstruction of the upper airway by the tongue • Gurgling: Fluid in the upper airway • Stridor: Narrowing from swelling – Quiet breathing • Hyperventilation • Shock Primary Assessment • Sputum – Has color or amount changed from normal? Primary Assessment • Abnormal breathing patterns – May indicate neurological insults • Brain trauma or any disturbance may depress respiratory control centers in the medulla. • Brain injuries may damage or deprive blood flow. Primary Assessment Primary Assessment • Most respiratory centers are in and around the brainstem. Primary Assessment • Circulation – Assess skin color. • Note generalized cyanosis. • Pink in healthy patients © Logical Images/Custom Medical Stock Photo Primary Assessment • Circulation (cont’d) – Cyanosis • Healthy hemoglobin levels: 12 to 14 g/dL • Cyanosis begins at about 5 g/dL desaturation – Chocolate brown skin • May occur from high levels of methemoglobin – Pale skin • Caused by a blood flow reduction to small vessels Primary Assessment • Circulation (cont’d) – Check for dehydration: • Dry, cracked lips • Dry, furrowed tongue • Dry, sunken eyes Primary Assessment • Transport decisions – Usually transported to closest hospital • If available, consider pediatric centers. • If renal failure, consider a facility that can provide emergency dialysis. • If multiple emergency departments are available, consider taking patient to his or her preferred facility. History Taking • Investigate chief complaint – Increased cough – Change in amount or color of sputum – Fever – Wheezing – Dyspnea – Chest pain History Taking • Patient may know exact problem. – Asthma with fever – Failure of a metered-dose inhaler – Travel-related problems – – – – Dyspnea triggers Seasonal issues Noncompliance with therapy Failure of technology or running out of medicine History Taking • SAMPLE history – Signs and symptoms – Allergies – Medications • Antihistamines • Antitussives • Bronchodilators • Diuretics • Expectorants – Pertinent past medical history – Last oral intake – Events preceding the onset of the complaint Secondary Assessment • Neurologic assessment – Note level of consciousness. • Decline in PaO2: restlessness, confusion, and combative behavior • Increase in PaCO2: sedative effects – If lungs are not functioning correctly, oxygen may not be delivered and carbon dioxide may not be removed. Secondary Assessment • Neck exam – Jugular venous distention • Common with asthma or COPD • Rough measure of pressure in right atrium © ejwhite/ShutterStock, Inc. Secondary Assessment • Neck exam (cont’d) – Note trachea for deviation. Courtesy of Stuart Mirvis, MD • Sign of tension pneumothorax Secondary Assessment • Chest and abdominal exam – Pressing on the liver when in respiratory distress and semi-Fowler’s position will cause the jugular veins to bulge. • Hepatojugular reflex – Feel for vibrations in the chest as the patient breathes. Secondary Assessment • Examination of the extremities – – – – – – Edema Cyanosis. Pulse Pulsus paradoxus Temperature Distal clubbing © Jones & Bartlett Learning. Photographed by Kimberly Potvin. © Mediscan/Visuals Unlimited Secondary Assessment • Vital signs – Patients under stress can be expected to have tachycardia and hypertension. – Ominous signs: • Bradycardia • Hypotension • Falling respiratory rates Secondary Assessment • Stethoscope – Diaphragm is for high-pitched sounds. – Bell is for low-pitched sounds. – The longer the tubing, the more extraneous noise that is heard. Secondary Assessment • Pulse oximeter – Noninvasive way to measure the percentage of hemoglobin with oxygen attached – Oxygen saturation over 95% = normal Secondary Assessment • Pulse oximeter (cont’d) – Oxygen saturation should match patient’s palpated heart rate. – If hemoglobin level is low, the pulse oximetry result will be high. – Does not differentiate between oxygen or carbon monoxide molecules Secondary Assessment • Pulse oximeter (cont’d) – Oxyhemoglobin dissociation curve • Relationship between oxygen saturation and amount of oxygen dissolved in the plasma (PaO2). Secondary Assessment • End-tidal carbon dioxide detector – Capnometry: ETCO2 monitoring – Wave capnography: ETCO2 monitoring that measures carbon dioxide and plots a waveform graph Secondary Assessment • End-tidal carbon dioxide detector (cont’d) – Colorimetric detector indicates whether carbon dioxide is present in reasonable amounts Courtesy of Marianne Gausche-Hill, MD, FACEP, FAAP Secondary Assessment • End-tidal carbon dioxide detector (cont’d) – Special sensor can measure the percentage of carbon