title: Measured FEV1 in the first postoperative day, and not ppoFEV1, is the best predictor of cardio-respiratory morbidity after lung resection.
abstract: OBJECTIVE
  There is a low correlation between predicted postoperative FEV1 (ppoFEV1) and FEV1 measured the days after pulmonary resection, when most complications are developed. The hypothesis of this investigation is that ppoFEV1 does not predict postoperative morbidity in patients undergoing lung resection when immediate postoperative FEV1 is considered in the predictive model.
  
  
  METHODS
  One hundred ninety-eight consecutive patients undergoing lobectomy or pneumonectomy were included in a prospective, multiinstitutional study.
  
  
  METHODS
  age, body mass index, ppoFEV1, surgical approach (VATS or muscle-sparing thoracotomy), type of analgesia (epidural or intraveous), postoperative visual analogue pain score and FEV1 measured the day after the operation. Target variable: occurrence of postoperative cardio-respiratory complications. Method of analysis: classification tree (CART) dividing the population at random in two subsets and developing a bootstrap set of 100 trees resampling training data. The relative importance of each variable and the accuracy of both initial and committee trees to predict the outcome were presented.
  
  
  RESULTS
  One hundred seventy-seven lobectomies and 21 pneumonectomies were included. Overall cardio-respiratory morbidity was 22%. According to CART results, first day FEV1 was the most important variable to classify cases as primary splitter and as a surrogate of each primary splitter (100% importance). Patient age followed (51%) and ppoFEV1 was third (43%) with a score similar to postoperative pain score (42%) and type of analgesia (36%). Sensitivity and specificity of the initial tree were, respectively, 0.5 and 0.7; values for committee tree were 0.5 sensitivity and 0.7 specificity.
  
  
  CONCLUSIONS
  Postoperative cardio-respiratory complications are more related to FEV1 measured in the first postoperative day than to ppoFEV1 value.
authors.affiliation: Service of Thoracic Surgery, Salamanca University Hospital, 37007 Salamanca, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Varela
authors.forename: Alessandro
authors.initials: A
authors.lastname: Brunelli
authors.forename: Gaetano
authors.initials: G
authors.lastname: Rocco
authors.forename: Nuria
authors.initials: N
authors.lastname: Novoa
authors.forename: Majed
authors.initials: M
authors.lastname: Refai
authors.forename: Marcelo F
authors.initials: MF
authors.lastname: Jiménez
authors.forename: Michele
authors.initials: M
authors.lastname: Salati
authors.forename: Tindaro
authors.initials: T
authors.lastname: Gatani
mesh_terms: D000367:Age Factors; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000209:etiology; D004812:Epidemiologic Methods; D005260:Female; D005541:Forced Expiratory Volume; D006331:Heart Diseases / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis; D011013:Pneumonectomy / Q000009:adverse effects*; D011182:Postoperative Care / Q000379:methods*; D011379:Prognosis; D012120:Respiration Disorders / Q000175:diagnosis* / Q000209:etiology; D020775:Thoracic Surgery, Video-Assisted