Clinical Yield of Routine Chest Radiography after Ultrasound-Guided Thoracentesis

To evaluate the clinical yield of routine chest radiography in identifying pneumothorax warranting chest tube decompression in patients undergoing ultrasound-guided thoracentesis.

All adult patients without pre-existing pneumothorax who underwent ultrasound-guided thoracentesis by a radiologist within a four-hospital large metropolitan academic health system over a 10-year period were identified. Demographic, clinical, and radiographic report information were obtained. Chest radiographic reports were assessed for the presence of pneumothorax and, if positive, manual image and chart review were performed.

Of 2541 consecutive ultrasound-guided thoracentesis procedures, 12 were excluded due to pre-existing pneumothorax, yielding 2529 cases. Mean patient age was 67.7 years; 54.5% were male. Overall, 89 procedures (3.5%) resulted in a postprocedural pneumothorax. Of those, only six (6.7%) had documented changes in patient symptoms. Chest tubes were placed in 15, representing 16.9% (15/89) of cases with postprocedural pneumothoraces and 0.59% (15/2,529) of all procedures. Of these 15, 5 (33.3%) had symptomatic pneumothoraces, most commonly shortness of breath.

Following ultrasound-guided thoracentesis, the incidence of pneumothorax requiring chest tube decompression is only 1 in 170. Of the 1 in 30 patients who develop a pneumothorax, only 1 in 6 require a chest tube. This information can inform procedural consent discussions as well as future guidelines about the necessity of routine postprocedural chest radiography.