Monitoring middle cerebral artery blood velocity during carotid endarterectomy: Padayachee T, Gossling S, Biship RG, et al. Br J Surg 1986;73:98–100

Abstract

The authors report that intraoperative monitoring of middle cerebral blood velocity during carotid endarterectomy has been achieved by means of a transcranial pulsed Doppler ultrasound. The spectral analysis of the blood flow of the middle cerebral artery was correlated with the various stages of the operation. In 19 patients, the authors demonstrate that there is a decrease in the middle cerebral artery blood velocity during carotid clamping. Blood velocity returns to normal or increases with placement of a carotid shunt. In several patients, during back-bleeding of the internal carotid artery, there was a reversal of flow in the middle cerebral artery, suggesting a shunt phenomenon. This is the first report of a study of intraoperative middle cerebral artery blood flow in the literature and it is remarkable for observing intracerebral blood flow changes during the maneuvers of carotid surgery. The authors do not know whether there is any particular significance regarding the changes of blood velocity of the middle cerebral artery. Specifically, it is too early to know whether this technique will be able to select which patients will have cerebral ischemia with carotid clamping since there were no concomitant measurements of cerebral ischemia in this study. Further studies will be needed to determine whether this technique will provide a means of monitoring patients during carotid surgery.