1.1 Crackles (crepitation)
• Most typical causes are pulmonary edema and pneumonia
in its early stages
• Because gravity draws fluid downward, often start in
bases of lungs
• May be classified further as coarse crackles (wet, low‐
pitched sounds) or fine crackles (dry, high‐pitched sounds)
• Are discrete and sometimes difficult to hear and may be
overridden by louder respiratory sounds
• If suspected crackles when auscultating chest, patient
should be asked to cough
• Cough may clear secretions and make crackles more
audible