External carotid artery shunting during carotid endarterectomy: An alternative for cerebral protection?

Objectives: to assess the application of external carotid artery (ECA) shun ting in cerebral protection during carotid endarterectomy (CEA). Design: prospective study. Materials and Methods: the study comprised 137 consecutive patients who und erwent CEA under locoregional anaesthesia. Transcranial Doppler was used to monitor the mean velocity of the middle cerebral artery (mv-MCA): (1) befo re carotid clamping; (2) after clamping both the common and external caroti d arteries; (3) after clamping the internal carotid artery alone ("ECA test "). The decision to shunt was based on the occurrence of neurological defic it during carotid clamping. If the ECA test revealed mv-MCA approaching the pre-clamping values ECA shunting was used, whereas the remaining patients in need of a shunt had a standard internal carotid artery (ICA) shunt. Results: shunting was necessary in 12/137 cases (9%). The ECA test indicate d that in four cases -3% of the whole series or 33% of the shunted cases. I n these four patients ECA shunting reversed the neurological deficit, and C EA was successfully performed without any complications. Conclusions: ECA shunting could be considered as an alternative to standard ICA shunting. Suitable cases can be identified on the basis of the ECA tes t.