dioxide and display a waveform • Waveform capnography LIFEPAK® defibrillator/monitor. Courtesy of Medtronic. Secondary Assessment • End-tidal carbon dioxide detector (cont’d) – ETCO2 of less than 10 torr: less-than-optimal CPR compressions – Sudden increase in ETCO2: spontaneous circulation return Secondary Assessment • Peak expiratory flow – Maximum rate at which a patient can expel air – Normal values: 350 to 700 L/min • Variable by age, sex, and height – Inadequate level: 150 L/min Reassessment • Interventions – Oxygen (keep saturations above 93%) – IV line – Psychological support Reassessment • Interventions (cont’d) – Sympathetic: speeds heart rate – Parasympathetic: slows heart rate • Anticholinergic medications block the parasympathetic response. Reassessment • Interventions (cont’d) – Ipratropium is used today. • Combination of albuterol and ipratropium – Anticholinergics are a central component to manage COPD. Reassessment • Aerosol therapy – Nebulizers deliver fine mist of liquid medication. • Need gas flow of at least 6 L/min to keep particles optimal size. Reassessment • Aerosol therapy (cont’d) – A nebulizer can be attached to: • A mouthpiece • Face mask • Tracheostomy collar • Can also be held in front of the patient’s face (blowby technique) Reassessment • Aerosol therapy (cont’d) – Can disperse other drugs through aerosols: • Corticosteroids • Anesthetic agents • Antitussives • Mucolytics Reassessment • Metered-dose inhalers – Small, easy to carry and use, convenient – Ambulance metered-dose inhalers should have spacers. Reassessment • Metered dose inhalers (cont’d) – To avoid common errors: • Inhale deeply at discharge. • Suck medication out of the bottom. • Flow should be smooth and low-pressure. • Inhale deeply; hold breath for a few seconds. • Make sure the inhaler contains medication. • Keep the spacer and canister holder clean. • After using corticosteroid inhaler, rinse mouth. Reassessment • Failure of a metered-dose inhaler – Must be properly used. • Contraindicated if patient cannot move enough air into the lungs. • Patient may not realize the inhaler is empty. • Patient may inhale at the wrong time. Reassessment • Dry powder inhalers – May be dispensed by means of a plastic disk • Patient inhales deeply to suck out the powder. – Other devices require the patient to insert a capsule of powdered medication. Reassessment • Communication and documentation – Contact medical control: • To report change in level of consciousness or increased breathing difficulty • Before assisting with prescribed medication – Document changes, times occurred, orders given by medical control. Emergency Medical Care • Goal is to: – Provide supportive care. – Administer supplemental oxygen. – Provide monitoring and transport. Ensure Adequate Airway • Remove items from mouth. • Suction if necessary. • Keep airway in optimal position. Decrease the Work of Breathing • Muscles work harder during respiratory distress. – Use substantial energy to compensate for respiratory distress. • Requires more oxygen and ventilation • May fatigue to point of decompensation Decrease the Work of Breathing • To decrease the work of breathing: – Help the patient sit up. – Remove restrictive clothing. – Do not make the patient walk. – Relieve gastric distention. – Do not bind the chest or have the patient lie on the unaffected lung. Provide Supplemental Oxygen • Administer in effective concentrations. – Reassess, then adjust as needed. – Pulse oximetry is a good guide to oxygenation. • Concentrations higher than 50% should be used only with hypoxia that does not respond to lower concentrations. Administer a Bronchodilator • Many can benefit from bronchodilation. – Those without bronchospasms will benefit only slightly. – Bronchodilators are ineffective in cases of: • Pneumonia • Pulmonary edema • Heart disease Administer a Bronchodilator • Fast-acting bronchodilators – Most stimulate beta-2 receptors in lung • Provide almost instant relief – Albuterol is the most common beta-2 agonist. Administer a Bronchodilator • Slow-acting bronchodilators – Do not provide immediate symptom relief – Daily dose reduces frequency/severity of attacks – Common medications include: • Salmeterol • Cromolyn Administer a Bronchodilator • Methylxanthines – Declining use because of adverse effects • Overdose can cause cardiac dysrhythmias and hypotension. • Carefully monitor level in bloodstream. Administer a Bronchodilator • Electrolytes – Magnesium may have a role in bronchodilation. – Some physicians use them as a last-ditch effort before