Effectiveness of local warming in facilitating peripheral intravenous cannulation: A systematic review and meta-analysis

Background: Peripheral venous cannulation is a critical yet sometimes difficult procedure, especially in pediatric or vasoconstricted patients. Local warming has been proposed to enhance venous dilation and improve cannulation success. Objective: To evaluate the effect of local warming on peripheral venous cannulation success rates and vascular cross-sectional area (CSA). Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Databases searched included PubMed, Scopus, Embase, and Cochrane Library up to June 2025. Randomized controlled trials (RCTs) assessing the impact of local warming versus control on venous cannulation outcomes were included. Risk ratios (RRs) and standardized mean differences (SMDs) with 95% confidence intervals (CI) were pooled using a random-effects model. Risk of bias and GRADE certainty were assessed. PROSPERO registration: CRD420251067877. Results: Five RCTs involving both pediatric and adult populations were included. Local warming significantly improved cannulation success (RR: 1.30, 95% CI: 1.17–1.45; I ² = 0%). It also increased vascular CSA (SMD: 0.91, 95% CI: 0.65–1.17; I ² = 0%). Subgroup analysis revealed consistent benefits in pediatric patients. Sensitivity analyses confirmed robustness of findings. Funnel plot showed no major publication bias. Conclusions: Local warming is an effective, non-invasive intervention to improve peripheral venous access, particularly in pediatric patients. It significantly enhances both cannulation success and vascular CSA with high consistency across studies.