Cortical blood flow response to hypercapnia during anaesthesia in Moyamoya disease

Abstract

Cortical blood flow (CoBF) was measured continuously by the laser-Doppler method to evaluate the effect of hypercapnia on cortical blood flow during ten surgical procedures in ten young patients (mean ± SD 9.3 ± 6.4 yr) with Moyamoya disease. The CoBF was 42.8 ± 13.4 (ml·100 g-1. min-1) during normocapnia (PaCO2 = 39.0 ± 2.4 mmHg), and 38.7 ± 14.4 during hypercapnia (PaCO2 = 47.1 ± 2.5 mmHg). There was a decrease in CoBF with hypercapnia (P < 0.05) so that the normal CoBF response to hypercapnia was impaired during surgery in the patients with Moyamoya disease. He concluded that patients with Moyamoya disease have a precarious cerebral circulation and hypercapnia may be detrimental to the cortical circulation. This suggests that normocapnia is preferable to hypercapnia in patients with Moyamoya disease during anaesthesia. © 1993 Canadian Anesthesiologists.