Intraoperative fentanyl versus paracetamol for ultrasound-guided oocyte retrieval analgesia: a randomised clinical trial

Abstract

Background

Despite its brief duration, transvaginal ultrasound-guided oocyte retrieval is a potentially painful procedure often managed with opioid-based sedation. This study evaluated whether intravenous paracetamol could provide postoperative analgesia comparable to fentanyl.

Methods

We investigated two multimodal anaesthesia regimens, one including intravenous (IV) paracetamol and the other IV fentanyl, for postoperative analgesia in a single-center, single-blinded, randomised, non-inferiority trial. Healthy women with ≤15 follicles identified by ultrasound undergoing oocyte retrieval under general anaesthesia (propofol) were randomised to receive IV paracetamol 1000 mg vs IV fentanyl 100 μg. The primary outcome was median postoperative pain on an 11-point numerical rating scale (NRS) scores (0 = no pain, 10 = worst imaginable pain) at five predefined time points within the first two postoperative hours. Secondary outcome measures included sedation scale (Pasero), Aldrete scale, discharge time, patient satisfaction with anaesthesia (5-point Likert scale), administration of supplemental analgesia and antiemetics.

Results

In total, 100 patients were enrolled with 95 cases analysed. Median [IQR] NRS scores were 0 [0–1] in the paracetamol group and 0 [0–1] in the fentanyl group (P =0.31), indicating non-inferiority. There were no differences between groups in the rate of low Pasero score (84% with paracetamol vs 87% with fentanyl, P =0.98), Aldrete scores, use of postoperative analgesia, prolonged discharge time (>60 minutes) or satisfaction scores (median 5 in both groups, P =0.90).

Conclusion

Intra-operative IV paracetamol 1000 mg was non-inferior to fentanyl 100 μg for post-procedure analgesia, suggesting opioid-free anaesthesia may be an acceptable approach for ≤15 follicles ultrasound-guided oocyte retrievals.