A randomized controlled trial comparing Ametop™ with placebo for reducing pain associated with local anesthetic skin infiltration before neuraxial anesthesia in parturients.
BACKGROUND
Between 10-22% of the general population experience needle phobia. Needle phobic parturients are at increased risk of adverse outcomes. We assessed the efficacy of topical Ametop™ (tetracaine 4%) gel in reducing the pain associated with local anesthetic skin infiltration before neuraxial block in non-laboring women.


METHODS
This was a prospective, randomized, double-blind, placebo-controlled study. Ametop™ or placebo was applied to the skin of the lower back at least 20min before neuraxial block using a standardized technique with 1% lidocaine skin infiltration. The primary outcome was numeric pain score (0-10) 30s after lidocaine infiltration. Groups were compared using Welch's t-test.


RESULTS
Thirty-six subjects in each group were analyzed. There was a statistically significant difference in the mean (standard deviation) pain score between the Ametop™ and the placebo groups: 2.36±1.80 and 3.51±2.22, respectively (P=0.019). There were no significant adverse events.


CONCLUSIONS
The mean numeric pain score in the Ametop™ group was 33% lower compared to the placebo group. Topical Ametop™ gel applied at least 20min before local anesthetic infiltration of the skin prior to neuraxial block in elective cesarean delivery may be a useful adjunct in needle phobic women.
Department of Anesthesia, BC Women's Hospital, Vancouver, BC, Canada. Electronic address: trevorkavanaghster@gmail.com.
T
T
Kavanagh
Department of Anesthesia, BC Women's Hospital, Vancouver, BC, Canada.
A
A
Dube
Biostatistician, Women's Health Research Institute, Vancouver, BC, Canada.
A
A
Albert
Department of Anesthesia, BC Women's Hospital, Vancouver, BC, Canada.
V
V
Gunka
D000328:Adult; D000767:Anesthesia, Epidural; D000773:Anesthesia, Obstetrical; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D010146:Pain / Q000517:prevention & control*; D036801:Parturition; D011247:Pregnancy; D011446:Prospective Studies; D013748:Tetracaine / Q000008:administration & dosage* / Q000009:adverse effects
D000779:Anesthetics, Local; D013748:Tetracaine
Ametop™; Lidocaine; Neuraxial block