title: Continuous pulse oximetry and the diagnosis of pulmonary embolism in critically ill trauma patients.
abstract: The diagnosis of pulmonary embolism (PE) may be difficult to establish in trauma patients, particularly those who are unresponsive or mechanically ventilated. Based on a prior retrospective study, we hypothesized that patients monitored by continuous pulse oximetry who experienced a 10% or greater sudden sustained drop in arterial oxygen saturation (SaO2) without a change in static lung compliance (Cst) were most likely to have had a PE. We followed SaO2 in 972 patients admitted to our trauma ICU during the 18-month period ending in December 1990. Forty-eight patients (5%) with SaO2 changes, but no Cst changes, were evaluated for suspected PE using pulmonary arteriography (PA). Of these, 21 (44%) had a positive PA study. All patients with a positive PA had either clear chest roentgenograms or no change in underlying pulmonary pathologic processes. Of the remainder, 26 had evidence of a new pathologic entity on chest roentgenograms and only one patient had a SaO2 decrease, no change in Cst, and a negative PA. All mechanically ventilated trauma patients should have SaO2 monitored continuously. Patients with a > 10% drop in Sao2 with no change in Cst and no new roentgenographic chest findings should undergo PA. Based on our experience, this approach would yield a sensitivity, specificity, and predictive value of 100%, 99.9%, and 95%, respectively, for the diagnosis of clinically significant PE.
authors.affiliation: Department of Surgery, Cooper Hospital/University Medical Center, Camden, New Jersey.
authors.forename: C E
authors.initials: CE
authors.lastname: Brathwaite
authors.forename: K F
authors.initials: KF
authors.lastname: O'Malley
authors.forename: S E
authors.initials: SE
authors.lastname: Ross
authors.forename: P
authors.initials: P
authors.lastname: Pappas
authors.forename: J
authors.initials: J
authors.lastname: Alexander
authors.forename: R K
authors.initials: RK
authors.lastname: Spence
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001785:Blood Gas Monitoring, Transcutaneous; D016638:Critical Illness; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010092:Oximetry; D011655:Pulmonary Embolism / Q000150:complications / Q000175:diagnosis*; D014947:Wounds and Injuries / Q000150:complications*