title: Estimating the risk of prolonged air leak after pulmonary resection using a simple scoring system.
abstract: 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.
  
  
  METHODS
  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.
authors.affiliation: Department of Surgery, Division of Thoracic Surgery, McGill University Health Center, Montreal, QC, Canada.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Lee
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hanley
authors.forename: Catherine
authors.initials: C
authors.lastname: Robineau
authors.forename: Christian
authors.initials: C
authors.lastname: Sirois
authors.forename: David S
authors.initials: DS
authors.lastname: Mulder
authors.forename: Lorenzo E
authors.initials: LE
authors.lastname: Ferri
mesh_terms: D000368:Aged; D000388:Air; D000704:Analysis of Variance; D002170:Canada / Q000453:epidemiology; D002248:Carbon Monoxide / Q000378:metabolism; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010995:Pleural Diseases / Q000150:complications / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D011013:Pneumonectomy / Q000009:adverse effects*; D011030:Pneumothorax / Q000209:etiology / Q000601:surgery; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013396:Suction; D000267:Tissue Adhesions / Q000209:etiology
chemical_list: D002248:Carbon Monoxide