Analgesia using intrathecal morphine to improve quality of recovery after minimally invasive major abdominal surgery (AIM Trial): study protocol for a multicentre randomised controlled trial.

BACKGROUND

Evidence to support the effectiveness of intrathecal morphine in patients undergoing minimally invasive abdominal surgery is largely based on small, single-centre studies. We therefore designed a large, multi-centre clinical trial to investigate the effect of intrathecal morphine with local anaesthetic on patient postoperative quality of recovery. The primary objective is to compare quality of recovery on postoperative Day 1. The secondary objectives are to compare opioid consumption, pain scores, and opioid-related adverse events.

METHODS

This multi-centre, prospective, randomised controlled trial will recruit 280 adult patients undergoing minimally invasive major abdominal surgery. The intervention group will receive 200 mcg of intrathecal morphine with local anaesthetic, as part of a multimodal analgesic strategy. Following safety analysis after the first 100 patients the dose of ITM will increase to 300 mcg. The control group will receive non-neuraxial multimodal analgesia.

CONCLUSIONS

This trial is expected to provide evidence on the effectiveness and the safety of two different ITM doses with local anaesthetic in major minimally invasive abdominal surgery.

CLINICAL TRIAL REGISTRATION

ACTRN12623001347651 (ANZCTR Registry Number).

PROTOCOL VERSION NUMBER AND DATE

1.0, May 2, 2024.