Correlation of transcranial Doppler sonography findings with timing of aneurysm surgery.

Thirty-six patients with a proven first subarachnoid hemorrhage (SAH) from a ruptured supratentorial aneurysm were subjected to repeated transcranial Doppler sonography assessments. Eighteen individuals (Group A) were operated on within 48 hours, while the other 18 (Group B) had surgery between 49 and 96 hours after SAH. The patients represented two clinically comparable groups. In the first 72 hours post-SAH, no increased flow velocities suggestive of arterial narrowing or vasospasm were recorded. There was no significant difference in preoperative flow velocities between the groups. Postoperative flow velocities were significantly lower in patients operated on within 48 hours (p less than 0.001). Two patients, who had surgery on Day 4 post-SAH and who showed the highest recorded postoperative flow velocities, died from cerebral vasospasm and infarction. The results favor a referral system which enables early surgical intervention not only to prevent rebleeds but also aimed at reducing delayed ischemic dysfunction.