Hemopneumothorax Missed by Auscultation in Penetrating Chest Injury

OBJECTIVE: To determine the frequency and extent of hemothorax, pneumothorax, and hemopneumothorax missed by auscultation in penetrating chest injury. DESIGN: A retrospective chart and chest radiograph review. MATERIALS AND METHODS: One hundred and eighteen patients suffering penetrating chest injuries during 1993 were studied. A missed auscultation was defined as a patient with normal breath sounds but shown by chest radiograph to have a hemothorax, pneumothorax, or hemopneumothorax. The amount of hemothorax was recorded after chest tube placement or at thoracotomy. The degree of pneumothorax was determined by Rhea's method. RESULTS: Seventy-one patients (60%) had a hemothorax, pneumothorax, or hemopneumothorax. Auscultation to detect hemothorax, pneumothorax, or hemopneumothorax had a sensitivity of 58%, a specificity of 98%, and a positive predictive value of 98%. Thirty of 71 patients (42%) were found to have pleural space blood or air missed by auscultation. Twelve patients (41%) had a hemopneumothorax, 11 patients (36%) had hemothorax, and seven patients (23%) had pneumothorax. Auscultation missed hemothorax up to 600 mL, pneumothorax up to 28%, and hemopneumothorax up to 800 mL and 28%. CONCLUSION: Hemopneumothorax and hemothorax are the conditions most likely to be missed by auscultation, especially in patients with gunshot wounds. Auscultation has a high positive predictive value because it indicates injury with a fair degree of certainty; however, a negative auscultation does not rule out injury.