Analysis of factors affecting complications of carotid ligation.

A study of 156 patients subjected to common carotid ligation in the treatment of head and neck carcinoma was made to investigate the influence of selected factors on cerebral complications. In the analysis complications were grouped as death or coma; death, coma, hemiplegia or monoplegia; and transitory cerebral symptoms. Primary independent variables included method of occlusion (abrupt, gradual); duration of occlusion; and collateral circulation via the external carotid artery (intact, ligated external carotid artery). Death or coma occurred in 24 cases (15.4%) and complications including death, coma, hemiplegia or monoplegia occurred in 47 cases (30.1%). Although no statistically significant difference between abrupt and gradual occlusion cases was noted, the incidence of cerebral complications was significantly lower for the group with gradual carotid occlusions performed over 13 days (6.3%) than for those with abrupt occlusions or gradual occlusions performed in less than five days. The incidence of death or coma following carotid artery occlusion was 10.5% in cases with an intact external carotid artery, as against 25.5% in those with a ligated external carotid artery, a statistically significant difference. Cerebral complications occurred within 48 hours after carotid occlusion in 35 of 47 cases (74.5%) in which complications developed. In the remaining 12 cases (25.5%) complications developed after 48 hours. There was no difference between abrupt and gradual occlusion cases in the incidence of complications after 48 hours.