intubation. Administer a Bronchodilator • Corticosteroids – Reduce bronchial swelling – Adverse effects: • Cushing syndrome • Rapid change in blood glucose levels • Blunts the immune system – Avoid long-term use. Administer a Bronchodilator • Inhaled corticosteroids – Less adverse effects; becoming standard • Intravenous corticosteroids – Methylprednisolone and hydrocortisone: used for acute asthma attacks or COPD Administer a Vasodilator • Sequester more fluid in venous circulation and decrease preload – Nitrates can be used if patient: • Has adequate blood pressure • Does not take a phosphodiesterase inhibitor. – Morphine sulfate is not likely to increase venous capacity. Restore Fluid Balance • Common to give fluid bolus to dehydrated, younger patients. – Elderly patients or patients with cardiac dysfunction could wind up with pulmonary edema. • Assess breath sounds before and after. Administer a Diuretic • Helps reduce blood pressure and maintain fluid balance in patients with heart failure • Helps remove excess fluid from circulation, keeping it out of the lungs of patients with pulmonary edema. Administer a Diuretic • Many diuretics cause potassium loss. – May lead to cardiac dysrhythmias and chronic muscle cramping • Do not give diuretics to patients with pneumonia or dehydration. Support or Assist Ventilation • Breathing may need more aggressive support if the patient becomes fatigued. – CPAP and BiPAP may preclude intubation. – May simply require bag-mask ventilation Support or Assist Ventilation • Continuous positive airway pressure – Used to treat: • Obstructive sleep apnea • Respiratory failure – Patients with obstructive sleep apnea wear a CPAP unit to maintain airway while they sleep. Support or Assist Ventilation • CPAP (cont’d) – CPAP therapy may be delivered through a mask. • Air is forced into the upper airway. • Positive pressure is created in the chest. Support or Assist Ventilation • CPAP (cont’d) – Pressure that is too high may cause: – New guidelines emphasize: • Tension pneumothorax • Lower ventilation rates • Subcutaneous air • Block venous returns • Smaller volumes • Lower pressures Support or Assist Ventilation • CPAP (cont’d) – Ensure a seal. – If a patient is unwilling to use it, do not fight it. – Success is related to respiratory rate after application Courtesy of Respironics, Inc., Murrysville, PA. All rights reserved. Support or Assist Ventilation • Bi-level positive airway pressure (BiPAP) – One pressure on inspiration and a different pressure during exhalation • More like normal breathing • More complex and expensive Support or Assist Ventilation • Automated transport ventilators – Flow restricted oxygen-powered ventilation • Deliver a particular oxygen volume at a set rate. • Good for patients in cardiac or respiratory arrest • Not intended to be used without direct observation Courtesy of Airon Corporation (www.AironUSA.com) Intubate the Patient • Last option for patients with severe asthma • Ventilate patients before cardiac arrest. • Patients who are severely intoxicated or have had a stroke may have no gag reflex. Intubate the Patient • With diabetes or overdose, an ampule of 50% dextrose or naloxone may change the need for intubation – Use bag-mask ventilation for a few minutes to monitor effects. Inject a Beta-Adrenergic Receptor Agonist Subcutaneously • Use if inhalation techniques are ineffective. – May cause more tachycardia and hypertension – Be careful using in elderly patients. Instill Medication Directly Through an Endotracheal Tube • Option if prompt vascular access is delayed • Epinephrine dose is 2 to 2.5 times the usual • Newer devices mist drug into ET tube – Can be used without interrupting CPR Anatomic Obstruction • Pathophysiology – The tongue is the most common cause of airway obstruction if patient is semiconscious or unconscious. Anatomic Obstruction • Assessment: – Risks include: • Decreased level of consciousness – Audible signs include: • Sonorous respirations • Gurgling • Squeaking and bubbling Anatomic Obstruction • Management – Obstructive sleep apnea may be caused by excess soft tissue in airway • Can be manually displaced • Place patient in the recovery position Inflammation Caused by Infection • Pathophysiology – Infections can cause upper airway swelling. • Can lead to laryngotracheobronchitis • Common cause of croup – Stridor – Hoarseness – Barking cough Inflammation Caused by Infection • Pathophysiology (cont’d) – Poiseuille’s law: as the diameter of a tube decreases, resistance to flow increases. Inflammation Caused by Infection • Assessment – Croup and tonsillitis are common, but other conditions are rare. – Avoid manipulating the airway. Inflammation Caused by Infection Inflammation Caused by Infection • Management – Airway may be entirely obscured. • Laryngoscopy may worsen swelling – Have partner press on the chest while you check for a bubble stream. • If effort fails, cricothyrotomy may be necessary. Aspiration • Inhalation of anything other than breathable gases • Patients at risk: – Tube-fed patients placed supine after large meal – Geriatric patients with impaired swallowing – Unresponsive patients Aspiration • Pathophysiology – Aspiration of stomach contents: high mortality – Aspiration of foreign bodies may occur. • Chronic aspiration of food is a common cause of pneumonia in older patients. Aspiration • Assessment – Determine scenario of sudden onset dyspnea • Immediately after eating? • Gastric feeding tube? Aspiration • Management – Avoid gastric distention when ventilating. • Use nasogastric tube to decompress stomach. – Monitor ability to protect airway; use advanced airway when needed. – Treat with suction and airway control. Obstructive Lower Airway Diseases • Diseases that cause airflow obstruction to the lungs: – Emphysema and chronic bronchitis (COPD) – Asthma Obstructive Lower Airway Diseases • Physical findings: – Pursed lip breathing – Increased I/E ratio – Abdominal muscle use – Jugular venous distension Asthma • Pathophysiology – Increased tracheal and bronchial reactivity • Causes widespread, reversible airway narrowing (bronchospasm) © Scott Rothstein/ShutterStock, Inc. Asthma • Pathophysiology (cont’d) – Patients with potentially fatal asthma often have severely compromised ventilation all the time. • Acute bronchospasm or infection presents risk • Death rates are increasing in the United States. Asthma • Pathophysiology (cont’d) – Status asthmaticus: severe, prolonged attack that does not stop with conventional treatment • Struggling to move air through obstructed airways • Prominent use of accessory muscles • Hyperinflated chest • Inaudible breath sounds • Exhausted, severely acidotic, and dehydrated Asthma • Assessment – Known as reactive airway disease because bronchospasms are caused by triggers – Also caused by: • Airway edema • Inflammation • Increased mucus production Asthma • Assessment (cont’d) – Bronchospasm • Constricting muscle surrounding bronchi • Wheezing: air forced through constricted airways • Primary treatment: nebulized bronchodilator medication Asthma Asthma • Assessment (cont’d) – Bronchial edema • Swelling of the bronchi and bronchioles • Bronchodilator medications do not work. – Increased mucus production • Thick secretions contribute to air trapping. • Dehydration makes secretions thicker. Asthma • Management – Bronchospasm: aerosol bronchodilators – Bronchial edema: corticosteroids – Excessive mucus secretion: improve hydration, mucolytics Asthma • Management (cont’d) – Transport considerations • Infection or continuous exposure to a trigger: consider removing patient. • No improvement in peak flow: consider corticosteroids. Asthma • Management (cont’d) – Transport considerations • Undernourished or dehydrated: consider IV fluids. • Advanced life support more than a few minutes away: consider transport to nearest ED. Chronic Obstructive Pulmonary Disease • Pathophysiology – Emphysema damages or destroys terminal bronchiole structures. – Chronic bronchitis: sputum production most days of the month for 3 or more months of the year for more than 2 years Chronic Obstructive Pulmonary Disease • Assessment – Emphysema • Barrel chest from chronic lung hyperinflation • Tachypneic • Use muscle mass for energy to breathe Chronic Obstructive Pulmonary Disease • Assessment (cont’d) – Causes of diffuse wheezing: • Left-sided heart failure (cardiac asthma) • Smoke inhalation • Chronic bronchitis • Acute pulmonary embolism – Cause of localized wheezing: obstruction from foreign body or tumor Chronic Obstructive Pulmonary Disease • COPD with pneumonia – Often have lung infection – Check for: • Fever • Change in sputum • Other infection signs • Breath sounds consistent with pneumonia Chronic Obstructive Pulmonary Disease • COPD with right-sided heart failure – Look for: • Peripheral edema • Jugular venous distention with hepatojugular reflux • End inspiratory crackles • Progressive increase in dyspnea • Greater-than-usual fluid intake • Improper use of diuretics Chronic Obstructive Pulmonary Disease • COPD with left-sided heart failure – Can be caused by any abrupt left ventricular dysfunction