Abstract 53: Cerebral Hemodynamic Changes in Patients with Wartime Traumatic Brain Unjury

Abstract

Cerebral vasospasm (VSP) is a frequent complication after aneurysmal and traumatic subarachnoid hemorrhage (SAH) and carries significant morbidity and mortality. Traumatic brain injury (TBI) is associated with the severest casualties from Operation Iraqi Freedom and Operation Enduring Freedom. From Oct. 1, 2008 the US Army Medical Department initiated a transcranial Doppler (TCD) ultrasound service for TBI; included patients were retrospectively evaluated for TCD-determined incidence of posttraumatic cerebral vasospasm and intracranial hypertension after wartime TBI. Patients were identified using a computerized registry and a prospective TCD database maintained in the Sentient NeuroCare Services. TCD recordings of mean cerebral blood flow velocities (CBFV) and Pulsatility Indices of the anterior and posterior circulation vessels were recorded using a 2-MHz transducer (Doppler Box, DWL/Compumedics, USA, Germany/Australia). Comprehensive TCD protocol was applied in all cases: if mean CBFV equaled or exceeded 100 cm/sec., 140 cm.sec and 200 cm/sec the TCD signs of mild vasospasm, moderate vasospasm and severe vasospasm respectively were considered present. 122 patients were investigated with daily TCD studies and comprehensive TCD protocol and published diagnostic criteria for VSP and raised intracranial pressure (ICP) were applied. TCD signs of mild, moderate and severe VSP involving anterior circulation vessels were observed in 71%, 42% and 16% of patients, respectively. TCD signs of mild, moderate and severe VSP involving posterior circulation vessels were observed in 57%, 32% and 14% of patients, respectively. TCD signs of intracranial hypertension were recorded in 43%, eight patients (7%) underwent transluminal angioplasty for post-traumatic symptomatic vasospasm treatment. These findings demonstrate that cerebral arterial VSP and intracranial hypertension are frequent and significant complications of combat TBI, therefore daily TCD monitoring is recommended for their recognition and subsequent management. Acknowledgements. The opinions and views expressed herein belong solely to those of the authors. They are not nor should they be implied as being endorsed by the Uniformed Services University of the Health Sciences, Department of the Army, Department of the Navy, Department of Defense or any other branch of the Federal government of the United States. This paper supported in part, by the US Army Medical Research and Material Command’s Telemedicine and Advanced Technology Research Center (Fort Detrick, MD, USA).