Prehospital Treatment of Dyspnea with CPAP

Mark Marchetta, BS, RN, NREMT-P

Director, EMS EducationAultman Health Foundation

Canton, Ohio

What is CPAP

CONTINUOUS

POSITIVE

AIRWAY

PRESSURE

Review of Respiratory Emergencies

Respiratory System Anatomy and Physiology

Respiratory Medical Terminology

Respiratory Emergencies / Pathophysiology

Normal Process

Chest Wall

VentilationVentilation 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

musclesA patent upper airwayAlveoli 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 bedIn 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 somethingcauses 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 hyperventilationLeads to…respiratory fatigue

AssessmentTripod 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”PneumoniaCOPDForeign body aspirationHeart failurePneumothoraxPulmonary embolismToxic 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 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 wallscigarette smokingexposure 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 / confusionmay 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 DistressOrthopnea (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 CongestionCrackles Wheezing??

JVD

Signs and Symptoms

Vital SignsSympathetic NS discharge Blood pressure early BP later as pt. tires… bad sign!TachycardiaResp 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!

Continuous Positive Airway Pressure

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.