Prospective Evaluation of Post-Traumatic Vasospasm and Post-Injury Functional Outcome Assessment: Is Cerebral Ischemia Going Unrecognized in Patients with Traumatic Brain Injury?

Abstract

Background: Secondary injury processes such as posttraumatic vasospasm (PTV) play a critical role in the development of cerebral ischemia/infarction after traumatic brain injury (TBI). The objectives of this study were to evaluate the incidence of cerebral vasospasm in patients with moderate to severe TBI and to assess post-injury functional outcome. Study Design: A prospective observational study was conducted in patients with moderate and severe blunt TBI. Transcranial Doppler (TCD) ultrasound was performed within the first 72 hours and then daily for up to 7 days. Patient characteristics and outcome data including functional outcome as assessed by the Extended Glasgow Outcome Scale (GOS-E) were collected and compared between patients with and without PTV. Results: Twenty-three patients met our inclusion criteria. While there was a 47.8% incidence of vasospasm as detected by TCD, there was no significant difference in hospital LOS or mortality between patients with and without PTV. Of the two patients with PTV who died, both had a cerebral infarct or cerebral ischemia. In evaluating overall GOS-E among patients with a cerebral focal injury, patients with PTV had a significantly higher GOS-E score when compared to patients without PTV (8.0 vs. 6.8, p = 0.01). Conclusions: The high incidence of PTV and the role of clinically significant vasospasm after TBI remain unclear. While functional outcome was better in patients with a focal injury and vasospasm, patients who died had cerebral ischemia or infarction. We hypothesize that there is an interaction between impaired cerebral autoregulation, PTV and poor outcomes in patients with TBI.