Effects of 4% Lidocaine and EMLA in children undergoing venous procedures on vein caliber, pain, and child collaboration: Retrospective observational study

Background: Topical anesthetics such as 4% Lidocaine and Eutectic Mixture of Local Anesthetics (EMLA) are used for venipuncture and intravenous (IV) cannulation. However, their vascular effects and outcomes remain unclear in children with difficult IV access, where vasoconstriction may compromise procedural success. Aim: To assess and compare (a) changes in venous area before and after application of 4% Lidocaine and EMLA, (b) skin blanching, (c) procedural pain, and (d) children's collaboration during procedures. Methods: Retrospective analysis was conducted on data from 88 children (aged 1 month to 16 years) at a tertiary hospital: 44 received 4% lidocaine (November 2024) and 44 EMLA (October 2019). Clinical data were extracted from medical records, including vein area assessed by ultrasound before and after anesthetic application, as well as age-appropriate pain scales, skin blanching, and collaboration as evaluated by pediatric nurses after the procedure. Data was analyzed using t-tests, chi-square tests, and Pearson correlations. Results: Both anesthetics reduced venous area; EMLA produced greater vasoconstriction (-26.28% vs -3.27%, p = .002) and skin blanching (72.73% vs 25%, p < .001) than 4% Lidocaine. Pain was low in both groups (p = .07). Children who received EMLA showed higher collaboration (97.73% vs 75%, p < .001). Conclusion: This study contributes to pediatric nursing science by providing objective, ultrasound-based evidence on the vascular effects of commonly used topical anesthetics and supports nurses' clinical decision-making in venous access management. Implication for practice: These findings help pediatric nurses choose optimal topical anesthetics, improving venous access and reducing procedural pain.