Bedside sonography for detection of postprocedure pneumothorax

Abstract

Objectives: Bedside sonography for diagnosis of pneumothorax has been well described in emergency and trauma medicine literature. Its role in detection of iatrogenic pneumothorax has not been well studied. We describe the performance of bedside sonography for detection of procedure-related pneumothorax and highlight some limitations.

Methods: A total of 185 patients underwent thoracentesis (n = 60), transbronchial biopsy (n = 48), and computed tomography-guided needle lung biopsy (n = 77). Bedside preprocedure and postprocedure transthoracic sonography and postprocedure chest radiograph were performed in all patients. Patients in whom the pleural surface was not well imaged with sonography were said to have a limited examination. Chest radiography was the standard for diagnosing pneumothorax.

Results: Chest radiography showed pneumothorax in 8 of 185 patients (4.0%). These patients had undergone computed tomography-guided needle lung biopsy (n = 7) and transbronchial needle lung biopsy (n = 1). Sonography showed pneumothorax in 7 of these patients. The sensitivity, specificity, and diagnostic accuracy were 88%, 97%, and 97%, respectively. Limited-quality sonographic examinations due to preexisting lung disease were seen in 43 of 185 patients. The positive and negative likelihood ratios for patients with adequate scans were 55 and 0.17, respectively. The likelihood ratio for patients with limited-quality scans was 1.08.

Conclusions: When a good-quality scan is achieved, bedside chest sonography is a valuable tool for evaluation of postprocedure pneumothorax. Patients with preexisting lung disease, in whom the quality of the sonographic examination is limited, should be studied with chest radiography.

Keywords: biopsy; pneumothorax; sonography.

Figures

Figure 1

Ultrasound image comparing normally aerated lung with pneumothrax

Figure 3

Bullous Emphysema Resulting in False Positive Ultrasound Scan