title: Use of pulse oximetry to predict in-hospital complications in normotensive patients with pulmonary embolism.
abstract: OBJECTIVE
  A simple method is needed to risk stratify normotensive patients with pulmonary embolism. We studied whether bedside clinical data can predict in-hospital complications from pulmonary embolism.
  
  
  METHODS
  We performed a multicenter derivation phase, followed by validation in a single center. All patients were normotensive; the diagnosis of pulmonary embolism was established by objective imaging. Classification and regression analysis was performed to derive a decision tree from 27 parameters recorded from 207 patients. The validation study was conducted on a separate group of 96 patients to determine the derived criterion's diagnostic accuracy for in-hospital complications (cardiogenic shock, respiratory failure, or death).
  
  
  RESULTS
  Mortality in the derivation phase was 4% (n = 8) at 24 hours and 10% (n = 21) at 30 days. A room-air pulse oximetry reading <95% was the most important predictor of death; mortality was 2% (95% confidence interval [CI]: 0% to 6%) in patients with pulse oximetry >or=95% versus 20% (95% CI: 12% to 29%) with pulse oximetry <95%. In the validation phase, the room-air pulse oximetry was <95% at the time of diagnosis in 9 of 10 patients who developed an in-hospital complication (sensitivity, 90%) and >or=95% in 55 of 86 patients without complications (specificity, 64%).
  
  
  CONCLUSIONS
  Mortality from pulmonary embolism in normotensive patients is high. A room-air pulse oximetry reading >or=95% at diagnosis is associated with a significantly lower probability of in-hospital complications from pulmonary embolism.
authors.affiliation: Department of Emergency Medicine, Carolinas Medical Center, Charlotte, North Carolina 28323-2861, USA. JKline@carolina.rr.com
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Kline
authors.forename: Jackeline
authors.initials: J
authors.lastname: Hernandez-Nino
authors.forename: Craig D
authors.initials: CD
authors.lastname: Newgard
authors.forename: Dana N
authors.initials: DN
authors.lastname: Cowles
authors.forename: Raymond E
authors.initials: RE
authors.lastname: Jackson
authors.forename: D Mark
authors.initials: DM
authors.lastname: Courtney
mesh_terms: D001794:Blood Pressure / Q000502:physiology; D006760:Hospitalization; D006801:Humans; D010092:Oximetry / Q000592:standards*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D015203:Reproducibility of Results; D012131:Respiratory Insufficiency / Q000209:etiology / Q000517:prevention & control*; D018570:Risk Assessment / Q000379:methods; D012680:Sensitivity and Specificity; D012770:Shock, Cardiogenic / Q000209:etiology / Q000517:prevention & control*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology