Abstract

Background Chronic subdural haematoma (cSDH) is a common neurosurgical condition, many patients have significant comorbidity or are living with frailty. Surgery is effective and can be performed under local anaesthesia (with or without sedation) or general anaesthesia. Optimal technique for both GA and LA is poorly defined but similar questions have been explored in other surgical settings. We sought to clarify the breadth of evidence for anaesthetic technique in cSDH surgery, while drawing on relevant literature from other disciplines to understand how a definitive trial of this question could be performed.

Materials and Methods We used a combination of systematic and narrative literature search, review of trial registries, the Cochrane database, and a survey of anaesthetic and neurosurgical practitioners. An updated systematic review and meta-analysis of trial and observational studies in this area was performed following PROSPERO registration.

Results We identified a paucity of high-quality studies, especially randomised trials, exploring this question. The literature, and a survey of anaesthetists and surgeons, suggest that local anaesthesia may bring benefits in shorter hospital stay and reduced complications. Registered studies in this field are single centre in nature while a synthesis of Cochrane reviews in other fields echoes issues of equipoise, study design, and outcome choice as key challenges in designing a definitive trial.

Conclusions There is significant interest in this topic as evidenced by published and emerging literature and views of anaesthetists and surgeons. No registered trial is multi-centre or draws on challenges identified in similar trials from other disciplines. Our paper helps create a roadmap to a definitive trial of this crucial question.

Competing Interest Statement

The ICENI initiative and its working groups was funded by the Addenbrookes Charitable Trust (900268) and the Association of Anaesthetists/Anaesthesia (via the National Institute for Academic Anaesthesia - WKR0-2021-0014). DJS is funded by the National Institute for Health and Care Research (NIHR304395). The views expressed are those of the authors and do not reflect the position of the NIHR or department of health and social care. This work is supported by the NIHR Cambridge Biomedical Research Centre. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. PJH is supported by the NIHR (Senior Investigator Award, NIHR Global Health Research Group on Acquired Brain and Spine Injury, NIHR Health Tech Research Centre for Brain Injury, Cambridge Biomedical Research Centre).

Funding Statement

The ICENI initiative and its working groups was funded by the Addenbrookes Charitable Trust (900268) and the Association of Anaesthetists/Anaesthesia (via the National Institute for Academic Anaesthesia - WKR0-2021-0014). DJS is funded by the National Institute for Health and Care Research (NIHR304395). The views expressed are those of the authors and do not reflect the position of the NIHR or department of health and social care. This work is supported by the NIHR Cambridge Biomedical Research Centre. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. PJH is supported by the NIHR (Senior Investigator Award, NIHR Global Health Research Group on Acquired Brain and Spine Injury, NIHR Health Tech Research Centre for Brain Injury, Cambridge Biomedical Research Centre).

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Approval for the project was under the development of the ICENI CSDH guideline-https://www.tandfonline.com/doi/full/10.1080/02688697.2024.2413445#d1e1529

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data Availability

All data produced in the present work are contained in the manuscript

Abbreviations and AcronymsCSDHchronic subdural haematomaLASlocal anaesthetic with or without sedationGAgeneral anaestheticRCTrandomised-controlled trialNRTnon-randomised trialNOSNewcastle Ottawa ScaleICENIImproving Care in Elderly Neurosurgery Initiative