Paravertebral block using levobupivacaine or dexmedetomidine-levobupivacaine for analgesia after cholecystectomy: a randomized double-blind trial

Abstract

Background: Thoracic paravertebral block (TPVB) has emerged as an effective and feasible mode of providing analgesia in laparoscopic cholecystectomy. Though a variety of local anaesthetic combinations are used for providing TPVB, literature is sparse on use of dexmedetomidine in TPVB. We aimed to compare levobupivacaine and levobupivacaine-dexmedetomidine combination in ultrasound guided TPVB in patients undergoing laparoscopic cholecystectomy.

Methodology: 70 ASA I/II patients, aged 18-60 years, scheduled to undergo laparoscopic cholecystectomy under general anaesthesia were enrolled and divided into two groups. Before anaesthesia induction, group A patients received unilateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml normal saline while group B patients received unilateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml solution containing dexmedetomidine 1 μg.kg^-1. Patients were monitored for pain using Numeric Rating Scale (NRS) at rest, on movement, coughing and comfort scores post surgery. Total analgesic consumption in first 48 hour postoperative period, time to first request analgesic and pain scores were recorded.

Results: Total amount of rescue analgesia (injection tramadol plus injection tramadol intravenous equivalent dose) consumed during 48 hours postoperatively in group A was 146.55 mg while in group B was 111.30 mg (p = 0.026). Mean time for demanding rescue analgesia was 273 minutes in group A while in group B was 340 minutes (p = 0.00).

Conclusion: TPVB using dexmedetomidine 1 μg.kg^-1 added to levobupivacaine 0.25% in patients undergoing laparoscopic cholecystectomy significantly reduced total analgesic consumption in first 48 hours and provided longer duration of analgesia postoperatively compared to levobupivacaine 0.25% alone.

Keywords: Dexmedetomidine; Laparosopic cholecystectomy; Levobupivacaine; Postoperative analgesia; Thoracic paravertebral block.