The Effect of Ultrasound-Guided Bilateral Rectus Sheath Block Versus Wound Infiltration on Postoperative Pain in Gynecooncological Patients Undergoing Laparotomy With Midline Incision: Randomized Controlled Triple Blinding Study

This single-center prospective,observational study was approved by Institutional Ethics Committee (Decision number: 2023/514/257/31, Date: 29/05/2023) and was performed in accordance with the Declaration of Helsinki.. Between June and September 2023, ultrasound guided bilateral rectus sheath block or local anesthesia administered to the patients in the gynecological oncology operating room of the University of Health Sciences Kartal Dr Lutfi Kırdar City Hospital at the end of the surgery. In the postoperative period, the pain level of the patients was recorded with the numerical rating scale at 2, 6, 12 and 24 hours by an anesthesiologist who was unaware of the application. The data were entered into the table by an anesthesiologist who did not know which application was performed. Thus, data were recorded using a randomized triple blinding method in which the patient, the researcher, and the recording staff were blinded.

All patients underwent preoperative evaluation one day before surgery and written informed consent was obtained for participation for the study. The procedure to be performed on the patients was planned in accordance with the randomization made by the statistician. The anesthesiologist who would perform the intervention participated in the study blindly to the drugs and groups. Patients in Group I underwent postoperative ultrasound-guided bilateral rectus sheath block at the T9-10 level with 20 ml of 0.25% bupivacaine (40 ml in total). For the patients in Group II (control group), 20 ml of 0.25% bupivacaine was applied subcutaneously to each wound lip (40 ml in total). At the end of the surgery, 100 mg tramadol iv and paracetamol 1mg/kg iv were administered to both groups as analgesics.

Pain, ranging from 0 (no pain) to 10 (worst imaginable), was queried by another anesthesiologist who was blind to the procedure. 2*1 non-steroidal anti-inflammatory was routinely administered as an analgesic in the ward, but the first application time was planned by questioning the patient's pain. Rescue analgesia with tramadol was administered if the patient ranged the pain >4 . Pain was measured at the 2nd, 6th, 12th and 24th hours postoperatively, and tramadol consumption was recorded.