From the Guidelines
The auscultation finding that is often described as sounding like "walking on snow" is "velcro" crackles, which are characteristic of lung fibrosis, as noted in the most recent study 1. This finding occurs when there is scarring or fibrosis in the lungs, typically due to conditions such as idiopathic pulmonary fibrosis (IPF) or interstitial lung disease (ILD). When you place your stethoscope over an area with lung fibrosis and apply gentle pressure, you'll hear a characteristic crackling sensation that resembles the sound of walking on fresh snow or crushing Rice Krispies cereal. This occurs because the scarred lung tissue is being compressed and moved against each other. The presence of "velcro" crackles should prompt investigation for underlying causes such as IPF, ILD, or other conditions that may require urgent intervention, as noted in the study 1. Key points to consider include:
- The clinical evaluation must include a search for clinical features suggestive of connective tissue disease (CTD) 1
- High-resolution computed tomography (HRCT) is the primary imaging tool used to detect ILD and outline its extension and pattern 1
- Pulmonary function tests (PFTs) are also a reliable tool for early ILD detection, and detection of decreased diffusing capacity for carbon monoxide (DLCO) can aid an early diagnosis 1
From the Research
Auscultation Findings
- There are no research papers provided that directly describe an auscultation finding as being like walking on snow 2, 3.
- The provided studies discuss the importance of auscultation in diagnosing respiratory disorders 2 and an algorithmic approach to interpreting diffuse lung disease on chest CT imaging 3, but do not mention a specific auscultation finding that resembles walking on snow.
- Further research may be necessary to find a study that describes an auscultation finding with this specific characteristic.