Risk factors for post-carotid endarterectomy hematoma formation

Purpose: To identify risk factors for post-carotid endarterectomy (CEA) hematoma formation and establish the incidence of this complication at The Ottawa Hospital - Civic Campus (TOH-CC). Methods: A chart review of all patients who underwent CEA at TOH-CC from January 1, 1996 to December 31, 1997 was completed. Identified cases of post-CEA wound hematoma were entered into a case-control study using age and sex-matched controls from within the cohort. These matched pairs were assessed for 31 potential risk factors including demographic details, co-existing medical conditions, preoperative medications, intraoperative management, and postoperative parameters. Risk factors associated with post-CEA hematoma with P < 0.05 were entered into a backward step-wise logistic regression model for multivariate analysis. Results: Charts from 249 patients were reviewed and 29 cases of post-carotid endarterectomy hematoma were identified (12% incidence). Six of the initial 31 potential risk factors emerged as univariate predictors of post-CVA hematoma formation (P < 0.05): general anesthesia, carotid shunt placement, intraoperative hypotension, non-reversal of heparin, neurosurgery service, and preoperative aspirin use. Following logistic regression only non-reversal of heparin, intraoperative hypotension, and carotid shunt placement were identified as multivariate predictors of post-CEA hematoma formation. More time was spent in critical care settings (ICU/PACU) (P < 0.01) and there was increased perioperative mortality (P = 0.04) within the hematoma group. Conclusions: Post-CEA hematoma formation is associated with increased morbidity and mortality. Non-reversal of heparin, intraoperative hypotension, and carotid shunt placement are multi-variate predictors of post-CEA hematoma formation.