Recovery of Cognitive Function After Surgery for Aneurysmal Subarachnoid Hemorrhage

Abstract

Background and Purpose-Abnormalities in neurocognitive function are common after surgery for aneurysmal subarachnoid hemorrhage, even among patients with good functional outcomes. The time course of neurocognitive recovery, along with the long-term effects of mild intraoperative hypothermia (33°C) and aneurysm location, is unknown. We determined these in a subset of subarachnoid hemorrhage patients enrolled in the Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST). Methods-We performed a longitudinal, multicenter, prospective, blinded study of adult IHAST patients with a Glasgow Outcome Scoreϭ1 or 2 (independent function), 3 months postsurgery and a matched control group (nϭ45). Subjects were tested with a 5-test cognitive function battery and standard neurological evaluations at 3, 9 and 15 months postsurgery. The primary outcome measure was a composite score on cognitive test performance. Results-There were 303 IHAST patients available for inclusion: 218 eligible, 185 enrolled (89 hypothermic, 96 normothermic). Significant cognitive improvement was noted from 3 to 9 (PϽ0.001) and 3 to 15 (PϽ0.001) months in both hypothermic and normothermic groups, even after adjusting for practice effects observed in the control group. No significant change was identified between 9 and 15 months. Neither mild hypothermia nor aneurysm location (anterior communicating artery versus others) had a significant effect on recovery over time or frequency of cognitive impairment. Compared with control group, the frequency of cognitive impairment (Z score ϽϪ1.96) in all patients at 3, 9 and 15 months was 36%, 26% and 23%, respectively. Conclusions-In this population, cognitive improvement continued beyond 3 months, with a plateau between 9 and 15 months. This was not affected by the use of intraoperative hypothermia or anatomical location of aneurysm. (Stroke.

Long-Term Cognitive Deficits After Subarachnoid Hemorrhage in Rats

“…Human SAH results in a wide range of sustained cognitive dysfunction [1,2,25]. Visual and spatial memory is commonly affected.…”

Intravenous Magnesium Sulphate for Aneurysmal Subarachnoid Hemorrhage (IMASH)

“…26 Abnormalities in cognitive function are common after surgery for aneurysmal SAH, even among patients with a good functional outcome, and can occur in up to 44% of survivors. [27][28][29] This academically funded study was done without any industry support using generic medications and weakness would include lack of on-site trial monitoring due to restraints in funding. We have not incorporated daily blood pressure data in the trial design.…”

Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage

“…Multiple studies using diverse designs have consistently demonstrated that intellectual impairment is very prevalent after aSAH. Although cognitive function tends to improve over the first year, 64 global cognitive impairment is still present in Ϸ20% of aSAH patients and is associated with poorer functional recovery and lower quality of life. 65 Cognitive deficits and functional decline are often compounded by mood disorders (anxiety, depression), fatigue, and sleep disturbances.…”