This randomized controlled trial aims to compare the effects of ultrasound-guided lateral Quadratus Lumborum Block (QLB) and Transversalis Fascia Plane (TFP) block on postoperative analgesia in patients undergoing laparoscopic inguinal hernia repair. Ninety patients will be randomly assigned to one of three groups: Group QLB, Group TFP, or Group Control. The primary objective is to compare postoperative pain scores (NRS) at various time points within the first 24 hours. Secondary objectives include evaluating the need for rescue analgesia, total tramadol consumption, and the incidence of opioid-related side effects.

Laparoscopic inguinal hernia repair is a standard, minimally invasive procedure. However, moderate pain is common in the first 24 hours postoperatively, originating from somatic pain at trocar sites and visceral pain from peritoneal irritation and mesh placement. Multimodal analgesia, including fascial plane blocks, is recommended to reduce opioid consumption and improve pain control.

In this prospective, randomized, controlled, single-center trial, 90 patients (ASA I-III, aged 18-65) scheduled for elective laparoscopic inguinal hernia repair under general anesthesia will be allocated into three parallel arms (n=30 each) via computer-based randomization.

Group QLB: Will receive bilateral ultrasound-guided lateral Quadratus Lumborum Block (total 40 mL 0.25% bupivacaine) prior to extubation, along with 10 mL 0.25% bupivacaine infiltration at port sites.

Group TFP: Will receive bilateral ultrasound-guided Transversalis Fascia Plane Block (total 40 mL 0.25% bupivacaine) prior to extubation, along with 10 mL 0.25% bupivacaine infiltration at port sites.

Group Control: Will receive only port site infiltration (total 20 mL 0.25% bupivacaine).

All procedures will be performed aseptically by the same surgical and anesthesia team. Postoperatively, all patients will receive 1 g intravenous paracetamol every 8 hours. Postoperative pain will be assessed using the Numeric Rating Scale (NRS) by an anesthesiologist blinded to the group allocation. Intravenous tramadol (100 mg) will be administered as rescue analgesia if the NRS score is ≥ 4. Total 24-hour tramadol consumption, along with block-related complications and opioid-related side effects (nausea, vomiting, sedation), will be recorded.

Inclusion Criteria:

• Scheduled for elective laparoscopic inguinal hernia repair.
• American Society of Anesthesiologists (ASA) physical status I, II, or III.
• Age between 18 and 65 years.
• Provided written informed consent.

Exclusion Criteria:

• History of allergy to local anesthetics.
• Presence of coagulopathy.
• Signs of infection at the intended block application site.
• Body Mass Index (BMI) ≥ 35 kg/m².
• History of chronic opioid use.
• Presence of neurological disease.
• Refusal to participate in the study.