Opioid-sparing effect of erector spinae plane block and intravenous dexmedetomidine for obese patients with obstructive sleep apnea: A randomized controlled trial.

Objective: This study assessed the impact of erector spinae plane block (ESPB) and intravenous (IV) dexmedetomidine in reduction of perioperative opioid consumption following bariatric surgery and their impact on post-operative recovery, analgesia, and pulmonary functions.

Design: A randomized controlled trial.

Setting: Tanta University Hospitals, Tanta, Gharboa, Egypt.

Patients: Forty obese patients with obstructive sleep apnea syndrome (OSAS), aged 20-55 years, and eligible for bariatric surgery were included.

Interventions: Patients randomized into group I (received general anesthesia [GA] with opioid, sham ESPB, and IV normal saline) or group II (received GA [without opioid], ESPB [at T7 level] using 20 mL bupivacaine 0.25 percent and bolus IV dexmedetomidine 1 µg/kg and then 0.25 µg/kg/h).

Main Outcome Measures: Fentanyl consumption (primary outcome), sevoflurane consumption, recovery time, Visual Analog Scale (VAS), and pulmonary functions (secondary outcomes) were recorded.

Results: Perioperative fentanyl (intraoperative, post-operative, and total) consumption and sevoflurane consumption were substantially lower in group II compared to group I (p = 0.010, <0.001, <0.001, and <0.001, respectively). Moreover, recovery time was shorter in group II (p < 0.001). At 2, 4, 8, and 24 hours after surgery, group I patients had VAS values considerably higher. Relative to preoperative values, pulmonary function did not significantly alter after surgery. Oxygen desaturation was significantly lower in group II (p = 0.001).

Conclusions: The ESPB with IV dexmedetomidine is advantageous for OSAS patients having bariatric surgery as it provides anesthesia and opioid-sparing effect with short recovery, adequate analgesia, and nonsignificant complications. Yet, it had no effect on post-operative pulmonary function.