title: A scoring system to predict unplanned intubation in patients having undergone major surgical procedures.
abstract: BACKGROUND
  Unplanned tracheal intubation after surgery has been associated with high mortality. Few studies have examined the risk factors for this complication.
  
  
  METHODS
  The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) is a multicenter, prospective, outcome-oriented database for patients having undergone major surgical procedures. Using the NSQIP data for the years 2005 to 2007 (n = 231,548) and Cox proportional hazards modeling, we identified risk factors and used them to derive a scoring system to stratify patients' risk of having an unplanned intubation outcome. NSQIP data for the year 2008 (n = 176,031) were then used to validate the scoring system.
  
  
  RESULTS
  The variables most predictive of unplanned intubation were patient age (0-4 points), ASA physical status (0-7 points), the presence of preoperative sepsis (3 points), and total operative time (0-4 points). The Unplanned Intubation Risk Index based on the adjusted hazard ratios for these variables, ranging from 0 (lowest risk) to 18 (highest risk), had a 79% accuracy in distinguishing patients requiring unplanned intubation from those not requiring it (area under the receiver operating characteristic curve 0.79, 95% confidence interval 0.79-0.80). When the scoring system was applied to the validation cohort data, its discriminative performance remained virtually unchanged (area under the receiver operating characteristic curve 0.79, 95% confidence interval 0.79-0.80).
  
  
  CONCLUSIONS
  A scoring system based on clinical risk factors was able to accurately predict unplanned intubation after surgery. Further investigation is needed to assess the utility of the Unplanned Intubation Risk Index in reducing the incidence of unplanned intubation through improved risk stratification and management in perioperative care.
authors.affiliation: Department of Anesthesiology, Columbia University College of Physicians and Surgeons, 622 West 168th St., PH5, Room 535, New York, NY 10032, USA. mh2633@columbia.edu
authors.forename: May
authors.initials: M
authors.lastname: Hua
authors.forename: Joanne E
authors.initials: JE
authors.lastname: Brady
authors.forename: Guohua
authors.initials: G
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D005260:Female; D006304:Health Status; D017052:Hospital Mortality; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000401:mortality; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D018805:Sepsis / Q000150:complications; D013997:Time Factors; D014481:United States; D055815:Young Adult