Abstract T MP28: Rigorous Anesthetic Management Protocol for Prevention of Perioperative Stroke in Patients with Intracranial Arterial Stenosis

Abstract

Introduction: Perioperative ischemic stroke results in increased morbidity and mortality. As part of the ongoing EDAS Revascularization for Symptomatic Intracranial Arterial Stenosis (ERSIAS) Trial we have developed a strict anesthesia protocol to prevent fluctuations in patient parameters affecting cerebral perfusion: systolic blood pressure (SBP) and end-tidal CO2 (ETCO2). The hypothesis of this study is that the ERSIAS Anesthesia Management protocol reduces the variability of SBP and ETCO2 compared with a control group of non-stenosis-related vascular neurosurgical interventions. Methods: This is a prospective matched controlled cohort study of patients undergoing EDAS surgery vs. standard neurovascular interventions. ERSIAS patients had strict perioperative management including intentional hypertension and normorcarbia, meticulous fluid balance management, and antiplatelets use. Control patients received routine anesthetic standard of care. Minute-by-minute intra-operative vitals were electronically collected. Heterogeneity of variance test was used to compare variance across groups. Vitals standard deviations were compared with Welch’s tests for unequal variances and mean values were compared with t-test and Wilcoxon rank sums as appropriate. Results: Study population: 10 ERSIAS Trial patients (7 ICASD, 3 MMD) and 11 controls (7 aneurysm, 4 AVM), aged 27 to 75 (mean 51, SD: 15.0), 19 females (91%). There were significant reductions in the variability of SBP and ECO2 in the ERSIAS group below the permutation simulation computed lower boundary decision limit (p<0.05). There was a significant reduction in the SBP SD 31.45 vs. 34.97 (p=0.035), and a trend reduction in ETCO2 SD 2.65 vs. 3.35. As intended, the mean ERSIAS cases SBP and ETCO2 were higher (149.5 vs. 110.9, p<0.0001, and 36.5 vs. 31.2, p=0.0006, respectively). No patients in either group presented strokes. Conclusions: The rigorous ERSIAS peri-operative management protocol was successful in reducing intraoperative fluctuations of blood pressure and ECO2. The protocol was also successful in achieving the intended hypertension and normocarbia.