A Propensity Score Analysis of the Impact of Invasive Intracranial Pressure Monitoring on Outcomes after Severe Traumatic Brain Injury.

Abstract

Although a recent clinical trial (BEST TRIP) demonstrated no improvement in outcomes with invasive intracranial pressure (ICP) monitoring (ICPM) following severe traumatic brain injury (TBI), its generalizability has been called into question. In several global settings ICPM is not the standard of care and is used at the discretion of the attending neurosurgeon. Our objective was to determine the impact of ICPM on mortality and 6-month functional outcomes following severe TBI. The setting was a referral trauma center with 36 intensive care unit (ICU) beds and 300-600 TBI admissions per year. During a 2-year period data were prospectively entered into a severe TBI registry. Patients with severe TBI aged >12 years meeting Brain Trauma Foundation (BTF) criteria for ICPM were included in the study. Outcomes of interest were in-hospital mortality and poor 6-month functional outcome defined as Glasgow Outcome Scale (GOS) score of 3 or lower. A propensity score based analysis incorporating known predictors of outcome in TBI was utilized to examine the impact of ICPM on outcomes. Of 1345 patients meeting study criteria 497 (37%) underwent ICPM. In-hospital mortality was 35% (471/1345). Of 454 patients for whom 6-month outcome was available, 161 (35%) suffered a poor functional outcome. Following propensity score analysis ICPM use was associated with an 8% (p = 0.002) decrease in mortality but no significant effect (p = 0.2) on functional outcome. The use of ICPM following severe TBI was associated with decreased in-hospital mortality. Further clinical trials of ICPM in TBI may be warranted.