Chronic Obstructive Pulmonary Disease • Acute exacerbation of COPD – Sudden decompensation with no copathologic conditions – Often from environmental change or inhalation of trigger substances Chronic Obstructive Pulmonary Disease • End-stage chronic COPD – Lungs no longer support oxygenation, ventilation – Difficult to tell whether situation can be resolved – Secure documentation of patient’s wishes. – Follow local protocol or contact medical control. Chronic Obstructive Pulmonary Disease • COPD and trauma – Lessens ability to tolerate trauma – Monitor closely. – Oxygen saturation might be less than 90%. • Achieving a saturation of 98% is unrealistic. Chronic Obstructive Pulmonary Disease • Management – Can help improve immediate distress – Determine what caused the situation to worsen enough for the patient to call for help. – Must understand: • Hypoxic drive • Positive end-expiratory pressure (auto-PEEP) Chronic Obstructive Pulmonary Disease • Hypoxic drive – When breathing stimulus comes from decrease in PaO2 rather than increase in PaCO2 – Affects only a small percentage during endstage of disease process – Must decide whether to administer oxygen Chronic Obstructive Pulmonary Disease • Hypoxic drive (cont’d) – Impossible to tell which patients breathe because of hypoxic drive. – Encourage breathing. – Skin appearance may remain perfused if patient becomes apneic. Chronic Obstructive Pulmonary Disease • Hypoxic drive (cont’d) – Provide artificial ventilation and consider intubation if patient become apneic. – Intubation may mean the patient remains on the ventilator until the end of life. – Oxygen saturation values are less useful in patients with COPD. Chronic Obstructive Pulmonary Disease • Auto-PEEP – Allow complete exhalation before the next breath during ventilation. • Otherwise, pressure in the thorax will continue to rise (auto-PEEP). – If possibility, patients should be ventilated 4 to 6 breaths/min. Pulmonary Infections • Pathophysiology – Infections from: • Bacteria • Viruses • Fungi • Protozoa – Infectious diseases cause: • Swelling of the respiratory tissues • Increase in mucus production • Production of pus Pulmonary Infections • Pathophysiology (cont’d) – Resistance to airflow increases when the airway diameter is narrowed (Poiseuille’s law). – Alveoli can become nonfunctional if filled with pus. Pulmonary Infections • Pathophysiology (cont’d) – At greater risk of pneumonia: • Older people • People with chronic illnesses • People who smoke • Anyone who does not ventilate efficiently • Those with excessive secretions • Those who are immunocompromised Pulmonary Infections • Assessment – Patients usually report: • Several hours to days of weakness • Productive cough • Fever • Chest pains worsened by cough Pulmonary Infections • Assessment (cont’d) – May start abruptly or gradually – During physical examination, patient: • May look grievously ill • May or may not be coughing • May present with crackles • May have increased tactile fremitus and sputum production Pulmonary Infections • Assessment (cont’d) – Pneumonia often occurs in the lung bases. – Patients are often dehydrated. – Supportive care includes: • Oxygenation • Secretion management (suctioning) • Transport to the closest facility Pulmonary Infections • Management – Upper airway infections: aggressive airway management – Lower airway infections: supportive care, transport Atelectasis • Pathophysiology – Disorders of alveoli • Collapse from proximal airway obstruction or external pressure • Fill with pus, blood, or fluid • Smoke or toxin damage Atelectasis • Pathophysiology (cont’d) – Common for some alveoli to collapse • Sighing, coughing, sneezing, and changing positions help open closed alveoli. – When alveoli do not reopen, entire lung segments eventually collapse. – Increases chance of pneumonia Atelectasis • Assessment – The affected area can harbor pathogens that result in pneumonia. • Check if a patient with fever has had recent chest or abdominal surgery. Atelectasis • Management – Postsurgical patients encouraged to: • Get out of bed. • Cough. • Breathe deeply. • Use the incentive spirometer. © T. Bannor/Custom Medical Stock Photo Cancer • Pathophysiology – Lung cancer is one of most common forms of cancer. • Cigarette smoking • Exposure to occupational lung hazards Cancer • Assessment – First presentation is often hemoptysis. – Frequently accompanied by COPD and impaired lung function – Often metastasizes in the lung from other body sites Cancer • Assessment (cont’d) – Other cancers may invade lymph nodes in