ORIGINAL PAPER
Predictors of postoperative mortality in ruptured aneurysms of internal carotid artery

Background and purpose : An analysis of predictors of mortality in patients with ruptured intracranial aneurysm is an important aspect in the assessment of outcome. The aim of the study was to analyse factors determining mortality risk after the surgical treatment of ruptured internal carotid artery (ICA) aneurysm.

Material and methods : This study comprised 242 patients operated on between 1997 and 2006 in the Neurosurgery Department of the Medical University Hospital in Gdansk, Poland. Multivariate logistic regression, ROC curves (for model assess­ment as a mortality classifier) and population attributable risk for contribution of individual factor mortality explanation were used to assess factors related to in-hospital mortality.

Results : 14.9% of patients died postoperatively. In univariate analysis, increased risk of death was related to the Glasgow Coma Scale score, WFNS score, Hunt-Hess and Fisher grade, preoperative neurological deficit, delayed cerebral ischaemia (DCI), trapping and bypass operative method. Multivariate analysis revealed two independent predictors of in-hospital mortality: DCI and Hunt-Hess grade. 91% of mortality risk was attributed to grade 4 or 5 in Hunt-Hess scale and DCI. The dominant predictor of survival was the Hunt-Hess scale. Increase by one grade in the Hunt-Hess scale resulted in two-fold increase of in-hospital mortality risk.

Conclusions : Postoperative mortality after ICA aneurysm rupture is determined by clinical status at admission and the occurrence of DCI.