An Association Between Prophylactic Hypervolemia-Augmented Blood Pressure and Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage Who Underwent Delayed Clipping

Abstract

BackgroundThe prior trials investigating triple-H therapy for preventing delayed cerebral ischemia (DCI) enrolled patients with aneurysmal subarachnoid hemorrhage (aSAH) who underwent early aneurysm therapy within three days. However, surgical clipping might be performed during 4-7 days that high incidence cerebral vasospasm is likely. We examined effects of hypervolemia-augmented blood pressure (HV-ABP) protocol on DCI prevention when clipping was delayed. MethodsThe study enrolled aSAH patients hospitalized during 2013-2019 who underwent clipping 4-7 days after rupture in a university hospital in Thailand. DCI and secondary outcomes were compared among patients, who achieved the HV-ABP protocol (3-5L/day fluid intake and 140-180mmHg SBP maintained for 72 hours postoperatively) and those who did not. The intervention-outcome associations were estimated using logistic regression for the whole group and a patient sub-group with similar propensity scores (PS) for protocol achievement. Results177 aSAH patients were clipped 4-7 days after rupture, 97 patients (54.8%) achieved the HV-ABP protocol, while 80 patients (45.2%) did not. 122 patients with one-to-one PS matching reduced the originally unequal patient characteristics. The observed DCI was lower in patients with protocol-achieved (8.3%) than in their non-achieved counterparts (22.5%). This resulted in an association with the HV-ABP intervention with adjusted odds ratios of 0.201 (95% confidence interval, 0.066-0.613) in the whole sample and 0.228 (0.065-0.794) in the PS-matched sub-sample. No statistically significant differences in the secondary outcomes were found. ConclusionsAchieving the targets recommended in the HV-ABP protocol was associated with reducing the DCI incidence in patients with aSAH who underwent delayed clipping.