Target intracranial pressure among patients with aneurysmal subarachnoid hemorrhage: A prospective single-center study

Abstract

Background Management of external ventricular drainage (EVD) among aneurysmal subarachnoid hemorrhage (aSAH) patients remain controversial, and there are no consensus guidelines reporting optimal values of intracranial pressure (ICP). Objective To analyze predictors of delayed cerebral ischemia (DCI) after aSAH and the influence of ICP values on DCI. Methods We prospectively collected patients with aSAH requiring EVD. Predictors of DCI (new CT hypodensities developed within the first 3 weeks not related to others causes) were studied. Vasospasm and brain hypoperfusion were studied with CTA and CTP (RAPID software). Results Among 50 aSAH patients treated with EVD, 21 (42%) developed DCI, while 27 (54%) presented vasospasm. Mean ICP ranged between 2 mmHg and 19 mmHg. On the multivariate analysis, mean ICP (OR = 2, 95% CI = 1.01–3.9, P = 0.04) and mean volume of the hypoperfusion on Tmax delay > 6 (OR = 1.2, 95% CI = 1.01–1.3, P = 0.02) were the only independent predictors of DCI. To predict DCI, Tmax delay > 6 seconds presented the highest AUC (0.956), with a cutoff value of 18 mL showing sensitivity, specificity, PPV, NPV, and accuracy of 90.5% (95% CI = 69%–98.8%), 86.2% (95% CI = 68.4%–96%), 82.6% (95% CI = 65.4%–92%), 92.5% (95% CI = 77%–98%), 88% (95% CI = 75%–95%), respectively. The AUC of the mean ICP was 0.825, and the best cutoff value was 6.7 mmHg providing sensitivity, specificity, PPV, NPV, and accuracy of 71.4% (95% CI = 48%–89%), 62% (95% CI = 42%–79%), 58% (95% CI = 44%–70%), 75% (95% CI = 59%–86%), 66% (95% CI = 51%–79%) for the prediction of DCI, respectively. Conclusion ICP 6 seconds can predict more than 80% of DCI ( Fig. 1 , Fig. 2 ).