Lung Sounds for EMT-B: Crackles, Wheezes, Stridor, and What Each Means

Lung sounds are an EMT-B assessment finding. They are not a reason to invent ALS-level treatment or make a hospital diagnosis in the field. Your job is to hear what is happening, connect it to breathing and perfusion, treat within scope, request ALS when appropriate, and reassess.

That framing matters. Lung sounds are useful because they change priority and treatment decisions. They help you decide whether oxygen, positioning, suction, BVM ventilation, albuterol assistance, epinephrine auto-injector, CPAP where authorized, ALS intercept, or rapid transport is needed.

Wheezes

Wheezes are often heard with bronchospasm. Students usually associate them with asthma, but wheezing can also appear in COPD or allergic reactions. At the EMT-B level, the action is to assess severity, check SpO2, consider oxygen, assist with the patient's prescribed albuterol MDI if allowed, and request ALS for severe distress or poor response.

Do not let wheezing distract from work of breathing. A patient who is tiring, altered, cyanotic, or unable to speak needs rapid escalation.

Crackles

Fine crackles at the bases can suggest fluid in the alveoli, often discussed in CHF training. EMT-B actions include positioning upright, oxygen support, CPAP if authorized by local protocol, vital sign trending, ALS request for severe distress, and transport. Do not treat crackles as a diagnosis by themselves. Combine them with history, skin signs, edema, blood pressure, and respiratory effort.

Stridor

Stridor is an upper airway warning sound. In allergic reactions, stridor plus swelling, hives, respiratory distress, or hypotension should make you think about anaphylaxis and epinephrine auto-injector per protocol. Stridor can deteriorate quickly. Keep airway equipment ready, provide oxygen, request ALS, and transport.

Rhonchi

Rhonchi can sound coarse and may suggest secretions in larger airways. EMT-B care includes positioning, suction when indicated, oxygen, and reassessment. If the patient cannot protect their airway or is deteriorating, escalate quickly.

Absent or unequal breath sounds

Absent unilateral breath sounds after trauma are a high-risk finding. EMT-Bs do not perform needle decompression in the national scope. The EMT-B action is rapid recognition, oxygen or ventilation support, rapid transport, hospital notification, and ALS intercept.

How to document lung sounds

Document what you heard, where you heard it, and what changed. "Wheezes bilateral upper fields, SpO2 89%, improved to 94% after oxygen and prescribed MDI assistance" is stronger than "asthma." The first sentence is an assessment trail. The second is a label.