title: Do pulmonary function tests improve risk stratification before cardiothoracic surgery?
abstract: OBJECTIVE
  To assess the added value of pulmonary function tests (PFTs) and different classifications of chronic obstructive pulmonary disease (COPD) to the Society of Thoracic Surgeons (STS) risk model using a clinical definition of lung disease for predicting outcomes after cardiothoracic (CT) surgery.
  
  
  METHODS
  We evaluated consecutive patients who underwent nonemergency cardiac surgery and underwent PFTs before CT surgery. We used the STS risk model 2.73 to estimate the postoperative risk for respiratory failure (RF; defined as the need for mechanical ventilation for ≥72 hours, or reintubation), prolonged postoperative stay (PPLS; defined as >14 days), and 30-day all-cause mortality. We plotted the receiver operating characteristics curve for STS score for each adverse event, and compared the resulting area under the curve (AUC) with the AUC after adding PFT parameters and COPD classifications.
  
  
  RESULTS
  Of the 1412 patients with a calculated STS score, 751 underwent PFTs. The AUC of the STS score was 0.65 (95% confidence interval [CI], 0.55-0.74) for RF, 0.67 (95% CI, 0.6-0.74) for prolonged postoperative length of stay (PPLS), and 0.74 (95% CI, 0.6-0.87) for death. None of the PFT parameters or COPD classifications added to the predictive ability of STS for RF, PPLS, or 30-day mortality.
  
  
  CONCLUSIONS
  Adding individual PFT parameters or different COPD classifications to STS score calculated using clinically based classification of lung disease did not improve model discrimination. Thus, routine preoperative PFTS may have limited clinical utility in patients undergoing CT surgery when the STS score is readily available.
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Alexander
authors.initials: A
authors.lastname: Ivanov
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: James
authors.initials: J
authors.lastname: Yossef
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Jordan
authors.initials: J
authors.lastname: Tailon
authors.affiliation: Division of Cardiothoracic Surgery, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Berhane M
authors.initials: BM
authors.lastname: Worku
authors.affiliation: Division of Cardiothoracic Surgery, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Iosif
authors.initials: I
authors.lastname: Gulkarov
authors.affiliation: Division of Cardiothoracic Surgery, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Tortolani
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Terrence J
authors.initials: TJ
authors.lastname: Sacchi
authors.affiliation: Department of Statistical Sciences, Cornell University, Ithaca, NY.
authors.forename: William M
authors.initials: WM
authors.lastname: Briggs
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Sorin J
authors.initials: SJ
authors.lastname: Brener
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY.
authors.forename: Jeremy A
authors.initials: JA
authors.lastname: Weingarten
authors.affiliation: Department of Medicine, New York Methodist Hospital, Brooklyn, NY. Electronic address: jfh9003@nyp.org.
authors.forename: John F
authors.initials: JF
authors.lastname: Heitner
mesh_terms: D000368:Aged; D019540:Area Under Curve; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000401:mortality; D017558:Elective Surgical Procedures; D005260:Female; D006331:Heart Diseases / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007442:Intubation, Intratracheal; D007902:Length of Stay; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D011300:Preoperative Care; D029424:Pulmonary Disease, Chronic Obstructive / Q000145:classification / Q000150:complications / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D012372:ROC Curve; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D012131:Respiratory Insufficiency / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors
keywords: STS risk; pulmonary failure; pulmonary function test