Prehospital Treatment of Dyspnea with CPAP Mark Marchetta, BS, RN, NREMT-P Director, EMS Education Aultman Health Foundation Canton, Ohio

What is CPAP C ONTINUOUS P OSITIVE A IRWAY P RESSURE

Review of Respiratory Emergencies Respiratory System Anatomy and Physiology Respiratory Medical Terminology Respiratory Emergencies / Pathophysiology

Normal Process

Chest Wall

Ventilation Ventilation refers to the process of air movement in and out of the lungs The following must be intact for ventilation to occur: Functional diaphragm and intercostal muscles A patent upper airway Alveoli that are functional

Diffusion Diffusion – the movement of gas from an area of higher concentration to an area of lower concentration In the respiratory cycle this refers to the movement of oxygen and carbon dioxide

Diffusion In order for diffusion to occur, the following must be intact: Alveoli and capillary walls are functional Interstitial space between the alveoli and capillary wall that are not enlarged or filled with fluid

Perfusion Refers to the process of circulating blood through the pulmonary capillary bed In order for perfusion to occur, the following must be intact: A properly functioning heart (pump) Proper vascular “size” Adequate blood volume / hemoglobin

Respiratory Emergencies Asthma – Bronchitis – Emphysema Pneumonia – CHF / Pulmonary Edema

Asthma A chronic inflammation disorder in the airways Acute episodes “triggered” by something causes release of histamine, leukotrienes causes obstruction of airflow

Pathophysiology Bronchial smooth muscle constriction Bronchial plugging from mucus secretion Inflammation changes

Pathophysiology Increased resistance to airflow! Hypoxemia and carbon dioxide retention Stimulates hyperventilation Leads to…respiratory fatigue

Assessment Tripod Position Wheezing A silent chest is an ominous sound! Flow rates are too low to generate breath sounds Inability to speak Pulse > 130, Respirations >30

Differential Diagnosis “All that wheezes is not asthma” Pneumonia COPD Foreign body aspiration Heart failure Pneumothorax Pulmonary embolism Toxic inhalation

COPD

Bronchitis Can be chronic or acute Inflammation of the bronchioles with large amounts of sputum present SOB because of mucus in alveoli

Signs and Symptoms History of resp. infection Productive cough of large quantity of sputum SOB Cyanosis

Mucus Inspiration – Air Can get in… Expiration – Air Can’t get out…

The Mucus Obstruction Leads to trapping of air Hyperinflation occurs permanent damage Is the reason chronic bronchitis is classified at COPD

“Blue Bloater” Diagnosed by several findings including a productive cough 3 months of the year for 2 consecutive years

Emphysema Chronic disease Result of destruction of the alveolar walls cigarette smoking exposure to “unfriendly” environment

Signs and Symptoms Skinny! SOB all the time SOB worsens with any activity Barrel chest Long expiratory phase – Pursed lip Pink in color (polycythemia)

“Pink Puffer”

Pneumonia Infection of the lung (in the alveoli) Bacteria or virus invade the lung and multiply Body sends WBC to fight infection Causes “consolidation” in alveoli

Pneumonia Assessment Patient looks “ill” History of fever Productive cough with yellow tan green Localized wheezing / rhonchi in affected lobe, breath sounds may be diminished

Pneumonia Assessment ELDERLY Altered mental status / confusion may be only symptom Fever Cough

Pneumonia Management Supportive Bronchodilators may provide some symptomatic relief if bronchospasm is present

“Heart Failure”

Pathophysiology Left ventricle cannot effectively pump forward Left atrial pressure rises Back pressure of fluid into pulmonary circulation

Signs and Symptoms Respiratory Distress Orthopnea (must sit or stand to breath comfortably) Spasmodic coughing (pink frothy sputum) Paroxysmal Nocturnal Dyspnea Severe Apprehension, Confusion, “Smothering Feeling” Due to hypoxia

Signs and Symptoms Cyanosis – due to poor exchange of O2 at alveoli level Diaphoretic Pulmonary Congestion Crackles Wheezing?? JVD

Signs and Symptoms Vital Signs Sympathetic NS discharge  Blood pressure early  BP later as pt. tires… bad sign! Tachycardia  Resp rate early (40’s)  resp rate as pt. tires

Signs and Symptoms Chest Pain Incident may have started with chest pain (AMI) May not C/O chest pain because too busy working to breath

Management Goals Improve oxygenation  venous return to the heart  myocardial oxygen demand

Assessment IF YOU CAN’T TELL WHETHER A PATIENT IS MOVING AIR ADEQUATELY, THEY AREN’T THE NEED TO INTUBATE IS NOT THE SAME AS THE NEED TO VENTILATE! IF YOU THINK ABOUT GIVING O2, GIVE IT!

C ontinuous P ositive A irway P ressure Measured in cmH2O Pressure

CHF

Benefits/Advantages of CPAP CPAP reduces work of breathing by keeping the “wet” alveoli open If the alveoli are open at the end of expiration, energy is not consumed on the next inhalation Work of breathing is reduced relieving respiratory muscle fatigue

Benefits/Advantages of CPAP A higher alveoli pressure will result in a stoppage of fluid movement into the alveoli Increase in airway pressure results in improved gas exchange

What about the Asthma Patient?

Asthma CPAP will facilitate the delivery of oxygen and medication Albuterol through the CPAP mask

What About Patients With Bronchitis and Pneumonia?

Bronchitis / Pneumonia CPAP will facilitate the delivery of oxygen and/or medication Albuterol through the CPAP mask if indicated

What about the Emphysema Patient?

Important Point Emphysema patients do not respond predictably to CPAP

As a general rule… The larger the “barrel chest” and the more pronounced the accessory muscles, the more caution we should use with CPAP

CPAP Protocol Review

CPAP Study Results

Skills Lab It is recommended that this lecture is followed by a skills lab to demonstrate CPAP use. The vendor who sells the CPAP product can provide the demonstration.