12. Needle-less Local Anesthetic Device for Subcutaneous Etonogestrel Insertion

Abstract

Background

The subcutaneous etonogestrel implant is a first-line option for long-acting reversible contraceptive in adolescents but is often avoided due to fear of procedural pain. This early randomized control trial aimed to evaluate how a novel, needle-less device (J-Tip TM) for local anesthesia affected pain perception and overall patient satisfaction during implant insertion.

Methods

This IRB approved study recruited adolescents 13-21 years of age interested in the etonogestrel implant. Participants were randomized to receive intradermal lidocaine via the needle-less device or the traditional needle-based approach (control group). They were asked to complete a modified Amsterdam Preoperative Anxiety and Information Scale before and after the procedure and to report their pain scores via a 10-point Visual Analogue Scale throughout the procedure. Demographic and basic medical information were collected. Statistical analysis included student t-tests, correlation analysis, and effect size analysis with Cohen's d.

Results

Twenty-three participants were consented (11 controls and 12 interventions). Both groups had similar demographics and pre-procedure anxiety levels. Most were 16 years of age and denied having pre-existing mood disorders. Pain scores during lidocaine injection were significantly higher in the control group compared to the intervention group (mean = 5.8 ± 2.0 vs 0.8 ± 1.3, p< 0.001, range = 3-9 vs 0-3, d = 2.95). Pain scores during Nexplanon insertion were significantly lower in the control group compared to the intervention group (mean= 0.8 ± 0.9 vs 4.1 ± 2.5, p < 0.001, range = 0-2 vs range = 1-8, d = -1.81). In the post-procedure survey, recalled pain during insertion and overall satisfaction with the procedure among patients, parents and providers were not significantly different. Pre-procedure anxiety and expecting the procedure to be uncomfortable were positively correlated with increased stress during the procedure (r = 0.6, r=0.45) but not significantly correlated with any pain scores during the procedure.

Conclusions

While the new device may effectively reduce pain during administration of local anesthesia, its efficacy compared to traditional needle-based injection methods prior to implant insertion warrants further investigation. Our findings also emphasize the importance of managing patient expectations regarding comfort and pain, which may enhance overall satisfaction and reduce perceived pain and stress during the procedure. This study serves as a pilot to inform a larger randomized controlled trial aimed at improving the patient experience during etonogestrel implant insertions.