Chronic Subdural Haematoma: Systematic Review Highlighting Risk Factors for Recurrent Bleeds

Abstract

Introduction: Chronic subdural haematoma (CSDH) is one of the commonest forms of intracranial haemorrhage. Surgical drainage of CSDH is a routine operation in the modern neurosurgical practice which has shown to be the most effective way in treating this entity; however, the incidence of recurrence of the haematoma post operatively remains as high as 26.5%. The risk factors for CSDH recurrence remains an area of ongoing research.
Objective: We have conducted a systematic review to evaluate the available literature addressing the risk factors for CSDH recurrence, aiming to minimise or at least identify patients at higher risk of recurrence in order to decrease associated morbidity.
Methods: Ovid via Medline, PubMed, and Google scholar databases were searched for eligible studies, search results were then limited to studies in English language, Humans and studies published within the last 5 years. The included studies were critically appraised using the Critical Appraisal Skills Programme (CASP) tool, and each study has then been ranked using the Harbour and Miller hierarchy of ranking.
Results: Based on available evidence, we classified the risk factors associated with recurrence to patients’, radiological, and surgical factors. Patient factors include history of seizures, trauma, alcoholism, brain atrophy, and presence of CSF shunts, while the role of diabetes in relation to the recurrence is controversial. Radiologically the presence of air in the subdural space post-operatively, the width of the haematoma, and the presence of bilateral CSDHs are associated with increased risk of recurrence. While the predictive value of multiple membranes in the CSDH remains controversial. Surgically, the risk of recurrence was noted to be higher in patients with parietal or occipital compared to those who had frontal burr hole drainage, also placing a subdural drain decreases the chance of recurrence and some evidence showed better outcomes for frontally placed drains. The role of anti-inflammatory agents (including steroids) remains an area of ongoing debate.
Conclusions: Risk factors for CSDH can be divided into patients’, radiological, and surgical factors. We encourage health care providers to minimize if not prevent potentially avoidable factors. Patients with increased risks for recurrence should be identified early by the treating team and when possible should be informed about their higher than usual risk of recurrence. Moreover this review highlights the general lack of a sufficiently.