Respiratory Sounds Lab
Nine recordings, one habit: for every sound ask whether it is continuous or discontinuous, high or low, inspiratory or expiratory, and whether a cough changes it. That grid answers most exam questions by itself.
Step 1 · The library
Nine sounds, from vesicular to pleural rub
Start with the three normal breath sounds; everything adventitious is a deviation from them. Every card is a real recording. Ask of each sound: continuous or discontinuous, high or low, inspiration or expiration, and does coughing change it?
Vesicular
Soft, low-pitched. The sound of healthy peripheral lung.
- Pitch
- Low
- Quality
- Soft, attenuated
- Phase
- Throughout inspiration; fades about a third into expiration
- Location
- Over most of the peripheral lung fields
Inspiration-dominantSoftPeripheral lungs
Exam pearl: The baseline: everything else in this lab is a deviation from vesicular.
Bronchial
Loud, tubular. Expiration longer than inspiration.
- Pitch
- High
- Quality
- Loud, hollow, tubular
- Phase
- Expiration longer than inspiration, with a pause between
- Pathological if
- Heard over peripheral lung: fluid or solid consolidation
Expiration-dominantLoudConsolidation if peripheral
Exam pearl: Normal at the manubrium; over peripheral lung it means the airways are transmitting through something solid.
Bronchovesicular
Intermediate pitch. Equal inspiration and expiration.
- Pitch
- Intermediate
- Phase
- Equal inspiratory and expiratory duration
- Location
- 1st and 2nd ICS over the manubrium; between the scapulae
- Note
- Pathological if heard over peripheral lung tissue
Equal I:EManubriumBetween scapulae
Exam pearl: A blend of the other two normals, in the transition zone over the main airways.
Fine Crackles
High-pitched popping, like hair rubbed between fingers.
- Timing
- Late inspiration
- Continuity
- Discontinuous, brief popping or Velcro quality
- Pitch
- High
- Cough
- Not cleared by coughing
Late inspiratoryVelcroFibrosis / pneumonia
Exam pearl: Often diffuse and symmetric in fibrosis. Deep inspiration brings them out.
Coarse Crackles
Low-pitched, bubbling. Fluid in the airways.
- Timing
- Predominantly inspiratory
- Continuity
- Discontinuous, bubbling
- Pitch
- Low
- Pattern
- Symmetric from the bases up in CHF; focal in pneumonia
BubblingCHF from the basesPneumonia if focal
Exam pearl: Symmetry is the clue: CHF fills from the bases upward on both sides; lobar pneumonia stays put.
Wheezes
Continuous, musical. Narrowed lower airways.
- Timing
- Predominantly expiratory; both phases when severe
- Continuity
- Continuous, musical
- Pitch
- High, polyphonic in asthma
- Danger sign
- The silent chest: severe obstruction with almost no airflow
ExpiratoryMusicalAsthma / COPDSilent chest = danger
Exam pearl: The quiet asthmatic chest is not improvement. It is the airway closing.
Stridor
High-pitched, monophonic, inspiratory. Upper airway.
- Timing
- Typically inspiratory
- Quality
- Monophonic, harsh, continuous
- Level
- Upper airway: supraglottis to trachea
- Urgency
- May signal life-threatening obstruction
InspiratoryMonophonicCroupUrgent
Exam pearl: One pitch, one place, on the way IN: large-airway obstruction until proven otherwise.
Rhonchi
Continuous, low-pitched snoring. Secretions.
- Timing
- Both phases, often louder on expiration
- Continuity
- Continuous
- Pitch
- Low, snoring or gurgling
- Key distinction
- May clear with coughing, unlike crackles
ContinuousSnoringClears with coughSecretions
Exam pearl: Ask for a cough, then listen again: rhonchi move, crackles stay.
Pleural Rub
Coarse, leathery, biphasic. Inflamed pleura.
- Timing
- Both phases, biphasic
- Quality
- Coarse, raspy, leathery
- Location
- Localized to the site of pleural inflammation
- Associations
- Pleuritis, effusion, pneumonia, trauma, malignancy
BiphasicLeatheryLocalizedPleuritis
Exam pearl: Two pieces of leather rubbing together, exactly where it hurts to breathe.
Step 2 · Put it together
Findings by condition
Percussion, fremitus, and breath sounds move together. Given any column of this table, you should be able to fill in the rest.
| Finding | Normal | Atelectasis | Pleural effusion | Consolidation (pneumonia) | Pneumothorax |
|---|---|---|---|---|---|
| Percussion | Resonant | Dull | Dull | Dull | Resonant or hyper-resonant |
| Tactile fremitus | Normal | Usually absent | Decreased | Increased or normal | Absent |
| Breath sounds | Vesicular | Absent or decreased | Absent over fluid; bronchial at upper border | Bronchial | Absent or decreased |
| Adventitious sounds | None | None, possible crackles | Absent, or pleural rub above effusion | Crackles | Absent |
Guess the sound
Nine lung sounds, blind
Shuffling the deck…