Improved survival after aneurysmal subarachnoid hemorrhage: review of management during a 12-year period

Abstract

Object. Based on the concept that unfavorable clinical outcome after aneurysmal subarachnoid hemorrhage (SAH), to a large extent, is a consequence of all ischemic insults sustained by the brain during the acute phase of the disease, management of patients with SAH changed at the authors' institution in the mid-1980s. The new management principles affected referral guidelines, diagnostic and monitoring methods, and pharmacological and surgical treatment in a neurointensive care setting. The impact of such changes on the outcome of aneurysmal SAH over a longer period of time has not previously been studied in detail. This was the present undertaking.Methods. The authors analyzed all patients with SAH admitted to the neurosurgery department between 1981 and 1992. This period was divided in two parts, Period A (1981–1986) and Period B (1987–1992), and different aspects of management and outcome were recorded for each period. In total, 1206 patients with SAH (mean age 52 years, 59% females) were admitted; an aneurysm presumably causing the SAH was found in 874 (72%).The 30-day mortality rate decreased from 29% during the first 2 years (1981–1982) to 9% during the last 2 years (1991–1992) (Period A 22%; Period B 10%; p < 0.0001) and the 6-month mortality rate decreased from 34 to 15% (Period A 26%; Period B 16%; p < 0.001). At follow-up review conducted 2 to 9 years (mean 5.2 years) after SAH occurred, patients were evaluated according to the Glasgow Outcome Scale. Subarachnoid hemorrhage—related poor outcome (vegetative or dead) was reduced (Period A 30%; Period B 18%; p < 0.001). There was an increase both in patients with favorable outcome (good recovery and moderate disability) (Period A 61%; Period B 66%) and in those with severe disability (Period A 9%; Period B 16%; p < 0.01).Conclusions. This study provides evidence that the prognosis for patients with aneurysmal SAH has improved during the last decades. The most striking results were a gradual reduction in mortality rates and improved clinical outcomes in patients with Hunt and Hess Grade I or II SAH and in those with intraventricular hemorrhage. The changes in mortality rates and the clinical outcomes of patients with Hunt and Hess Grades III to V SAH were less conspicuous, although reduced incidences of mortality were seen in some subgroups; however, few survivors subsequently appeared to attain a favorable outcome.