A Comparison of Bupivacaine Instillation and Ultrasound Guided Field Block for Post-Operative Pain Relief in Inguinal Hernia Repair

Abstract

ABSTRACT:BACKGROUND: Postoperative pain is a common problem after inguinal hernia repair. Postoperative pain may delay the return to normal activity and delay hospital discharge. Various techniques have been employed to provide postoperative analgesia, by the use of regional anesthetic technique, local anesthesia or traditional analgesic technique: opiates, non-steroidal anti-inflammatory drugs (NSAIDs) or combinations.OBJECTIVE: To compare the postoperative pain relief provided by simple bupivacaine wound instillation and ultrasound guided inguinal hernia field block.PATIENT AND METHOD: A single blind, prospective, randomized controlled clinical trial for 72 male patients who were undergoing elective unilateral inguinal hernia repair. In 37 of them 10 ml of 0.5% plain bupivacaine was instilled (irrigated) into the wound by the surgeon for 1 minute. In another 35 patients, ultrasound guided field block performed using 20 ml of 0.25% plain bupivacaine at the end of surgery. Vital signs, numerical pain score and analgesia requirement were recorded at recovery (zero hour), 1st, 2nd, 4th& 8th hours postoperatively.RESULT: By applying null hypothesis, using the t-student test of two independent samples, pain score and request for analgesia show significant difference only at the first two hours with p-value <0.05, otherwise there was no significant differences in the following hours. For vital signs there was no significant difference for both groupsCONCLUSION: Bupivacaine instillation is as effective as ultrasound guided field block for inguinal hernia repair pain. We recommend this technique in places where ultrasound machine is not available especially in many developing countries.