Testing of potential biomarkers of cerebral ischemia and vasospasm in patients with cerebral aneurysm surgery

Abstract

Biomarkers for the prediction of vasospasm and delayed cerebral ischemia in patients with a ruptured cerebral aneurysm could be helpful. In this prospective clinical study, endothelin-1, lactate, pCO2, and pO2 were measured in arterial and internal jugular vein blood before, during and after surgical treatment of a cerebral aneurysm, and were tested as potential predictors of neurologic outcome in patients. Forty-one patients were enrolled in the study, 23 of them were operated on after aneurismal rupture with development of subarachnoid hemorrhage (SAH) and 18 patients were operated on for a nonruptured aneurysm. All of the involved patients survived. There was no difference in neurologic outcome between those operated on with a ruptured or nonruptured aneurysm. Endothelin-1 and lactate concentrations as well as pO2 and pCO2 from arterial and venous blood samples and their venoarterial difference did not differ between groups with and without an aneurismal rupture. Venoarterial difference of endothelin-1 concentrations on the day after surgery significantly differed between the groups with favorable and nonfavorable neurologic outcome. Other variables did not show a statistically significant difference. Significant correlation was found between endothelin-1 and lactate concentrations, suggesting involvement of the same pathophysiological process. Another interesting finding was lower arterial and venous pCO2 in patients with lower initial Glasgow Coma Scale (GCS) score and higher Hunt Hess score in the phase after extubation. We can conclude that the measured biochemical parameters did not show sufficient predictive power to be useful for prediction of cerebral vasospasm and neurologic outcome in everyday clinical practice. However, some correlations that do exist between them suggest involvement of the same pathophysiological process.