A retrospective comparison of the use of shunts during carotid endarterectomy.

In this report, compared in retrospect is the incidence of intraoperative stroke among 152 operations performed under hypercarbic general anesthesia without carotid artery shunting, 260 operations performed under both hypercarbia and normocarbia anesthesia with selective shunting based upon internal carotid artery back pressure and 366 operations performed under normocarbia anesthesia with routine carotid artery shunting. Chi-square analysis determined that routine carotid shunting was associated with a significant reduction in the incidence of intraoperative stroke among patients with previous transient ischemic attacks. In addition, both routine shunting and selective shunting, depending upon internal carotid artery back pressure, reduced the incidence of intraoperative stroke among patients with subtotal stenosis of the contralateral internal carotid artery. Considering the safety, simplicity and wide availability of Silastic carotid artery shunts, their routine use during carotid endarterectomy appears advisable in preference to more elaborate and expensive methods of intraoperative cerebral protection.