neck. – Pulmonary complications from radiation and chemotherapy – Treatments may cause pleural effusion. Cancer • Management – Little prehospital treatment for pleural effusions or hemoptysis – Sometimes called for end-of-life issues Toxic Inhalations • Pathophysiology – Damage depends on water solubility of toxic gas. Toxic Inhalations • Assessment – Highly water-soluble gases react with moist mucous membranes. • Causes upper airway swelling and irritation – Less water-soluble gases get deep in lower airway. • More damage over time Toxic Inhalations • Assessment (cont’d) – Moderately water-soluble gases have signs and symptoms between. • Mixing drain cleaner and chlorine bleach may produce an irritant chlorine gas. • Industrial settings often use irritant gas-forming chemicals in higher quantities and concentrations. Toxic Inhalations • Management – Immediate removal from contact with gas – Provide 100% oxygen or assisted ventilation. – If exposure is to slightly water-soluble gases, patients may have acute dyspnea hours later. • Consider transport to closest ED for observation. Pulmonary Edema • Pathophysiology – Fluid buildup in lungs occurring when blood plasma fluid enters lung parenchyma – Classifications: • High pressure (cardiogenic) • High permeability (noncardiogenic) Pulmonary Edema • Assessment – By time crackles can be heard, fluid has: • Leaked out of capillaries • Increased diffusion space between capillaries and alveoli • Swollen alveolar walls • Begun to seep into alveoli Pulmonary Edema • Assessment (cont’d) – Listen to lower lobes through the back. – Crackles heard higher in the lungs as condition worsens – In severe cases, watery sputum, often with a pink tinged, will be coughed up. Acute Respiratory Distress Syndrome • Pathophysiology – Seldom seen in field – Caused by diffuse damage to alveoli from: • Shock • Aspiration of gastric contents • Pulmonary edema • Hypoxic event Acute Respiratory Distress Syndrome • Assessment – Document oxygen saturation, breath sounds, and any sudden changes. – Monitor ventilation pressures. Pneumothorax • Pathophysiology – Air collects between visceral and parietal pleura. – Weak spots (blebs) can predispose a person. Pneumothorax • Assessment – Patients may have: • Sharp pain after coughing • Increasing dyspnea in subsequent minutes or hours Pneumothorax • Management – Most will not require acute intervention. – They should receive oxygen and close monitoring of their respiratory status. Pleural Effusion • Pathophysiology – Blister-like sac of fluid formed when fluid collects between visceral and parietal pleura Pleural Effusion • Assessment – Hard to hear breath sounds – Position will affect ability to breathe. • Management – Fowler’s position likely most comfortable – Supportive care during transport to hospital Pulmonary Embolism • Pathophysiology – Pulmonary circulation compromised by: • Blood clot • Fat embolism from broken bone • Amniotic fluid embolism during pregnancy • Air embolism from neck laceration or faulty IV Pulmonary Embolism • Pathophysiology (cont’d) – Large embolism usually lodges in major pulmonary artery • Prevents blood flow – Venous blood cannot reach alveoli. Pulmonary Embolism • Assessment – Early presentation: normal breath sounds, good peripheral aeration – Classic presentation: sudden dyspnea and cyanosis, sharp pain in chest • Cyanosis does not end with oxygen therapy. Pulmonary Embolism • Assessment (cont’d) – Often begin in large leg veins, then migrate into pulmonary circulation – Thrombophlebitis: high risk Pulmonary Embolism • Management – Bedridden patients are often given: • Anticoagulants • Special stockings/other devices to reduce blood clot formation – Greenfield filter: opens to catch clots traveling from the legs in the main vein Pulmonary Embolism • Management (cont’d) – Saddle embolus: exceptionally large embolus lodging at left/right pulmonary artery bifurcation • May be immediately fatal • Cape cyanosis despite CPR and ventilation Age-Related Variations • Most common respiratory ailments occur in second half of patient’s life. – Asthma often occurs in younger patients but can flare at any time. Age-Related Variations • Anatomy – Important anatomic differences in children include: • Larger heads relative to body size Age-Related Variations • Pathophysiology – Infants often expend huge amounts of energy to breath and have a limited ability to compensate. – Infants and children with respiratory problems may have: • Respiratory distress • Respiratory failure leading to decompensation • Respiratory arrest