Deep Hypothermia and Surgical Treatment of Intracranial Aneurysms

Sixty-six patients having 67 intracranial aneurysms underwent operation by induced deep hypothermia and extracorporeal circulation by either the open-chest or the closed-chest method at the Mayo Clinic in a five-year period, 1960 to 1965. One patient was killed by her demented husband and 15 patients died of unsuccessful operation. Factors unrelated to the extracorporeal circulation technique per se contributed to death in more than half of the cases. Deletion of these reduced the overall mortality to about 14.5%. The increased operating time required by deep hypothermia and circulatory arrest did not appear to increase the postoperative complications. Alteration in blood-clotting characteristics constituted the major deterrent to deep hypothermia. The closed-chest method of perfusion is preferable.