Objective: To determine whether the frequency of pneumothorax is increased after thoracentesis in chronic obstructive pulmonary disease patients.
Design: Prospective.
Setting: Northeastern community hospital.
Patients: One-hundred-six patients underwent multiple thoracentesis; 36 patients had co-existent chronic obstructive pulmonary disease (mean age, 68.2 years). Chronic obstructive pulmonary disease was identified by radiologic findings consistent with chronic obstructive pulmonary disease and as forced expiratory volume in one second less than 70% of predicted.
Outcome measures: Identification of pneumothorax on chest roentgenogram after thoracentesis.
Intervention: Patients had diagnostic or therapeutic thoracentesis with follow-up chest radiography within 2 hours, or sooner if clinically indicated.
Results: Patients with chronic obstructive pulmonary disease had a higher incidence of pneumothorax (15 of 36 patients; 41.7%) than those patients without underlying chronic obstructive pulmonary disease (13 of 70 patients; 18.5%; p = 0.005). The frequency of pneumothorax was no different according to who performed the procedure (house staff or pulmonologist), whether it was for diagnostic or therapeutic reasons, and whether a small (< 500 ml) or large (> 500 ml) amount of fluid is removed.
Conclusion: Pneumothorax may frequently occur in patients with chronic obstructive pulmonary disease undergoing thoracentesis. The reason may be related to the altered architecture of the lung parenchyma and the change in mechanical forces in chronic obstructive pulmonary disease. Sonography-guided thoracentesis may offer a safer means of performing thoracentesis in patients with chronic obstructive pulmonary disease.