Age-Related Variations • Common pediatric respiratory diseases: – Foreign body obstruction of the upper airway – Infections, such as: • Croup • Laryngotracheobronchitis • Epiglottitis • Bacterial tracheitis • Retropharyngeal abscesses Age-Related Variations • Common pediatric respiratory diseases (cont’d): – Lower airway disease – Asthma – Bronchiolitis – Pneumonia – Pertussis (whooping cough) – Cystic fibrosis – Bronchopulmonary dysplasia Summary • Respiratory disease is one of the most common pathologic conditions and reasons for EMS dispatches. • Impaired ventilation may be caused by upper airway obstruction, lower airway obstructive disease, chest well impairment, or neuromuscular impairment. Summary • Respiratory failure occurs from many pathologic conditions. Care includes supplemental oxygen. • Hyperventilation syndrome is excessive ventilation; patient may have chest pain, carpopedal spasm, and alkalosis. • Nasal hairs filter particulates from the air as it flows and is warmed in the nose, humidified, and filtered. Summary • The mouth and oropharynx’s vascular structures are covered with a mucous membrane. The hypopharynx is the junction of the oropharynx and nasopharynx. • The larynx and glottis are the dividing line between upper and lower airways, with the thyroid cartilage the most obvious external larynx landmark. The glottis and vocal cords are in the middle of the thyroid cartilage. Summary • The circoid cartilage forms a complete ring and maintains the trachea in an open position. • The cricothyroid is between the thyroid and circoid cartilages. It is a preferred area for inserting large IV catheters or small breathing tubes. • The respiratory system primary components look like an inverted tree. Summary • The trachea splits into the left and right mainstem bronchi at the carina. • Cilia line the larger airways and help move foreign material out of the tracheobronchial tree. • Pulmonary circulation begins at the right ventricle. Summary • The interstitial space can fill with blood, pus, or air, which causes pain, stiff lungs, and lung collapse. • Ventilation, perfusion, and diffusion are the primary functions of the respiratory system. • Mechanisms of respiratory control are neurologic, cardiovascular, muscular, and renal. Summary • Patients with traumatic brain injuries may exhibit abnormal respiratory patterns. • Respiratory compromise can cause an altered level of consciousness because it cannot store the oxygen it needs to function. • Respiratory disease can cause ventilation, diffusion, and perfusion impairment, or a combination of all three. Summary • Some respiratory diseases have classic presentations. • It is critical to evaluate how hard a patient is working to breathe. • A patient’s position of comfort and speaking difficulty level helps determine degree of distress. • Patients in respiratory distress often use the tripod position. Summary • Signs of life-threatening respiratory distress: – Bony retractions – Soft tissue retractions – Nasal flaring – – – – Tracheal tugging Paradoxical respiratory movement Pursed-lip breathing Grunting Summary • Audible abnormal respiratory noises indicate obstructed breathing. • Snoring indicates partial obstruction of the upper airway by the tongue; stridor indicates narrowing of the upper airway. • Auscultate the lungs to hear adventitious breath sounds, including wheezing and crackles. Summary • Crackles: discontinuous noises heard during auscultation. • Wheezes: high-pitched, whistling sounds from air forced through narrowed airways • If you can’t hear breath sounds with a stethoscope, there is not enough breath to ventilate the lungs. Summary • The respiratory system delivers oxygen and removes carbon dioxide. If the lungs do not work, it can lead to hypoxia, cell death, and acidosis. • Patients with dyspnea are usually transported to the nearest facility. • Patients with chronic respiratory disease may have already tried treatment options. Summary • Determine if the problem started suddenly or gradually worsened as indicators to the underlying cause. • If the condition is recurrent, compare the current incident with other episodes. • If patient cannot speak because of breathing issues, obtain the history from family members or available clues. Summary • Assess the mucous membranes for cyanosis, pallor, and moisture. • Assess the level of consciousness in dyspneic patients. • With the patient in a semisitting position, check for jugular venous distension, which may be caused by cardiac failure. Summary • Feel the chest for vibrations during