title: Both hypoxemia and extreme hyperoxemia may be detrimental in patients with severe traumatic brain injury.
abstract: An association between hypoxemia and poor outcomes from traumatic brain injury (TBI) is well documented. However, it is unclear whether hyperoxygenation is beneficial. This registry-based analysis explores the relationship between early hypoxemia and hyperoxemia on outcome from moderate-to-severe TBI. TBI patients (Abbreviated Injury Scale score 3+) were identified from the San Diego County trauma registry. Patients were stratified by arrival partial oxygen pressure (Po(2)) value. Trauma and injury severity score (TRISS) was then used to calculate predicted survival for each patient, with the mean observed-predicted survival differential determined for each arrival Po(2) stratification. Logistic regression was used to quantify the relationship between hypoxemia, hyperoxemia, and outcome from TBI after adjusting for multiple variables including intubation and ventilation status. A total of 3420 patients were included in the analysis. TRISS calculations revealed worse outcomes than predicted for both hypoxemia and extreme hyperoxemia. Logistic regression revealed an optimal Po(2) range (110-487 mm Hg), with an independent association observed between decreased survival and both hypoxemia (OR 0.54; 95% CI 0.42, 0.69; p < 0.001) and extreme hyperoxemia (OR 0.50; 95% CI 0.36, 0.71; p < 0.001). The association between hypoxemia and extreme hyperoxemia and worse outcomes was also present with use of "good outcomes" as the outcome variable (discharge to home, rehabilitation, jail, or psychiatric facility, or leaving against medical advice). We conclude that both hypoxemia and extreme hyperoxemia are associated with increased mortality and a decrease in good outcomes among TBI patients.
authors.affiliation: Univeristy of California-San Diego , Department of Emergency Medicine, San Diego, California, USA. davismd@cox.net
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Davis
authors.forename: William
authors.initials: W
authors.lastname: Meade
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Sise
authors.forename: Frank
authors.initials: F
authors.lastname: Kennedy
authors.forename: Fred
authors.initials: F
authors.lastname: Simon
authors.forename: Gail
authors.initials: G
authors.lastname: Tominaga
authors.forename: John
authors.initials: J
authors.lastname: Steele
authors.forename: Raul
authors.initials: R
authors.lastname: Coimbra
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000150:complications / Q000401:mortality* / Q000628:therapy*; D005260:Female; D006801:Humans; D018496:Hyperoxia / Q000209:etiology / Q000503:physiopathology*; D002534:Hypoxia, Brain / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D007049:Iatrogenic Disease / Q000517:prevention & control; D008297:Male; D010100:Oxygen / Q000009:adverse effects; D011379:Prognosis; D020127:Recovery of Function / Q000502:physiology; D012042:Registries; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012720:Severity of Illness Index; D015996:Survival Rate; D013995:Time; D016896:Treatment Outcome
chemical_list: D010100:Oxygen