Which term denotes a nonmusical sound in the lungs?

• A. Tachycardia
• B. Dyspnea
• C. Ronchi
• D. Crackles

Answer: (D)

In lung auscultation, sounds are described by their quality as musical or nonmusical. Crackles are nonmusical, brief popping noises heard during inspiration as air moves through small, reopening airways or through fluid-filled spaces. They can be fine (high-pitched, shorter) or coarse (lower-pitched, longer) and often point to conditions like pulmonary edema, pneumonia, or atelectasis. This nonmusical, explosive quality distinguishes crackles from sounds that have a tonal, musical quality, such as wheezes or rhonchi, which are heard as whistles or snoring/moaning noises due to airway constriction or secretions. Tachycardia and dyspnea describe heart rate and a symptom of breathing difficulty, not lung sounds, so they aren’t terms for lung noises. Therefore, the term that denotes a nonmusical sound in the lungs is crackles.