The effect of ultrasound-guided rectus sheath block on postoperative analgesia in robot assisted prostatectomy: A randomized controlled trial.

Background: Postoperative pain continues to represent an important problem even after minimally invasive robotic-assisted laparoscopic radical prostatectomy, which results in discomfort in the postoperative period and sometimes prolongs hospital stays. Regional anesthesia and analgesia techniques are used in addition to systemic analgesics with the multimodal approach in postoperative pain management. Ultrasound-guided fascial plane blocks are becoming increasingly important, especially in minimally invasive surgeries. Another important cause of discomfort is urinary catheter pain. The present randomized controlled study investigated the effect of rectus sheath block on postoperative pain and catheter-related bladder discomfort in robotic prostatectomy operations.

Methods: This randomized controlled trial was conducted from March to August 2022. Written informed consent was obtained from all participants. Approval for the study was granted by the Clinical Research Ethics Committee. All individuals provided written informed consent, and adults with American Society of Anesthesiologists Physical Condition classification I to III planned for robotic prostatectomy operations under general anesthesia were enrolled. Following computer-assisted randomization, patients were divided into 2 groups, and general anesthesia was induced in all cases. Rectus sheath block was performed under general anesthesia and at the end of the surgery. No fascial plane block was applied to the patients in the non-rectus sheath block (RSB) group.Postoperative pain and urinary catheter pain were assessed using a numerical rating scale. Fentanyl was planned as rescue analgesia in the recovery room. In case of numerical rating scale scores of 4 or more, patients were given 50 µg fentanyl IV, repeated if necessary. The total fentanyl dose administered was recorded in the recovery room. IV morphine patient-controlled analgesia was planned for all patients. All patients' pain (postoperative pain at surgical site and urethral catheter discomfort) scores and total morphine consumption in the recovery unit and during follow-ups on the ward (3, 6, 12, and 24 hours) in the postoperative period were recorded.

Results: Sixty-one patients were evaluated. Total tramadol consumption during follow-up on the ward was significantly higher in the non-RSB group. Fentanyl consumption in the postanesthesia care unit was significantly higher in the non-RSB group. Total morphine consumption was significantly lower in the RSB group at 0 to 12 hours and 12 to 24 hours. Total opioid consumption was 8.81 mg in the RSB group and 19.87 mg in the non-RSB group. A statistically significant decrease in urethral catheter pain was noted in the RSB group at all time points.

Conclusion: RSB exhibits effective analgesia by significantly reducing postoperative opioid consumption in robotic prostatectomy operations.