[A case of silent rupture of a cerebral arteriovenous malformation during laparotomy].

A 52-year-old female, scheduled for rectal cancer resection, had no history of central nervous system abnormality. Anesthesia was maintained with general anesthesia combined with epidural anesthesia. Her only hemodynamic change was a rise in arterial pressure to 140 mmHg just after the start of the operation. However, postoperatively she failed to be aroused and she exhibited a positive Babinski's sign, anisocoria, an absent light reflex and paresis of the left lower extremity. Cerebral vascular accident was suspected and a CT scan revealed a cerebral hematoma which was immediately removed surgically. Upon exploration, abnormal vessels were recognized and we diagnosed an acute rupture of arteriovenous malformation. She fully recovered consciousness immediately after the operation. Her postoperative course was uneventful, except for a residual paresis of the left lower extremity.