Out-of-hospital endotracheal intubation and outcome after traumatic brain injury

Study objective: Previous studies disagree about the effect of out-of-hospital endotracheal intubation on traumatic brain injury. This study compares the effects of out-of-hospital endotracheal intubation versus emergency department (ED) endotracheal intubation on mortality and neurologic and functional outcome after severe traumatic brain injury. Methods: From the 2000 to 2002 Pennsylvania Trauma Outcome Study (a registry of all patients treated at trauma centers in the Commonwealth of Pennsylvania), adult patients with head/neck Abbreviated Injury Scale score of 3 or greater and undergoing out-of-hospital endotracheal intubation or ED endotracheal intubation were included. Transferred patients were excluded. The primary outcome was death (on hospital discharge). The secondary outcomes were neurologic (good versus poor, inferred from discharge to home versus long-term care facility) and functional outcome (determined from a Functional Impairment Score). The key exposure was endotracheal intubation (out-of-hospital endotracheal intubation versus ED endotracheal intubation). Using multivariate logistic regression, odds estimates for out-of-hospital endotracheal intubation were adjusted using age, sex, head/neck Abbreviated Injury Scale score, Injury Severity Score, mechanism of injury (penetrating versus blunt), admission systolic blood pressure, mode of transport (ground only versus helicopter or helicopter + ground), and the use of out-of-hospital neuromuscular blocking agents. A propensity score adjustment accounted for the potential effects of preexisting conditions, inhospital complications, and social factors (drug and alcohol use, race, and insurance coverage). Results: There were 4,098 patients with head/neck Abbreviated Injury Scale score of 3 or greater who received either out-of-hospital endotracheal intubation (n=1,797, 43.9%) or ED endotracheal intubation (n=2,301, 56.1%). Adjusted odds of death were higher for out-of-hospital endotracheal intubation than ED endotracheal intubation (odds ratio [OR] 3.99; 95% confidence interval [CI] 3.21 to 4.93). Out-of-hospital endotracheal intubation was associated with an increased adjusted odds of poor neurologic outcome (OR 1.61; 95% CI 1.15 to 2.26), moderate or severe functional impairment (Functional Impairment Score 6 to 15; OR 1.92; 95% CI 1.40 to 2.64), and severe functional impairment (Functional Impairment Score 11 to 15; OR 1.80; 95% CI 1.29 to 2.52). Conclusion: Out-of-hospital endotracheal intubation was associated with adverse outcomes after severe traumatic brain injury. The implications for current clinical care remain undefined.