Dexamethasone as an Adjuvant to Bupivacaine in Ultrasound-Guided Caudal Epidural Block in Lumbar Spine Decompression and Fusion Surgery

Background: Postoperative pain control is a challenging issue that greatly affects the patient outcome and satisfaction. Adding dexamethasone to bupivacaine for nerve block has been shown to improve nerve block and achieve better analgesia. Aim The current study is designed aiming to evaluate and compare the preemptive analgesic effect and duration of postoperative analgesia of caudal bupivacaine versus dexamethasone as an adjuvant in single-level lumbar decompression and instrumented posterolateral intertransverse spinal fusion. Patients and Methods: The study included 60 patients undergoing elective lumbar spine decompression and fusion, randomly assigned to receive either bupivacaine alone or bupivacaine with dexamethasone via ultrasound-guided caudal epidural block under general anesthesia. Outcomes assessed included intraoperative hemodynamics, fentanyl use, timing of first analgesia request, postoperative pain (VAS at rest and movement), patient satisfaction, and complications. The primary endpoint was total postoperative morphine consumption. Results: Both groups were matched regarding age and sex. Patients of caudal dexamethasone showed lower mean postoperative VAS starting from 6 hours postoperative till 24 hours postoperative. By the end of follow up mean VAS was 4.57 among group I patients and 3.67 among group II patients with movement and 4.07 and 3.23 at rest among both groups respectively. Group II patients also have lower postoperative total dose of morphine among group II patients (mean total dose of 1 mg) compared to group II patients who reported mean total dose of 4.13 mg of morphine with p-value < 0.001. Patient satisfaction and adverse effects were insignificantly different among both groups. Conclusion: Preemptive caudal administration of bupivacaine with dexamethasone during lumbar decompression and fusion surgery prolongs postoperative pain relief, reduces intra- and postoperative analgesic needs, and promotes earlier ambulation, without causing hemodynamic instability or additional adverse effects compared to bupivacaine alone.