Abstract
A 52--year-old woman underwent operation for the removal of the cerebellar hemisphere cyst under general anesthesia with modified neuroleptanesthesia. Immediately after the absorption of tumor contents, blood pressure fell down. We succeeded the elevation of blood pressure with ephedrine and norepinephrine. Some causes of this hypotension were suggested, but we were not convinced what was the cause. So that we emphasize the importance of monitoring, for example ECG, continuous intraarterial blood pressure recording, intermittent arterial blood gases analysis, continuous auscultation of the heart sounds by esophageal stethoscope, Doppler ultrasonic detector and so forth.
