Respiratory / Lung Assessment

Crackles and rhonchi can sound similar through a stethoscope, but confusing them changes your entire clinical response. Knowing where, how, and what you're hearing is the skill NCLEX tests.

Respiratory assessment follows a systematic approach: inspect, palpate, percuss, auscultate. Inspection includes respiratory rate (normal 12–20 breaths/min in adults), rhythm, depth, symmetry of chest expansion, use of accessory muscles, nasal flaring, and pursed-lip breathing. Palpate for tactile fremitus — it increases over consolidated tissue (pneumonia) and decreases with pleural effusion or pneumothorax. Percuss for resonance (normal lung), hyperresonance (trapped air, as in emphysema or pneumothorax), and dullness (fluid or consolidation). Auscultate bilaterally, comparing side to side, using the diaphragm of the stethoscope over at least six posterior fields. Normal breath sounds include vesicular (soft, over peripheral lung fields), bronchovesicular (moderate, near mainstem bronchi), and bronchial (loud, over trachea). Adventitious sounds carry specific meaning: crackles (rales) — fine, discontinuous popping heard on inspiration — indicate fluid in alveoli. Rhonchi — low-pitched, continuous rumbling — suggest mucus in larger airways and often clear with coughing. Wheezes — high-pitched, musical — signal narrowed airways. Stridor — high-pitched on inspiration — is an emergency indicating upper airway obstruction. Document location, timing in the respiratory cycle, and whether sounds change after coughing or repositioning.

Key Distinctions

Don't confuse crackles with rhonchi: crackles are discontinuous popping (fluid in alveoli) while rhonchi are continuous rumbling (mucus in airways) that often clear with coughing. Students mix up hyperresonance (air trapping, pneumothorax) with dullness (fluid, consolidation) — they are opposite percussion findings. Stridor is upper airway and inspiratory; wheezes are lower airway and commonly expiratory — stridor is always urgent.

Clinical Pearl

Compare side to side, not top to bottom. If the right lower lobe sounds different from the left lower lobe, that asymmetry is your finding — document it and act on it.