Improved survival after aneurysmal subarachnoid hemorrhage: review of case 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.