NON-INVASIVE PERIOPERATIVE MONITORING OF CAROTID ENDARTERECTOMY

Doppler ultrasound and supraorbital photoplethysmography were used to screen 79 patients undergoing 87 carotid endarterectomies in the perioperative period. Supraorbital photoplethysmography permitted continual monitoring of ophthalmic artery flow dynamics throughout the operation on 14 patients. The ratio of supraorbital pulse amplitude during and prior to carotid clamping correlated well with the carotid back (stump) pressure (R = 0.87, P < 0.001). A sterile Doppler probe permitted assessment of the integrity of carotid endarterectomy during the operation. Postoperative screening by Doppler ultrasound identified asymptomatic residual obstruction in six external carotid arteries (6.9%) and four internal carotid arteries (3.4%). Noninvasive perioperative screening of patients undergoing carotid endarterectomy provides useful information to assess the efficacy of this reconstructive procedure. © 1979.