Use of postoperative analgesia in kidney transplant recipients has always been challenging due to several issues: potential nephrotoxicity of nonsteroidal anti- inflammatory drugs and the reduced clearance of morphine metabolites due to transient renal impairment.Moreover, many patients with end-stage renal disease on dialysis are hepatitis C or hepatitis B virus positive, and the use of other effective analgesics, such as acetaminophen, is limited.The use of regional analgesia methods for postoperative analgesia can also be a useful option for more adequate control in these patients. Currently, methods of fascial trunk nerve blocks (including rectus sheath block, different types of transversus abdominis plane block, and erector spinae plane [ESP] block) have been shown to be effective components of multimodal anesthesia in various fields of surgery.In this study, investigators evaluated the effectiveness of ESP block in the postoperative period after kidney transplant.The aim of this prospective, randomized controlled trial is to evaluate the effects of erector spinae plane block on postoperative analgesia quality, opioid consumption, and side effect profile in kidney transplant patients.The study included a total of 40 patients aged 18-65 years with ASA physical status II-III who were scheduled for elective kidney transplantation. All patients received standard general anesthesia. Anesthesia induction was achieved with propofol (2-2.5 mg/kg), fentanyl (1-2 µg/kg), and rocuronium (0.6 mg/kg). Anesthesia maintenance was provided with 6% desflurane and a 50% oxygen-air mixture.ESPB Group: USG-guided unilateral ESP block at T9 level (0.25% bupivacaine 20 ml)

• Control Group: no block applied
• All patients received standard postoperative analgesia protocol. Intravenous paracetamol (1 g/8 hours) was given. Intravenous tramadol (100 mg) was administered as rescue analgesic when VAS ≥ 4.

Inclusion Criteria:

• All patients had end-stage renal disease due to chronic glomerulonephritis _ physical status of class 3 on American Society of Anesthesiologists classification.

Exclusion Criteria:

• ASA 4