Comparative Evaluation of Continuous Thoracic Paravertebral Block and Thoracic Epidural Analgesia Techniques for Post-operative Pain Relief in Patients Undergoing Open Nephrectomy: A Prospective, Randomized, Single-blind Study

BACKGROUND Open surgical procedures are associated with substantial postoperative pain; an alternative method providing adequate pain relief with minimal side effects is very much required. AIM The aim of this study was a comparative evaluation of the efficacy of continuous thoracic paravertebral block (PVB) and thoracic epidural analgesia (EA) for postoperative pain relief in patients undergoing open nephrectomy. SETTINGS AND DESIGN Prospective, randomized, and single-blind study. MATERIALS AND METHODS Sixty adult patients undergoing open nephrectomy under general anesthesia were randomized to receive a continuous thoracic epidural infusion (Group E) or continuous thoracic paravertebral infusion (Group P) with bupivacaine 0.1% with 1 μg/ml fentanyl at 7 ml/h; both infusions were started after induction of anesthesia. The primary outcome measures were postoperative pain during rest (static pain), deep inspiration, coughing, and movement (getting up from supine to sitting position); the secondary outcome measures were postoperative nausea and vomiting, requirement of rescue antiemetic, hypotension, sedation, pruritus, motor block, and respiratory depression. These were assessed till the morning of the third postoperative day. STATISTICAL ANALYSIS Results were analyzed by the one-way ANOVA, Chi-square test, and Mann-Whitney U-test. P < 0.05 was considered significant. RESULTS Both the groups were similar with regard to demographic factors (P > 0.05). The visual analog scale scores at rest, deep breathing, coughing and movement, and postoperative fentanyl consumption were similar in the two groups (P > 0.05); the incidence of side effects was also similar in the two groups (P > 0.05). CONCLUSIONS Continuous thoracic PVB is as effective as continuous thoracic EA in providing pain relief in patients undergoing open nephrectomy in the postoperative period. The side effect profile of the two techniques was also similar.