Hemoglobin Drop is Associated with Early Post-operative Stroke Following Revascularization Surgery for Moyamoya Disease

Background: Postoperative stroke is a potentially devastating neurological complication following surgical revascularization for Moyamoya disease. We sought to evaluate whether peri-operative hemoglobin levels were associated with the risk of early post-operative stroke following revascularization surgery in adult Moyamoya patients. Methods: Adult patients having revascularization surgeries for Moyamoya disease between 1999-2022 were identified through single institutional retrospective review. Logistic regression analysis was used to test for the association between hemoglobin drop and early postoperative stroke. Results: In all, 106 revascularization surgeries were included in the study. A stroke occurred within 7 days after surgery in 9.4% of cases. There were no significant associations between the occurrence of an early postoperative stroke and patient age, gender, or race. Mean postoperative hemoglobin drop was greater in patients who suffered an early postoperative stroke compared with patients who did not (2.3±1.1 g/dL vs. 1.3±1.1 g/dL, respectively; P =0.034). Patients who experienced a hemoglobin drop post-operatively had 2.03 times greater odds (95% confidence interval, 1.06-4.23; P =0.040) of having a stroke than those whose hemoglobin levels were stable. Early postoperative stroke was also associated with an increase in length of hospital stay ( P <0.001), discharge to a rehabilitation facility ( P =0.014), and worse modified Rankin scale at 1 month ( P =0.001). Conclusion: This study found a significant association between hemoglobin drop and early postoperative stroke following revascularization surgery in adult patients with Moyamoya disease. Based on our findings, it may be prudent to avoid hemoglobin drops in Moyamoya patients undergoing surgical revascularization.