Visual fixation in the intensive care unit: a strong predictor of post-traumatic amnesia and long-term recovery after moderate-to-severe traumatic brain injury

Abstract

Objective: We examined whether visual fixation at 24h of intensive care unit (ICU) admission is superior to the initial Glasgow Coma Scale (GCS) score to predict PTA duration and long-term TBI recovery. Design: Two-phase cohort study. Setting: Level I trauma ICU. Patients: Moderate-to-severe TBI discharged alive between 2010-2013. Interventions: None. Measurements and Main Results: Presence/absence of visual fixation at 24h of ICU-admission was determined through standard behavioral assessments in 181 TBI patients and compared to the GCS score to predict PTA duration during hospitalization (Phase 1) and performance on the Glasgow Outcome Scale-Extended (GOS-E) 10-40 months after (n=144; Phase 2a). A subgroup also completed a visual attention task (n=35; Phase 2b) and brain magnetic resonance imaging post-TBI (n=23; Phase 2c). Presence/absence of visual fixation at 24h of ICU-admission showed a sensitivity of 84%, a specificity of 82% and an AUC of 0.87 for the prediction of PTA duration. Visual fixation (AUC=0.85) was also found as performant as PTA (AUC=0.81; difference-between-AUC=0.04; 95%CI:-0.03-0.116; p=0.28) for the prediction of GOS-E scores. Conversely, the GCS score was a poor predictor of both PTA and GOS-E. Even when controlling for age/medication/CT scan findings, fixation remained a significant predictor of GOS-E scores (=-0.29, p<0.05). Poorer attention performance and increased regional brain volume deficits were also observed in participants who could not fixate 24h following ICU-admission versus those who could. Conclusions: Visual fixation within 24h of ICU-admission could be as performant as PTA for predicting TBI recovery, introducing a new variable of interest in TBI outcome research.