REGIONAL CEREBRAL OXYGEN-SATURATION DURING ELECTROCONVULSIVE-THERAPY - MONITORING BY NEAR-INFRARED SPECTROPHOTOMETRY

Electroconvulsive therapy (ECT) increases neuronal energy consumption and alters systemic hemodynamics. We examined the effects of ECT on re gional cerebral oxygen saturation (rSo(2)) using a near-infrared spect rophotometer. Heart rate (HR), mean arterial blood pressure (MAP), and rSo(2) were continuously monitored throughout ECT under general anest hesia in 43 patients. In all subjects, rSo(2) changed in a consistent pattern during ECT, initially decreasing (-9.4% +/- 0.9%) just after a pplication of the electrical current and subsequent increasing (8.7% /- 0.9%) beyond the pre-ECT value. A close correlation was demonstrate d between the increase in rSo(2) and the mean blood pressure after the electrical shock (r(2) = 0.832, P < 0.0001). We conclude that ECT ini tially may increase cerebral metabolic rate of oxygen more than cerebr al blood flow and that rapidly increasing blood pressure transiently m ay overwhelm cerebral pressure autoregulation.