Comparison of TLIP Block and QIP Block for Postoperative Analgesia After Lumbar Spine Surgery

Patients undergoing elective lumbar discectomy at up to two levels, ASA physical status I-II, aged 18-65 years, who receive either a classic TLIP block or a QIP block as part of routine clinical anesthesia practice will be included in this prospective observational study. The choice of block technique is determined solely by the treating anesthesiologist's routine practice, not by study allocation. Both blocks are performed under ultrasound guidance at the end of surgery, before emergence from anesthesia, using bilateral injections of 20 mL (40 mL total) of 0.25% bupivacaine. All patients receive standardized general anesthesia and a multimodal analgesic regimen (intravenous paracetamol, dexketoprofen, and tramadol as rescue analgesia for VAS ≥ 4). Outcomes recorded include total opioid consumption in the first 24 postoperative hours, time to first opioid request, VAS pain scores at PACU (0h), 1, 2, 4, 8, 12, and 24 hours, postoperative side effects (nausea, vomiting, pruritus, sedation, hypotension), and block-related complications (hematoma, local anesthetic systemic toxicity, infection).

Inclusion criteria

• Aged 18-65 years
• ASA physical status I-II
• Undergoing elective lumbar discectomy at up to two spinal levels under general anesthesia
• Receiving classic TLIP block or QIP block for postoperative analgesia as part of routine clinical practice

Exclusion criteria

• Hypersensitivity or allergy to study medications
• Coagulopathy
• Infection at the injection site
• Severe neurological deficit
• Chronic opioid use
• Advanced hepatic or renal failure
• Obesity (BMI >35 kg/m2)
• Pregnancy
• ASA physical status III-IV
• Mental retardation
• Inability to provide informed consent