Routine or selective carotid artery shunting for carotid endarterectomy (and different methods of monitoring in selective shunting)

Abstract

Background: Temporary interruption of blood flow during carotid endarterectomy can be avoided by using a shunt across the clamped section of the carotid artery. This may improve outcome.

Objectives: The objective of this review was to assess the effect of routine versus selective shunting during carotid endarterectomy, and to assess the best method for selecting patients for shunting.

Search strategy: We searched the Cochrane Stroke Group trials register, Medline (1966 to 1994), Embase (1980 to 1995) and Index to Scientific and Technical Proceedings (1980 to 1994). We handsearched Annals of Surgery (1981 to 1995), British Journal of Surgery (1985 to 1995), European Journal of Vascular Surgery (1988 to 1995) and World Journal of Surgery (1978 to 1995).

Selection criteria: Randomised and quasi-randomised trials of routine shunting compared with no shunting, and trials that compared different shunting policies in patients undergoing carotid endarterectomy.

Data collection and analysis: Two reviewers independently applied the inclusion criteria. The data were extracted by one reviewer and double-checked. Trial quality was assessed.

Main results: Three trials were included. Two trials involving 590 patients compared routine shunting with no shunting. The other trial involving 131 patients compared shunting with a combination of electroencephalographic and carotid pressure measurement, with shunting by carotid pressure measurement alone. Allocation was adequately concealed in one trial, and one trial was quasi-randomised. Analysis was by intention-to-treat where possible. For routine versus no shunting, there was no significant difference in the rate of all stroke, ipsilateral stroke or death up to 30 days after surgery, although data were limited. There was no significant difference between the risk of ipsilateral stroke in patients selected for shunting with the combination of electroencephalographic and carotid pressure assessment compared to pressure assessment alone, although again the data were limited.

Reviewer's conclusions: The data presently available are too limited to either support or refute the use of routine or selective shunting in carotid endarterectomy. Large scale randomized trials using no shunting as the control group are required. No one method of monitoring in selective shunting has been shown to produce better outcomes.