Peripheral Vascular Surgery Society

#19 CORRELATION OF CEREBRALOXIMETRY WITH CAROTID ARTERY STUMP PRESSURES DURING CAROTID ENDARTERECTOMY.

Eugene S. Lee, MD, Dean L. Melnyk, MD, PhD, Michael A. Kuskowski, PhD, and Steven M. Santilli, MD, PhD.

Veterans Affairs Medical Center, University of Minnesota, Minneapolis, MN.

Purpose: In this prospective study, cerebral oximetry and internal carotid artery stump pressures were measured during carotid endarterectomy to assess whether cerebral oximetry correlates with carotid stump pressures.

Methods: Carotid endarterectomy procedures were performed in 20 patients where a cerebral oximeter (Somanetics Inc., Troy, MI) was placed on the ipsilateral forehead preoperatively. Stump pressure data as well as cerebral oximetry readings before and after carotid artery clamping were gathered. The difference between baseline and clamped carotid artery oximetry readings were calculated for each subject and divided by the baseline reading to provide an adjusted measure of percent oximetry change. This normalized percent change in cerebral oximetry readings was then correlated with stump pressure.

Results: Internal carotid artery stump pressures correlated closely with the normalized change in cerebral oximetry readings (r=0.59, p=0.007). Based on the regression analysis, a stump pressure reading of less than 50 mmHg was predicted by at least a 12% drop in cerebral oximetry readings. Based on low intraoperative stump pressure and changes in cerebral oximetry readings, 6 patients underwent arterial shunt placement. There was no morbidity or mortality for the 20 carotid endarterectomy procedures performed.

Conclusion: Carotid endarterectomy can be performed safely with cerebral oximetry as a simple, non-invasive, and reliable alternative to internal carotid artery stump pressure measurements in determining the need for selective carotid artery shunting.

RETURN to Program

Last updated January 1,2000