Pulmonary Emergencies. Lower Airway Structures Trachea Bronchial tree Primary bronchi Secondary bronchi Bronchioles Alveoli Lungs

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1 Pulmonary Emergencies Lower Airway Structures Trachea Bronchial tree Primary bronchi Secondary bronchi Bronchioles Alveoli Lungs Pulmonary Surfactant Thin film that coats alveoli Prevents alveoli from collapsing Lungs Principal function is respiration Separated by mediastinum and its contents Base of each lung rests on diaphragm Apex extends 2.5 cm above each clavicle Pleural Cavity Pleural cavity surrounds each lung Two layers Visceral Parietal Pleural space Respiratory System Physiology Gas exchange system Oxygen diffused into bloodstream for cellular metabolism Wastes, including carbon dioxide, are excreted from the body via respiratory system Pathophysiology Related to ventilation, diffusion, perfusion Risk factors for respiratory disease Intrinsic Extrinsic Ventilation Air movement into and out of lungs Depends on: Neurological control to initiate ventilation Nerves between brain stem and respiratory muscles Diaphragm and intercostal muscles Patent upper airway Functional lower airway

2 Functional, expanded alveoli Ventilation Ventilation problems Airway obstruction Chest wall impairment Neurological control Cushings triad bp going up, hr going down, respiration going down. Emergency interventions Open upper and lower airways Assisted ventilation Diffusion Process of gas exchange between alveoli and pulmonary capillary bed Diffusion Gas exchange by simple diffusion Gases move from areas of high concentration to areas of low concentration (until equal) Diffusion Must have: Alveolar and capillary walls that are not thickened Interstitial space between alveoli and capillary wall that is not enlarged or filled with fluid Exchange of Gases in Lungs and Tissue Capillaries Diffusion Problems with diffusion Inadequate oxygen concentration in air Alveolar pathology Interstitial space pathology Capillary bed pathology Diffusion Emergency interventions High concentration oxygen Measures to reduce inflammation in interstitial space Perfusion Circulating blood through pulmonary capillary bed Adequate perfusion needs:

3 Adequate blood volume Adequate hemoglobin Pulmonary capillaries that are not occluded Properly functioning left heart Perfusion Perfusion problems include: Inadequate blood volume Impaired circulatory blood flow Capillary wall pathology Interventions for perfusion problems Ensure adequate circulating volumes and hemoglobin levels Optimize left heart function Initial Assessment Life threatening respiratory distress Alterations in mental status Severe cyanosis Absent breath sounds Audible stridor 1 or 2 word dyspnea Tachycardia Pallor and diaphoresis Retractions and/or use of accessory muscles Focused History and Physical Examination Chief complaints Dyspnea Chest pain Cough Productive Nonproductive Hemoptysis Wheezing Signs of infection Fever, chills Increased sputum production History Previous similar symptoms Known pulmonary diagnosis Medication history Current medications Medication allergies Pulmonary medications Cardiac related drugs History of present episode Exposure and smoking history General Impression Position

4 Sitting Tripod position Feet dangling Mental status Ability to speak 1 or 2 word dyspnea General Impression Respiratory effort Hard work indicates obstruction Retractions Accessory muscle use Skin color Vital signs Pulse Blood pressure Respiratory rate Respiratory pattern Diagnostic Testing Pulse oximetry Peak flow Capnometry Evaluate waveform and CO2 values Before and after treatment (if available) Obstructive Airway Disease Diseases often coexist Chronic bronchitis Emphysema Together called chronic obstructive pulmonary disease Asthma Different degrees of each may be present in same patient Predisposing factors Chronic Bronchitis Inflammatory changes Excessive bronchial mucus production Hyperplasia and hypertrophy of mucusproducing glands Prolonged exposure to irritants Chronic Bronchitis blue bloater Bronchi are filled with excess mucus Cough with sputum production On most days for 3 months/year At least 2 consecutive years Alveoli not seriously affected Diffusion relatively normal Emphysema pink puffer Pathological lung changes Process progresses slowly over many years Characteristics Abnormal enlargement of air spaces beyond terminal bronchioles

