Cerebral Arterial Compliance in Traumatic Brain Injury

The main role of the cerebral arterial compliance (cAC) is to maintain the stiffness of vessels and protect downstream vessels when changing cerebral perfusion pressure. The aim was to examine the flexibility of the cerebral arterial bed based on the assessment of the cAC in patients with traumatic brain injury (TBI) in groups with and without intracranial hematomas (IHs).

We examined 80 patients with TBI (mean age, 35.7 ± 12.8 years; 42 men, 38 women). Group 1 included 41 patients without IH and group 2 included 39 polytraumatized patients with brain compression by IH. Dynamic electrocardiography (ECG)-gated computed tomography angiography (DHCTA) was performed 1-14 days after trauma in group 1 and 2-8 days after surgical evacuation of the hematoma in group 2. Amplitude of arterial blood pressure (ABP), as well as systole and diastole duration were measured noninvasively. Transcranial Doppler was measured simultaneously with DHCTA. The cAC was calculated by the formula proposed by Avezaat.

The cAC was significantly decreased (p < 0.001) in both groups 1 and 2 compared with normal data. The cAC in group 2 was significantly decreased compared with group 1, both on the side of the former hematoma (р = 0.017).

The cAC in TBI gets significantly lower compared with the conditional norm (p < 0.001). After removal of the intracranial hematomas, compliance in the perifocal zone remains much lower (р = 0.017) compared with compliance of the other brain hemisphere.