Postoperative Analgesic Efficacy of Adjuvant Quadratus Lumborum Block in Open Inguinal Hernia Surgery

primary aim : Compare the time to first rescue analgesia in patients following the application of non-adjuvant Quadratus Lumborum Block and adjuvant Quadratus Lumborum Block for postoperative analgesia after inguinal hernia surgeries performed under spinal anesthesia.

secondary aims are to: to compare and evaluate the total analgesic consumption over 24 hours Compare NRS (Numerical Rating Scale) values (at rest and dynamic) in patients during postoperative follow-ups at 4, 8, 12, and 24 hours.

Compare side effects such as postoperative nausea and vomiting. In trunk blocks, local anesthesia is applied to the interfascial area between the abdominal wall or back muscles. Local anesthetics and steroids are used for this purpose. The analgesic efficacy of steroids is known from their perineural applications. Due to the lack of blood circulation and vascularization in the interfascial area, the absorption of local anesthetics is slow, providing prolonged analgesic effects. Trunk blocks applied in these regions are used as part of multimodal analgesia. The effectiveness of trunk blocks may vary based on the patient's anatomical differences and previous surgeries, but analgesic efficacy is generally observed for an average of 8-12 hours. the investigators believe that with the use of adjuvants, these durations will be extended, and analgesic efficacy will increase.

In this study, it is planned to add a total of 8 mg of dexamethasone to the local anesthetic agent for patients undergoing adjuvant anterior Quadratus Lumborum Block. In studies conducted in the field of trunk blocks, the expected duration of analgesia is an average of 8-12 hours. In this study, the block application is planned to be preoperative. Dexamethasone was chosen as an adjuvant to extend the expected analgesia duration of 8-12 hours and to increase analgesic efficacy. Dexamethasone is known to be effective and safe when used as an adjuvant in all nerve blocks.

To reduce opioid-related side effects such as nausea, vomiting, itching, constipation, and dependence associated with opioid medications used in postoperative analgesia for inguinal hernia surgeries, opioid-sparing analgesia and regional techniques are being employed. Quadratus Lumborum Blocks are being safely and easily performed and are frequently preferred in abdominal surgery due to recent advancements in trunk block techniques and ultrasound technology.

This study aims to evaluate the postoperative analgesic efficacy of adjuvant and non-adjuvant anterior Quadratus Lumborum Blocks in patients undergoing inguinal hernia surgery. The investigators predict that the analgesic efficacy of the adjuvant Quadratus Lumborum Block will be more effective and longer-lasting.

Inclusion criteria

- 18-65 years, American Society of Anesthesiologists physical statusⅠ-II -

Exclusion criteria

• local anesthetic allergy
• Infection at the procedure site
• Body Mass Index >35 kg/m2
• Anticoagulant use with bleeding disorder
• Chronic analgesia and opioid use -with mental and psychiatric disorders -