BACKGROUND: Ultrasound-facilitated delivery of topical anesthetics has been used to achieve effective anesthesia within 5 minutes for venipuncture and the insertion of intravenous access devices, but has never been studied for blood donation.
STUDY DESIGN AND METHODS: This study was a single-center, prospective, randomized, sham treatment–controlled, single-blinded clinical evaluation. Repeat donors were randomly assigned to undergo treatment with ultrasound and topical anesthetic or sham ultrasound and placebo anesthetic before phlebotomy for whole blood donation. The primary outcome measures were pain assessments using the Verbal Categorical Scale (VCS) and the Visual Analogue Scale and the assessment of skin irritation at the target site.
RESULTS: One-hundred subjects were enrolled and all completed the study. Compared to the sham/placebo control group, donors receiving ultrasound/anesthetic had lower pain scores on the VCS (1.81 ± 0.67 vs. 2.17 ± 0.68; p = 0.01) and Visual Analog Scale (17.2 ± 15.5 vs. 27.6 ± 19.5; p = 0.006). The proportion of subjects in the treatment group who experienced skin irritation (8%) was similar to that in the control group (2%; p = 0.20).
CONCLUSION: Ultrasound-enhanced delivery of topical anesthetic was demonstrated to be a safe means of quickly achieving clinically meaningful reduction in the pain of phlebotomy for whole blood donation compared to sham/placebo treatment.