Stump pressure and transcranial Doppler for predicting shunting in carotid endarterectomy.

Abstract

to compare stump pressure (SP) and transcranial Doppler (TCD) with neurologic monitoring during carotid endarterectomy (CEA). one hundred and forty-seven CEAs performed under local anaesthesia. neurologic monitoring and SP were performed in all cases, while mean velocity of the middle cerebral artery (mvMCA) by TCD was done in 140/147 (95%) cases. Shunts were applied in all cases on the basis of neurologic monitoring. The following haemodynamic criteria have been compared to neurologic monitoring: (a) <25 mmHg SP; (b) <50 mmHg SP; (c) < or =10 cm/s mvMCA after carotid occlusion; (d) > or =70 decrease of mvMCA after carotid occlusion. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for each haemodynamic criterion. shunt was used in 18/147 (12.2%) cases. With regards to <25 mmHg SP, < or =50 mmHg SP, < or =10 cm/s mvMCA after carotid occlusion, and > or =70 decrease of mvMCA after carotid occlusion, sensitivity resulted 33, 89, 80 and 80%, respectively. Specificity resulted 96, 82, 97 and 96%, respectively. Positive predictive value resulted 55, 41, 75 and 71%, respectively. Negative predictive value 91, 98, 98 and 98%, respectively. Accuracy resulted 88, 76, 89 and 94%, respectively. none of the haemodynamic criteria by SP and TCD resulted absolutely reliable in predicting the need for carotid shunt.