Estimating the Risk of Prolonged Air Leak after Pulmonary Resection Using a Simple Scoring System

BACKGROUND: The high rate of prolonged air leak (PAL) after pulmonary resection has prompted interest in surgical adjuncts designed to prevent this complication. However, these adjuncts are costly and might not be beneficial if used routinely. Identification of patients at highest risk might allow for more effective use of these adjuncts. Therefore, we sought to develop a simple scoring system to predict PAL. STUDY DESIGN: A derivation set of 580 patients was identified from a prospectively entered database of consecutive pulmonary resections at a single institution from 2002 to 2007. Patient and operative characteristics were compared using Student's t-test and chi-square tests. Significant variables on univariate analysis were entered into a stepwise logistic regression to establish a simple predictive model to estimate the risk of PAL. This scoring system was then validated in a consecutive set of 381 patients operated at the same institution from 2007 to 2009. RESULTS: The rate of PAL was 14% in the derivation set and 18% in the validation set. Poor pulmonary function (forced expiratory volume in 1 second and carbon monoxide diffusing capacity, percent predicted) and pleural adhesions were significantly associated with PAL in the derivation set. A weighted scoring system was devised using pleural adhesions (+2 points), forced expiratory volume in 1 second (+1 per 10% below 100%), and carbon monoxide diffusing capacity (+1 per 20% below 100%). Total number of points estimated the probability of PAL. Hosmer-Lemeshow goodness-of-fit test confirmed validity (p > 0.2) of this scoring system in the validation set. CONCLUSIONS: We have devised and validated a simple scoring system to predict the probability of PAL after pulmonary resection.