Should chest drains be put on suction or not following pulmonary lobectomy?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether the use of suction applied to chest drains in patients undergoing lobectomy reduces the incidence of prolonged air leak. Altogether 391 papers were found using the reported search, of which 6 represented the best evidence on this topic, including 5 well conducted prospective randomised controlled trials. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. We conclude that of the 6 studies presented, no studies found in favour of suction to reduce the incidence of air leak, 2 studies found no difference between the two strategies, and 4 studies found evidence that water seal drainage without suction reduced the incidence of air leak. Five of the 6 studies used a short period of suction in the immediate post-operative period and the one study looking at immediate water seal drainage found no differences in outcome. Exceptions to the water seal strategy may be patients with a large air leak, or a large pneumothorax on CXR.