Comparison of Outcomes of Severe Traumatic Brain Injury in 36,929 Patients Treated with or without Intracranial Pressure Monitoring in a Mature Trauma System

Abstract

Severe traumatic brain injury (TBI) remains a major cause of morbidity and mortality with mortality rates reaching 35%. Intracranial pressure (ICP) monitoring is used to prevent secondary brain injury and death. However, while the association of elevated ICP and worsened outcomes is accepted, routine ICP monitoring has been questioned after the publication of several studies including the Benchmark Evidence from South American Trials: Treatment of Intracranial Pressure trial. We examined whether severe TBI patients in the trauma system of Pennsylvania fared better with or without ICP monitoring. We conducted a statewide retrospective analysis and included all TBI patients >18 years with an admission Glasgow Coma Scale (GCS) <9 from January 2000 through December 2017. The primary outcome was mortality. Secondary outcomes examined were intensive care unit length of stay (LOS) and discharge functional independence measure (FIM). A total of 36,929 patients matched our inclusion criteria and were included in the analysis. Of those, 6025 (16.3%) had ICP monitor placement. Mean ICU LOS was significantly higher in ICP-monitored patients (13.1 ± 11.6 days vs. 6.0 ± 10.8 days, P < 0.0001). Increasing age was a significant predictor of death (P < 0.0001). Mean FIM scores at discharge were significantly higher in patients without an ICP monitor (16.21 ± 4.91 vs. 9.53 ± 5.07, P < 0.0001). When controlling for injury severity score, GCS, age, and craniotomy, ICP monitoring conferred a hazard ratio of 0.85 (χ2= 32.63, P < 0.0001), a 25% reduction of in-hospital mortality compared with non-ICP-monitored patients. We found that ICP-monitored patients had a lower risk of in-hospital mortality. Our findings support the use of ICP monitors in eligible patients.