Computed tomography in the assessment of aneurysmal subarachnoid hemorrhage for functional outcome and delayed cerebral ischemia: a retrospective cohort study.

Abstract

BACKGROUND/OBJECTIVE Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening event with major complications such as delayed cerebral ischemia (DCI) or acute hydrocephalus and poor neurological outcome. DCI occurs most frequently 7 days after aSAH and can last for a prolonged period. The ability to predict these complications would allow the neuro-intensivist to identify patients at risk and select the most appropriate unit for hospitalization. To determine the most predictive radiological scales in grading subarachnoid or ventricular hemorrhage or both for functional outcome at 3 months in a large aSAH population, we conducted a single centre retrospective study in a neurocritical care unit. METHODS A 3-year single-centre retrospective cohort study of 230 patients hospitalized for aSAH was analysed. Initial computed tomography (CT) scans in patients hospitalized for aSAH were blindly assessed using eight grading systems: the Fisher grade, modified Fisher grade, Barrow Neurological Institute scale, Hijdra scale, Intraventricular Hemorrhage (IVH) score, Graeb score, and LeRoux score. We evaluated and compared these radiological scales for the early prediction of DCI, acute hydrocephalus, and poor neurological outcome at 3 months. RESULTS Of 200 patients with aSAH who survived to day 7 and were included for DCI analysis, 39% cases were complicated with DCI. The Hijdra scale was the best predictor for DCI, with a receiver operating characteristic area under the curve (ROCAUC) of 0.80 (95% confidence interval [CI], 0.74–0.85) compared to other scales (Fisher grade 0.52 (95% CI, 0.47–0.59) modified Fisher grade: 0.67 (95% CI, 0.60–0.73); Claassen Scale: 0.66 (95% CI, 0.59–0.72) and BNI Scale: 0.63 (95% CI, 0.56–0.70)). The IVH score was the most effective grading system for predicting acute hydrocephalus, with a ROCAUC of 0.85 (95% CI, 0.79–0.89). In multivariate analysis, the Hijdra scale was the best predictor of the occurrence of DCI (hazard ratio, 1.18; 95% CI, 1.10–1.25). CONCLUSIONS Although these results have yet to be prospectively confirmed, our findings suggest that the Hijdra scale may be a good predictor of DCI and could be useful in daily clinical practice.