title: Use the Lower Limit of Normal, Not 80% Predicted, in Judging Eligibility for Lung Resection.
abstract: BACKGROUND
  Impaired lung function (LF) is a well-known risk factor for perioperative complications in patients qualified for lung resection surgery. The recent European guidelines recommend using values below 80% predicted as indicating abnormal LF rather than the lower limit of normal (LLN).
  
  
  OBJECTIVE
  To assess how the choice of a cut-off point (80% predicted vs. LLN at -1.645 SD) affects the incidence of functional disorders and postoperative complications in lung cancer patients referred for lung resection.
  
  
  METHODS
  Preoperative spirometry and the transfer factor for carbon monoxide (TL,CO) were retrospectively analysed in 851 consecutive lung cancer patients after resectional surgery.
  
  
  RESULTS
  Airway obstruction was diagnosed in 369 (43.4%), and a restrictive pattern in 41 patients (4.8%). The forced expiratory volume in 1 s (FEV1) or TL,CO was below the LLN in 503 patients (59.1%), whereas the FEV1 or TL,CO was <80% predicted in 620 patients (72.9%; χ2 test: p < 0.0001). In all, 117 out of 851 patients had LF indices <80% predicted but not below the LLN. Odds ratios (ORs) for perioperative complications were higher in patients with impaired LF indices defined as below the LLN (1.59, p = 0.0005) with the exception of large resections (>5 segments). In patients with test results above the LLN and <80% predicted, the OR for perioperative complications was not different (1.14, p = 0.5) from that in patients with normal LF.
  
  
  CONCLUSIONS
  LF impairments are common in candidates for lung resection. Using the LLN instead of 80% predicted diminishes the prevalence of respiratory impairment by 14% and allows for safe resectional surgery without additional function testing.
authors.affiliation: Departments of Lung Pathophysiology, National Tuberculosis and Lung Disease Research Institute, Warsaw, Poland.
authors.forename: Stefan P
authors.initials: SP
authors.lastname: Wesolowski
authors.forename: Piotr W
authors.initials: PW
authors.lastname: Boros
authors.forename: Tadeusz M
authors.initials: TM
authors.lastname: Orłowski
authors.forename: Philip H
authors.initials: PH
authors.lastname: Quanjer
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011013:Pneumonectomy; D011044:Poland / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D012120:Respiration Disorders / Q000453:epidemiology*; D012129:Respiratory Function Tests; D012189:Retrospective Studies