The incidence of intraoperative aneurysm rupture (IAR) was studied in
a consecutive personal series of 222 patients operated on for a ruptur
ed intracranial aneurysm. In 77 patients subjected to early surgery (o
peration within 72 h after rupture) IAR was 40.2% and in 145 patients
with surgery after 72 h IAR was 20.7%. The mortality and severe morbid
ity (GOS grade 4 and 5) were 2.6% in the early surgery group, 7.6% in
the late surgery group, and 5.85% in the total series despite the fact
that there was a significantly higher incidence of IAR in the early s
urgery group. Aneurysms arising from the anterior cerebral artery (ACA
) or anterior communicating artery (ACoA) appeared more prone to IAR-3
6.9 versus 18.6 and 23.2%-than aneurysms at other locations. There was
no correlation between incidence of IAR and preoperative Hunt and Hes
s grade [8]. IAR affected final outcome only when it occurred prematur
ely during introduction of anesthesia or during opening of the dura. I
n conclusion, although IAR occurs more frequently when surgery is unde
rtaken in the early stage after rupture, this complication is in exper
ienced hands not necessarily associated with an increased risk for an
unfavorable outcome.