Trajectories of Neurologic Recovery after Traumatic Brain Injury

BACKGROUNDLittle is known about the trajectory over time of neurologic recovery after traumatic brain injury (TBI). We sought to determine long-term changes in neurologic status after prehospital clinical trial interventions for acute TBI. METHODSWe used data from the Resuscitation Outcomes Consortium Hypertonic Saline (ROC HS) TBI Trial. The trial included adult TBI, with Glasgow Coma Scale (GCS)[≤]8 and excluded those with shock (systolic blood pressure (SBP)[≤]70, or SBP 71-90 with HR[≥]108). The primary outcome was Glasgow Outcome Scale-Extended (GOS-E; 1=dead, 8=no disability) determined at: a) hospital discharge and b) 6-month follow-up. We analyzed changes in GOS-E between hospital discharge and 6-month follow-up by examining median changes with exact 95% confidence intervals (CI), mean changes with bootstrapped 95% CIs and Sankey graphs. We repeated the analysis for the high acuity subset of patients undergoing prehospital advanced airway insertion. RESULTSAmong 1,279 TBI subjects included in the analysis, GOS-E categories at hospital discharge were: favorable (GOS-E 5-8) 220 (17.2%), unfavorable (GOS-E 2-4) 664 (51.9%), dead (GOS-E 1) 321 (25.1%), missing 74 (5.8%). GOS-E categories at 6-month follow-up were: favorable 459 (35.9%), unfavorable 279 (21.8%), dead 346 (27.1%), missing 195 (15.2%). Among initial TBI survivors with complete GOS-E, >96% followed one of three neurologic recovery trajectories: 1) favorable to favorable (20.0%), 2) unfavorable to favorable (40.3%), and 3) unfavorable to unfavorable (36.0%). Few patients deteriorated from favorable to unfavorable neurologic status and there were few additional deaths. CONCLUSIONNeurologic recovery after TBI follows distinct trajectories. Among those with TBI and unfavorable neurologic status at hospital discharge, almost half will improve to favorable neurologic status at six months. Among those with favorable neurologic status at discharge, very few worsen to unfavorable neurologic status or death at six months. These findings have important implications for TBI clinical care, research and trial design.