Clonidina como adjuvante da lidocaína na analgesia pós- toracotomia via bloqueio de nervo intercostal.

Abstract

Introduction: Acute pain that presents after thoracic surgery involving thoracotomy has a great impact in the surgical patient’s quality of life, and there are several trials comparing post-thoracotomy analgesia techniques. Clonidine, as an adjuvant to local anesthetics, extends and improves analgesia in several procedures. Purpose: Our aim was to assess the efficacy of clonidine as an adjuvant for lidocaine in intercostal nerve block on postoperative pain. Methods: randomized, double-blind, controlled trial, in which individuals have been allocated into two groups by the drawing of alpha-numeric codes which have been generated by a computer program. The trial has been performed at the Hospital Regional de Emergência e Trauma Dom Luiz Gonzaga Fernandes of Campina Grande(HRETDLGF-CG), during the period between August of 2013 and May of 2014. Participants: 58 patients were considered eligible by the inclusion criteria and submitted to tube thoracostomy with previous intercostal nerve block. Intervention: Intercostal nerve block was performed prior to surgery using either 2 mililiters of 2% lidocaine with 1 mililiter of clonidine (150 micrograms) or 0,9% saline. Primary Outcome: Improvement of at least 50% of the pain intensity as measured by the Visual Analog Scale (VSA) in 0, 6, 12, 24 and 48 hours post-operatively. Secondary Outcomes: Improvement of the pain in 0, 6, 12, 24 and 48 hours post-procedure, as measured by the VSA. Results: 29 patients were randomized in each group: a control group and an experimental group, but after follow-up losses, the experimental group lost 1 individual. There was no statistically significant difference between the groups concerning pain scores at 0, 6, 12, 24 or 48 hours post-procedure or improvement of at least 50% of the VSA at 0, 6, 12, 24 or 48 hours post-intercostal nerve block. Conclusion: It was not observed superiority of adding clonidine as an adjuvant for intercostal nerve block on patients submitted to tube thoracostomy. However, more trials are necessary to determine the real efficacy of clonidine as an adjuvant in analgesia via peripheral nerve block. This trial was registered in the REBEC (Brazilian rial Register) Platform, under the Trial Universal Number U1111-1171-0186. This project was financed with own resources, there being no conflict of interest to declare.