5 Destruction of alveoli Failure to maintain alveolar integrity Reduced alveolar surface area Reduced elasticity and air trapping Increased residual volume Vital capacity relatively normal Decrease in PO2 leads to: Increased red blood cell production Polycythemia Emphysema Cystic changes of lobar emphysema resulting from destruction of alveoli Decreases in alveolar membrane surface area and pulmonary capillaries Decreased area for gas exchange Increased resistance to blood flow Expiration muscular act Chest rigid (barrel shaped) Accessory muscles needed to breathe Assessment Acute worsening dyspnea Even at rest Increase or change in sputum Increase in malaise Waking with dyspnea and wheezing Frequent headaches Assessment Respiratory distress Sits upright, leans forward to breathe Pursed lip breathing Maintains positive airway pressure Accessory muscle use COPD Management Medical history IV access ECG monitor Encourage coughing Collect sputum for analysis Oxygen Pulse oximetry, capnometry Assist ventilations, if needed Intubate as necessary Beta agonists Metaproterenol (Alupent) Albuterol (Proventil) Other Steroids (methylprednisolone) Nebulized anticholinergics (ipratropium) Rarely, methylxanthines (aminophylline) Asthma

6 Reactive airway disease Common in children and young adults Triggers usually: Extrinsic in children Intrinsic in adults Child asthma may improve with age Adult asthma usually persistent Asthma Pathophysiology Episodes of variable duration Reversible airflow obstruction due to: Bronchial smooth muscle contraction Mucus hypersecretion Bronchial plugging Inflammatory changes in bronchial walls Asthma Pathophysiology Increased resistance to airflow causes: Alveolar hypoventilation Ventilation perfusion mismatching Hypoxemia Carbon dioxide retention Stimulates hyperventilation Asthma Pathophysiology Increased airway resistance causes air trapping Excessive demand on muscles of respiration Greater accessory muscle use Increases respiratory fatigue Asthma Bronchiole is obstructed on expiration Assessment Upright, leans forward with hands on knees Tripod position Accessory muscles Respiratory distress Rapid, loud respirations Audible wheezing possible Mental status Lethargy, exhaustion, agitation, and confusion signal impending respiratory failure Assessment Auscultation Prolonged expiratory phase Usually wheezing Inspiratory wheezing Secretions in large airways Silent chest may mean severe obstruction Flow too low to generate breath sounds

7 Assessment Other signs of severe asthma Obtundation Diaphoresis and pallor Retractions Dyspnea after 1 2 words Poor, floppy muscle tone Pulse >130 bpm Respirations >30 per min Pulsus paradoxus >20 mm Hg Altered mental status or severe agitation ETCO2 >45 mmhg Asthma Management Airway and Oxygen Reverse bronchospasm Drug therapy based on age and prior medication use IV fluids for rehydration Position to maximize respiratory muscles Monitor for dysrhythmias Brief trial with CPAP Pulmonary Function Tests Peak expiratory flow rate (PEFR) can: Help determine severity Evaluate effectiveness of treatment Peak Flowmeters Cooperative patient (who can make a maximal respiratory effort) and coaching Procedure Status Asthmaticus Severe, prolonged asthma exacerbation not broken with repeated doses of bronchodilators True emergency Requires early recognition Imminent danger of respiratory failure Status Asthmaticus Management As for acute asthma IV fluids for rehydration Continuous bronchodilators Consider BiPAP Status Asthmaticus Management If intubation is needed: Sedate patient RSI if available

8 Albuterol down ET Ventilate at 6 10 breaths per minute Tidal volume 6 8 ml/kg Shorter inspiratory time Longer expiratory time Pneumonia Fifth leading cause of death from infection in U.S. Bacterial, viral, or fungal Spread by: Droplets or contact with infected persons Aspiration of bacteria from nasopharynx Viral, bacterial, mycoplasmal, or aspiration pneumonia Risk factors Viral Pneumonia Influenza A most common viral type Often epidemic in: Schoolchildren Army recruits Nursing home residents May be secondary bacterial pneumonia Viral Pneumonia Presentation Productive cough Pleuritic chest pain Fever Shaking chills Nonspecific complaints (elderly) HA, nonproductive cough, fatigue, sore throat Bacterial Pneumonia Pneumococcal bacillus (streptococcus pneumoniae) Formerly 90% of bacterial pneumonia Peaks in winter and early spring Vaccine 80% 90% effective in adults Since 2000 infants vaccinated Aspiration of oropharyngeal contents Bacterial Pneumonia Risk Factors Infection Foreign body aspiration Alcohol or drug addiction Heart failure Stroke Syncope Pulmonary embolism Chronic respiratory disease Diabetes Congestive heart failure

