Opioid saving strategy: bilateral single-site thoracic paravertebral block in right lobe donor hepatectomy.

BACKGROUND AND OBJECTIVES Postoperative analgesia after hepatectomy remains a challenge, mainly because of limited therapeutic index of the conventional opioids. The aim of this study is to evaluate the efficacy of bilateral single-site thoracic paravertebral block for the management of postoperative pain following right lobe donor hepatectomy (RLDH) using a prospective, randomized and controlled study design. METHODS Twenty four adult patients, aged 18-50 years, ASA-I-II, of both sexes scheduled for right lobe donor hepatic resection, were enrolled in this study. Patients were randomly allocated into 2 equal groups of 12 patients each. Before induction of general anesthesia, all patients received bilateral single-site thoracic paravertebral injection at the level of T7-8 in the sitting position. Patients of Group B were injected with 25 mL of bupivacaine 0.25% with epinephrine 1:200.000 on each side. Patients of Group P were injected with 25 mL of 0.9% NaCl (placebo). General anesthesia was standardized in all patients. Postoperative pain score, analgesic requirements and the incidence of postoperative nausea and vomiting were recorded. RESULTS Bilateral single-site thoracic paravertebral block significantly decrease the pain visual analogue score parameters. Total morphine consumption in the first 24 hours postoperatively was decreased by more than 50% in Group B (21.76 +/- 6.8 mg compared to 44.12 +/- 9.2 mg in Group P). There was significant prolongation in time to rescue analgesia (104.08 +/- 2.04 min in Group B, and 31.5 +/- 6.14 min in Group P). Postoperative nausea and vomiting was significantly less in the active Group B when compared to the controlled Group P. CONCLUSION Bilateral single-site thoracic paravertebral block is easy, safe and efficient technique for postoperative pain management in patients undergoing right lobe donor hepatectomy.