Immediate Effects of a Single Session Bloodletting for Acute Stroke Patients with Impaired Consciousness: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objectives: Bloodletting has long been a widely used emergency measure for acute stroke and sudden loss of consciousness in East Asia, and the belief in the usefulness of bloodletting still exists in these cultures. This study aimed to evaluate the immediate effects of a single session of bloodletting for acute stroke patients with impaired consciousness.Methods: Eight databases and four trial registries were searched to identify randomized controlled trials (RCTs) published until June 2024. Meta-analyses and quality assessments were performed using the Cochrane Method for Systematic Reviews, with evidence certainty evaluated via the GRADE framework. The mean difference (MD) with a 95% confidence interval (CI) was calculated.Results: Three RCTs met our eligibility criteria, of which two RCTs that stratified participants into three subgroups according to stroke lesion volume were included in the meta-analysis. The MDs (95% confidence interval) in the change of Glasgow coma scale (GCS) score in the small, medium, and large lesion group were 0.44 (0.42 to 0.46), 0.10 (0.08 to 0.12), and -0.02 (-0.04 to 0.00); and 0.68 (0.65 to 0.71), 0.21 (0.19 to 0.23), and 0.09 (0.07 to 0.11) at 30 and 45-50 minutes after the intervention, respectively. The risk of bias in the included studies was high and the certainty of the evidence was very low.Conclusions: We reached the following tentative conclusions based on limited evidence. A single session of bloodletting may immediately improve the GCS scores for acute stroke patients with impaired consciousness. This effect tends to be greater in patients with smaller lesion volumes and is enhanced within a limited timeframe.