The safety of thoracentesis in patients with uncorrected bleeding risk

Background: Thoracentesis is commonly performed to evaluate pleural effusions. Many medications (warfarin, heparin, clopidogrel) or physiological factors (elevated International Normalized Ratio [INR], thrombocytopenia, uremia) increase the risk for bleeding. Frequently these medications are withheld or transfusions are performed to normalize physiological parameters before a procedure. The safety of performing thoracentesis without correction of these bleeding risks has not been prospectively evaluated. Methods: This prospective observational cohort study enrolled 312 patients who underwent thoracentesis. All patients were evaluated for the presence of risk factors for bleeding. Hematocrit levels were obtained pre- and postprocedure, and the occurrence of postprocedural hemothorax was evaluated. Measurements and Main Results: Thoracenteses were performed in 312 patients, 42% of whom had a risk for bleeding. Elevated INR, secondary to liver disease or warfarin, and renal disease were the two most common etiologies for bleeding risk, although many patients had multiple potential bleeding risks. There was no significant difference in pre- and postprocedural hematocrit levels in patients with a bleeding risk when compared with patients with no bleeding risk. No patient developed a hemothorax as a result of the thoracentesis. Conclusions: This single-center, observational study suggests that thoracentesis may be safely performed without prior correction of coagulopathy, thrombocytopenia, or medication-induced bleeding risk. This may reduce the morbidity associated with transfusions or withholding of medications.