Both the risk of rerupture of the aneurysm and some of the secondary problems that arise because of blood in the subarachnoid space can be obviated by early obliteration of the aneurysm. Because of the changes in water balance and the risk of delayed stroke from vasospasm, there has been an emphasis on early volume expansion and sodium repletion by the intravenous infusion of crystalloids. As Solomon and Fink have pointed out, this can be accomplished without fear of aneurysmal rupture if blood pressure is allowed to rise only minimally. Of course, fluid replacement and a modest elevation of blood pressure become completely safe if the aneurysm has been surgically occluded. Because of the current approach of ablating the aneurysm early, the previously popular use of antifibrinolytic agents as a means of impeding lysis of the clot at the site of aneurysmal rupture has been generally abandoned. Repeated drainage of the CSF by lumbar puncture is also no longer practiced as a routine. One lumbar puncture is generally carried out for diagnostic purposes if the CT is inconclusive; thereafter, spinal fluid drainage is performed only for the relief of intractable headache or to detect recurrence of bleeding. As mentioned earlier, patients with stupor or coma who have massive hydrocephalus often benefit from decompression of the ventricular system. This is accomplished initially by external drainage and may require permanent shunting if the hydrocephalus returns. The common practice of draining milder degrees of hydrocephalus has not been proven to be helpful. Some risk may attend rapid removal of CSF by this method or lumbar puncture but some centers still undertake it. The risk of infection of the external shunt tubing is high if it is left in place for much more than 3 days. Replacement with a new drainage tube, preferably at another site, reduces this risk.
Obliteration of the aneurysm The current approach is to operate or eliminate the aneurysm by endovascular means early, within 24 h if possible, for patients who are in Hunt and Hess grades I and II, and then to increase intravascular volume and maintain normal or above-normal blood pressures. This precludes rebleeding, with its high mortality, and ameliorates the second cause of morbidity, stroke from vasospasm.
The timing of surgery or endovascular treatment for grade III patients is still controversial but if their medical condition allows, they, too, probably benefit from the same early and aggressive approach. In grade IV patients, the outcome is generally dismal, no matter what course is taken, but we have usually counseled against early operation; some neurosurgeons disagree. The insertion of ventricular drains into both frontal horns has occasionally raised a patient with severe hydrocephalus to a better grade and facilitated early operation. In the hands of experienced anesthesiologists and cerebrovascular surgeons, the operative mortality, even in grades III and IV patients, has now been reduced to 2 to 3 percent.