During the past 5 years, we experienced 481 cases of ruptured intracranial aneurysms. Among these, 45 cases (9.4%) had rebleeding, and especially in 30 cases (6.2%), rebleeding occurred within the first 6 hours after the initial subarachnoid hemorrhage. The analysis of these 30 cases led to the following conclusions.
1) The highest incidence of the rebleeding occurred within 4 hours.
2) Distribution of the aneurysm sites was as follows: anterior cerebral complex (A com), 13 cases; middle cerebral artery (MCA), 8 cases; internal carotid artery (IC), 7 cases; and others, 2 cases.
3) 13 patients incurred rebleeding from such causes as transfer (4 cases), neuroradiological examinations (7 cases), and anesthesia (2 cases), whereas, in 17 cases, there were not any special inducements. In 12 patients rebleeding occurred, even though they were kept on absolute rest, and in6 patients rebleeding occurred in spite of treatment of induced systemic arterial hypotension under 140 mmHg. Thus, since the time factor could precipitate rebleeding, early transfer and operation should be considered for minimizing rebleeding soon after an aneurysm rupture.
4) 3 patients had rebleeding while undergoing angiography within 3 hours after the initial rupture. The greatest care must be taken in dealing with this procedure within the first 3 hours.
5) In our series, 11 of 12 reruptured A com aneurysm cases and 5 of 6 reruptured MCA aneurysms had intracerebral hematoma on initial CT-scan following the first attack. On the other hand, IC aneurysms cases with irregular aneurysmal wall and bleb tend to rebleed. Namely, the risk of rebleeding is very high in cases with intracerebral hematoma.
6) The mortality of these rebleeding cases was high (67%). Barbiturate therapy was considered to be effective for prevention of rebleeding.
