Effectiveness of Retrolaminar Block in Lumbar Spine Fusion With Multimodal Analgesia

Effectiveness of Retrolaminar Block in Reducing Postoperative Opioid Consumption in Patients Undergoing Lumbar Spine Fusion With Multimodal Analgesia

This randomized, blinded, controlled clinical trial aims to evaluate the effectiveness of ultrasound-guided retrolaminar block in reducing postoperative opioid consumption in patients undergoing lumbar spine fusion surgery under multimodal analgesia.

The participants will:

• Be randomly assigned in a 1:1 ratio to receive either a retrolaminar block with 0.25% bupivacaine plus epinephrine or a sham block (normal saline) prior to surgical incision.
• Receive standardized multimodal analgesia.
• Have follow-up by the Acute Pain Unit during the first 3 days, to assess opioid consumption (morphine) in 24 hours, pain intensity measured by Numeric Rating Scale, quality of recovery assessed by the QoR-15 questionnaire, intraoperative blood loss, and postoperative complications.

After obtaining approval from the institutional CEC-CCSS and prospective registration of the study at clinicaltrials.org, the investigators will recruit patients who meet the inclusion criteria and provide written consent.

Inclusion Criteria:

• Adults aged 18-75 years, scheduled for lumbar spine fusion surgery by a trauma team
• American Society of Anesthesiologists (ASA) Classification I-III
• Willing and able to provide written informed consent to participate in the study.

Exclusion Criteria:

• History of chronic use of strong or weak opioids for more than 3 months.
• Diagnosis of chronic pain and treatment by a pain management team.
• ASA score greater than or equal to 4.
• Patients with prior lumbar spine surgery. Spinal instrumentation at the surgical site.
• Estimated creatinine clearance less than 60 ml/min.
• Coagulation disorder or abnormal coagulation tests.
• Infection at the surgical site.
• Weight less than 50 kg.
• Altered mental status that prevents reliable evaluation.
• Allergy to local anesthetics or analgesic drugs used in the study.
• Patients with contraindications to peripheral nerve blocks.
• Lumbar spine fixation due to oncologic disease or acute trauma.
• Use of intraoperative neuromonitoring and TIVA.