A comparison of early versus delayed surgery for ruptured intracranial aneurysms - abstract

ABSTRACT

The timing of surgical clipping for ruptured intracranial aneurysms has been a subject of debate for many years. Initial attempts at early surgery (within 24-72 hours) had disastrous results and led to the standard practice of delaying surgery for 7-10 days. The use of antifibrinolytic agents during this waiting period was shown to decrease the incidence of rebleeding but also seemed to cause increased frequency of ischaemic deficits and hydrocephalus. With the refinement of microneurosurgical techniques, early surgery for intracranial aneurysms underwent a rebirth in many centres over the last few years. This paper presents the experiences with aneurysm surgery at the Neurosurgical Unit Halifax, Nova Scotia over the four-year period 1984-1987. Ruptured aneurysms lead to subarachnoid haemorrhage in over 50 percent of the cases, arteriovenous malformations comprised 10 percent, and subarachnoid haemorrhage with normal angiography 25 percent of the total cases. During the period under review 25 patients presented with ruptured vertebrobasilar aneurysms and 211 patients presented with ruptured supratentorial aneurysms. The latter group form the basis for comparing results of early vs. delayed clipping for ruptured aneurysms. Despite the fact that the series comprised a consecutive, unmatched group of patients without any attempt at randomization, there were striking similarities in the mean ages, sex distribution and distribution of aneurysms at the various sites in the two groups being compared. Sixty-nine patients presented in good clinical condition after aneurysmal subarachnoid haemorrhage (Hunt & Hess Grades I and II). Twenty-nine patients (mean age 44.5 years) underwent early surgery and 40 (mean age 45 years) had delayed surgery. Despite the higher rebleed rate in the delayed group (12.5 percent vs. 0 percent) there was no statistically significant difference in the eventual outcome between the two groups (mortality rate and the quality of survival). Eighty-five of the patients had excellent outcomes. However, the length of hospital stay was significantly shorter in the patients operated on early (17 days vs. 30 days). Symptomatic vasospasm (40 percent) and hydrocephalus (10 percent) occurred with similar frequencies in both groups. Fifty-two patients presented in poor clinical condition after aneurysmal subarachnoid haemorrhage (Hunt & Hess Grades III and IV). Twenty-three patients (mean age 49.5 years) had early surgery and 29 patients (mean age 53 years) had delayed surgery. The mortality rate (approximately 25 percent) was similar in both groups. Rebleeding was the culprit in the delayed group (24 percent) whereas the surgical mortality was 26 percent in the early group. There was an equally high incidence of symptomatic vasospasm and hydrocephalus in both groups. The quality of survival was better in the early group but achieved statistical significance only in the number of patients making "excellent" recoveries (43 percent vs. 17 percent). The numbers of patients however were small. Aggressive treatment of acute hydrocephalus by ventricular drainage played a large part in improving the clinical status prior to surgery in the early group. As with previous studies (including a large co-operative series), we have been unable to show a really convincing advantage of early aneurysm surgery over delayed surgery if mortality rate and quality of survival are used as the basis of comparison. Clearly, a large scale randomized trial would have to be launched to answer this question conclusively. To answer the criticisms of ardent proponents of delayed surgery, however, we have confirmed that early surgery provides at least as good results. We have not found early surgery technically more difficult. It allows removal of large collections of subarachnoid blood and aggressive treatment of cerebral vasospasm and hydrocephalus and at the same time prevents rebleeding from the aneurysm. We feel early surgery will become more frequently used as newer methods of preventing cerebral vasospasm are discovered. The implications of our experiences to the situations that obtain in the Caribbean will be discussed (AU)