Use of Remifentanil Associated with Lidocaine for Feticides in Late Terminations of Pregnancy: A Randomized Clinical Trial

Abstract

Introduction: In France, performance of a termination of pregnancy is legally possible without any gestational age limit. After 22 weeks of gestation, a feticide is ethically performed using usually sufentanil and lidocaine. The aim of this study was to compare the use of remifentanil, a fast-acting morphine-derivating product, instead of sufentanil. Methods: This 2-center randomized, controlled, single-blinded phase-III treatment trial had 2 parallel arms: an experimental group using remifentanil with lidocaine versus a control group receiving sufentanil associated with lidocaine. This trial took place over a 40-month period. The primary outcome was time to fetal asystole after lidocaine injection. The secondary outcome measures were the procedure’s success rate, the rate of serious maternal side effects, and the presence of cellular or tissue modifications. Results: The study included 66 women, randomized into 2 groups of similar size and characteristics. Time to fetal asystole did not differ significantly between the groups, with a delay of 4 min (Q1−Q3, 2–11) in the sufentanil group and 4 min (Q1−Q3, 1–10) in the remifentanil group (p = 0.84). Similarly, the success rate of the procedure did not differ significantly. Fetal asystole was procured in <2 min and persisted >1 min for 16 (25.8%) women in our total population: 7 (22.5%) in the sufentanil group and 9 (29.0%) in the remifentanil group, p = 0.77. No severe maternal side effects were observed. Among the 49 fetopathological examinations performed, the few tissue and cell modifications observed did not cause any interpretation difficulties in either group. Discussion/Conclusion: Use of remifentanil instead of sufentanil for feticide procedure did not improve time to fetal asystole. No harmful effect was observed for either maternal tolerance or interpretation of the histologic slides.