breathing, and check for edema of the ankles and lower back, peripheral cyanosis, and pulse. Check skin temperature and apply monitors. • A pulse oximeter indicates the percentage of hemoglobin with attached oxygen; greater than 95% is considered normal. Summary • Colorimetric end-tidal carbon dioxide devices or wave capnography can monitor exhaled carbon dioxide. • Peak flow is the maximum flow rate a patient can expel air from the lungs. • Metered-dose inhalers deliver bronchodilators and corticosteroids as an aerosol treatment; dry powder inhalers use a fine powder to deliver a measured-dose treatment. Summary • Aerosol nebulizers deliver a liquid medication in a fine mist. • Emergency care for dyspnea may include: – – – – – – Decreasing work of breathing Supplemental oxygen Bronchodilators Inhaled corticosteroids, vasodilators, or diuretics Supporting or assisting ventilation Intubation Summary • Ensure an open and maintainable airway. Suction if needed, and keep the airway optimally positioned. Remove constrictive clothing. • Inhalation drug administration may be ineffective if airway is compromised. • Medications can be given directly into the tracheobronchial tree if patient is intubated. Summary • CPAP is a respiratory failure therapy that increases oxygen saturation and decreases respiratory rate. • BiPAP is CPAP that delivers one pressure during inspiration and a different one during exhalation. • Automated transport ventilators are flowrestricted oxygen-powered breathing devices with timers. Summary • Patients in respiratory failure may need to be intubated. • Anatomic or foreign body obstruction of the upper airway can cause seizures and death. • Infections can cause upper airway swelling. Croup is one of the most common causes. Summary • Emphysema, chronic bronchitis, and asthma are common obstructive airway diseases, with emphysema and chronic bronchitis collectively classified as COPD. • Asthma is characterized by significant airway obstruction from: – Widespread, reversible airway narrowing – Airway edema – Increased mucous production Summary • Primary treatment for bronchospasms is bronchodilatory medicine, while corticosteroids are the primary treatment for bronchial edema. • Status asthmaticus is a severe, prolonged asthmatic attack that cannot be stopped with conventional treatment. It is a dire emergency. Summary • If an asthma attack is recurring, the inhaler may be empty or the medication ineffective. • Asthma attacks can be triggered by noncompliance with a prescribed medication regimen. • Emphysema is a chronic weakening and destruction of the terminal bronchioles and alveoli walls. Summary • Chronic bronchitis symptoms include: – Excessive mucous production in bronchial tree – Chronic or recurrent productive cough • For patients with COPD, look for cause of a worsened condition. Summary • Hypoxic drive: High oxygen levels decrease the respiratory drive. • When ventilating, allow the patient to exhale completely before the next breath is given to avoid auto-PEEP. • Pneumonia may be caused by bacterial, viral, and fungal agents. Summary • Atelectasis is alveolar collapse from: – Proximal airway obstruction – Pneumothorax – Hemothorax – Toxic inhalation • Lung cancer often presents with hemoptysis and is increasing among women. • Toxic gas inhalation damage depends on the water solubility of the gas. Summary • Pulmonary edema occurs when fluid migrates into the lungs. • Acute respiratory distress syndrome is caused by diffuse alveolar damage from aspiration, pulmonary edema, or other alveolar insult. • In a pneumothorax, air collects between the visceral and parietal pleuras. Administer supplemental oxygen and monitor. Summary • Pleural effusion will cause dyspnea. Give aggressive oxygen administration and proper positioning. • A pulmonary embolism occurs when a blood clot travels to the lungs and blocks blood flow and nutrient exchange. Summary • Infants are less able than older children to compensate for respiratory insults. • Infants and children may be in: – Respiratory distress – Respiratory failure – Respiratory arrest Credits • Chapter opener: © Jones and Bartlett Publishers. Courtesy of MIEMSS. • Backgrounds: Blue—Courtesy of Rhonda Beck; Green—Courtesy of Rhonda Beck; Lime—© Photodisc; Purple—Courtesy of Rhonda Beck. • Unless otherwise indicated, all photographs and illustrations are under copyright of Jones & Bartlett Learning, courtesy of Maryland Institute for Emergency Medical Services Systems, or have been provided by the American Academy of Orthopaedic Surgeons.