Treatment Strategies for Delayed Cerebral Ischaemia After Subarachnoid Haemorrhage: A Systematic Review

Abstract

ABSTRACT Delayed cerebral ischaemia (DCI) is a devastating complication which may occur after aneurysmal subarachnoid haemorrhage (SAH). It significantly increases mortality among SAH patients and leads to poor functional outcomes. Due to uncertainty among researchers and healthcare professionals regarding the pathophysiology and clinical diagnosis of DCI, no sufficient treatment model has been proposed. Aims and Objectives: The aim of this study is to address the literature gap in the current recommendations on the treatment for DCI. In doing so, we aim to bring to light potential avenues for novel therapies, which have not yet been addressed by treatment models, and to inform directions for future research. Methodology: Three electronic databases (Pubmed, Medline, and Embase) were systematically searched for randomised control trials (RCT) and retrospective cohort studies that addressed various treatment methods of DCI. These included data on the use of statins, endovascular rescue therapy (ERT), calcium antagonists and vasodilators, assessing their efficacy and safety profile. Studies were included on the basis of predetermined inclusion criteria. Primary and secondary outcomes included mortality rate, ICU and hospital length of stay, incidence of vasospasm, and adverse events for each treatment modality. Results: A total of nine studies were included: 3 RCT and 6 retrospective cohort studies. No study reported a significant increase in adverse events, indicating that the included treatments are safe to use. A significant improvement in the severity of vasospasm was reported after the given treatment modalities; however, changes in functional outcome (Glasgow Coma Scale, Glasgow Outcome Scale, modified Rankin Scale) were not significant. Only the studies on statins included the length of hospital stay as a measure, which also showed insignificant results. Adjunct therapy of ERT with nimodipine appears to improve functional outcomes compared to single therapies. Conclusion: There is currently insufficient evidence for the addition of milrinone and statins to the current guidelines. However, adjuvant therapies show promise and more combinations should therefore be explored in the future. Keywords: Delayed cerebral ischaemia, cerebral vasospasm, aneurysmal subarachnoid haemorrhage, treatment, statins, endovascular rescue therapy, balloon angioplasty, nimodipine, milrinone