Objectives: This randomised controlled trial aims to evaluate the impact of low-dose intravenous nalmefene on anaesthesia recovery in adult patients aged 18-65 undergoing surgery under general anaesthesia.
Design: This was a multicentre, randomised, double-blind trial with two parallel arms clinical study.
Setting: Four hospitals from China PARTICIPANTS: A total of 514 patients aged 18-65 who underwent elective orthopaedic, urologic and thoracic surgeries.
Interventions: On completion of skin suturing, the intervention group received a single intravenous dose of nalmefene (0.25 µg/kg). The control group received an equivalent volume of normal saline at the same time point.
Primary and secondary outcome measures: The primary outcome was the interval time between the end of anaesthesia and the Aldrete score ≥9 being achieved in the postanaesthesia care unit (PACU). The secondary endpoints included the time interval from the end of operation to extubation; Richmond Agitation Sedation Scale (RASS) score at extubation; the time at Montreal Cognitive Assessment Scale (MoCA) orientation score ≥5; visual analogue scale (VAS) score in PACU and 24 hours postoperatively.
Results: 514 patients were included in the Intention-to-Treat (ITT) analysis. The time interval between the end of anaesthesia and Aldrete score reached ≥9 in PACU was significantly shorter in the intervention group than in the control group (mean (SD) 24.8 (11.8) min vs 33.8 (12.5) min; 95% CI -8.8 (-10.8 to -6.7); p<0.001). Furthermore, the time interval from the end of surgery to extubation was shorter in the intervention than in the control group (mean (SD) 20.0 (9.9)min vs 27.6 (11.6) min; 95% CI -7.6 (-9.43 to -5.7), p<0.001). The time at Montreal cognitive assessment score ≥5 was also shorter in the control than in the intervention group (mean (SD) 20.0 (15.9) min vs 27.0 (20.5) min; 95% CI -7.0 (-10.2 to -3.8); p<0.001). Compared with the control group, the intervention group had better analgesic effect at the recovery endpoint (P Aldrete score ≥A was achieved as well as lower 24 hours points postoperatively (p<0.05)).
Conclusions: In patients aged 18-65 who underwent elective orthopaedic, urologic and thoracic surgeries, low-dose nalmefene administered at the end of surgery can accelerate postanaesthesia recovery without compromising analgesic effects.
Trial registration number: NCT04713358.
Keywords: Adult anaesthesia; Anaesthesia in urology; Health.
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