Prognostic significance of altered cerebral blood flow velocity in acute head trauma

From July 1992 to January 1993, 31 patients with acute closed head injuries underwent blood flow velocity (BFV) measurement in the middle cerebral artery by transcranial Doppler ultrasound. Eighteen patients had abnormal changes of BFV (group A) and 13 patients had normal BFV (group B). In group A, there were eight deaths (44%), and the Glasgow Outcome Scale score was 2.6 ± 0.4 (mean ± SEM). On admission, 14 group A patients had decreased BFV, including nine patients with evidence of early cerebral circulatory arrest (CCA). During hospitalization, eight group A patients were diagnosed with global hyperemia, including two patients who had early CCA. Another six, in group A, had ultrasound recordings consistent with vasospasm, and three of these six also experienced early CCA. The remaining four patients in group A had persistently low BFV, progressing from early CCA. In group B, there were two deaths (15%) and the mean Glasgow Outcome Scale score was 4.0 ± 0.5. Group A had higher mortality (Fisher's exact test, p = 0.128) and a significantly higher rate of unfavorable functional outcome than group B. To evaluate the prognostic significance of these BFV changes, group A was subdivided into global hyperemia, vasospasm and early CCA subgroups. Both the vasospasm and early CCA subgroups had significantly lower Glasgow Coma Scale scores on admission and a higher rate of unfavorable functional outcomes than group B. All five survivors with vasospasm and/or early CCA showed ischemic morbidity on follow-up cranial computed tomography; though those with global hyperemia did not. There were no significant differences in the Glasgow Coma Scale score on admission, mortality or functional outcome between global hyperemia patients and group B patients. Global hyperemia may represent a recovery stage of impaired cerebral hemodynamics. This stage may occur transiently and has no major impact on morbidity or mortality. Vasospasm and early CCA may be closely related to ischemic complications, and may provide clinical information for selecting appropriate therapy in acute head trauma.