Ketamine holds up against fentanyl for procedural sedation in outpatient surgical abortion

Intravenous (IV) treatment with ketamine is as good as that with fentanyl for procedural sedation in patients undergoing first-trimester outpatient surgical abortion, as reflected in patients’ satisfaction with their anaesthesia, according to a study.

The study randomized 110 patients to receive either IV ketamine (n=57) or IV fentanyl (n=53) for first-trimester surgical abortion up to 13 6/7 weeks of gestation. Ketamine 200–500 μg/kg IV was administered over 2 minutes and repeated every 5 minutes until appropriate analgesia was achieved. On the other hand, fentanyl 0.5–1 μg/kg IV was given over 2 minutes and repeated every 5 minutes until appropriate analgesia was achieved. All patients received midazolam 2 mg intravenously.

The primary outcome of patient satisfaction with anaesthesia, measured using the Iowa Satisfaction with Anesthesia Scale immediately after the procedure, was noninferior in the ketamine group relative to the fentanyl group (mean score 2.4 vs 2.2), with a risk difference of 0.20 (95 percent confidence interval [CI], 0.11–0.52).

However, patients who received ketamine reported more hallucinations than those who received fentanyl.

Secondary outcomes such as postoperative pain, additional pain medication necessary during the procedure and on discharge, physician satisfaction, and time to discharge did not significantly differ between the ketamine and fentanyl groups.