9 Immobilization Compromised immune status Bacterial Pneumonia Alveoli fill with fluid and purulent sputum Spreads to large areas of lung Lobes fill with fluid, pus V:Q ratio decreases Pneumonia Inflammation of respiratory bronchioles and alveoli caused by infection Mycoplasmal Pneumonia Mild upper respiratory infection in school age children and young adults Transmitted by infected secretions Spreads quickly in families Treated with antibiotics Aspiration Pneumonia Inflammation of lung parenchyma from foreign material in tracheobronchial tree May be: Nonbacterial Bacterial (as a secondary complication) Viral and Mycoplasmal Pneumonia Inflammatory response in bronchi damages ciliated epithelium Congestion Sometimes hemorrhage Signs and symptoms Management Pneumonia Assessment Chest pain Fever Cough Dyspnea Hemoptysis Malaise Upper respiratory and GI symptoms Wheezing Crackles Bacterial Pneumonia Assessment Chills Tachypnea Tachycardia

10 Cough Sputum production Rust color, green, grey, or yellow Malaise Anorexia Back or flank pain Vomiting Aspiration Pneumonia Related to volume and ph of aspirate Low ph Atelectasis, pulmonary edema, hemorrhage, cell necrosis ARDS if severe Dyspnea, cough, bronchospasm, wheezes, crackles, cyanosis Adult Respiratory Distress Syndrome (ARDS) Respiratory failure with: Acute lung inflammation Diffuse alveolar capillary injury ARDS Lungs wet, heavy, congested, stiff Decreased alveolar perfusion Decreased compliance Oxygen Positive pressure ventilation PEEP Positive pressure at end of exhalation Keeps alveoli open Pushes fluid from alveoli into interstitium or capillaries Ventilatory support with PEEP by intubation and use of Boehringer valve CPAP Positive airway pressure Spontaneously breathing patient Increase in airway pressure allows better diffusion of gases and alveolar reexpansion Improves gas exchange Reduces work of breathing Applied Invasively by ET tube Noninvasively by face or nose mask CPAP

11 Reduces inspiratory work of breathing Lowers airway pressures Coach and reassure patient BiPAP Biphasic positive airway pressure Partial ventilatory support and CPAP Noninvasive face or nose mask 5 cm pressure difference between inspiratory positive airway pressure and expiratory positive airway pressure BiPAP Leak tolerant system (CPAP is not) May prevent need for ET intubation COPD, pulmonary edema, pneumonia, and asthma Severe Acute Respiratory Syndrome (SARS) Viral (coronavirus) Cough, dyspnea, hypoxia, chills, aches, fever over F (38 C) Standard and respiratory infection Pulmonary Embolism (PE) Pulmonary artery blocked by clot or other material from remote location Usually lower extremities PE Contributing factors Venostasis Venous injury Increased coagulability Pregnancy Disease (many) Multiple trauma PE Assessment Cough Hemoptysis (rare) Pain Anxiety Syncope Hypotension Pleural friction rub Tachycardia Tachypnea Fever

12 Distended neck veins Localized crackles, wheezing PE Management Oxygen ECG monitor Pulse oximetry IV NS or LR Rapid transport to definitive care Anticoagulants Fibrinolytics Upper Respiratory Infections (URIs) Nose, throat, sinuses, and larynx Cold, pharyngitis, tonsillitis, sinusitis, laryngitis, croup Rarely life threatening Except immune compromised patients Hand washing essential URIs Assessment Sore throat Fever Chills Headache Facial pain (sinusitis) Purulent nasal drainage Bad breath Cervical adenopathy Erythematous pharynx Spontaneous Pneumothorax Often due to subpleural bleb rupture Air enters pleural space from within lung Dyspnea, chest pain, pallor, diaphoresis, tachypnea May be more severe Oxygenate, transport Hyperventilation Syndrome Deep or rapid breathing Excessive carbon dioxide loss Respiratory alkalosis Many causes Some life threatening Hyperventilation Syndrome Dyspnea Tachypnea Hyperpnea Chest pain Circumoral tingling Carpopedal spasm

13 Treat life threats if present If not, calm and coach ventilation Lung Cancer 150,000 new U.S. cases/year Most years of age Smoking top cause Early signs of respiratory illness Lung Cancer Late Hemoptysis Dyspnea Hoarseness Dysphagia Weight loss Weakness Management Oxygenate Transport for definitive care