Efficacy of parasternal block to decrease intraoperative opioid use in coronary artery bypass surgery via sternotomy: a randomized controlled trial

Abstract

Objective: This study aims to assess the effect of a preoperative parasternal plane block (PSB) on opioid consumption required to maintain hemodynamic stability during sternotomy for coronary artery bypass graft surgery.

Methods: This double-blind, randomized, placebo-controlled trial prospectively enrolled 35 patients scheduled for coronary artery bypass graft surgery under general anesthesia with propofol and remifentanil. Patients were randomized to receive preoperative PSB using either ropivacaine (PSB group) or saline solution (placebo group) (1:1 ratio). The primary endpoint was the maximal effect-site concentration of remifentanil required to maintain heart rate and blood pressure within the recommended ranges during sternotomy.

Results: Median maximum concentration of remifentanil necessary to maintain adequate hemodynamic status during sternotomy was significantly reduced in PSB group (4.2 (2.5-6.0) ng/mL) compared with placebo group (7.0 (5.2-8.0) ng/mL) (p=0.02). Mean maximum concentration of propofol used to control depth of anesthesia was also reduced (3.9±1.1 µg/mL vs 5.0±1.5 µg/mL, PSB vs placebo, respectively; p=0.02). This reduction in propofol consumption during sternotomy enabled a more adequate level of sedation to be maintained in patients (minimum patient state index was 11.7±8.7 in placebo group and 18.3±6.8 in PSB group; p=0.02). PSB reduced postoperative inflammatory response by limiting concentrations of proinflammatory cytokines IL-8, IL-18, IL-23, IL-33 and MCP-1 measured in the first 7-day after surgery (p<0.05).

Conclusions: Preoperative PSB reduced the maximum concentrations of remifentanil and propofol required to maintain hemodynamic stability and depth of anesthesia during sternotomy.

Trial registration number: NCT03734159.Sébastien Bloc, M.D.^1,2; Brieuc P. Pérot, Ph.D.³; Hadrien Gibert, M.D.¹; Jean-Dominique Law Koune, M.D.¹; Yannick Burg, M.D.¹; Didier Leclerc, M.D.¹; Anne-Sophie Vuitton, M.D.¹; Christophe De La Jonquière, M.D.¹; Marine Luka, L.S.³; Thierry Waldmann, M.D.⁴; Nicolas Vistarini, M.D.⁴; Stéphane Aubert, M.D.⁴; Mickaël M. Ménager, Ph.D.³; Messaouda Merzoug, Ph.D.²; Cécile Naudin, Ph.D.²; Pierre Squara, M.D.^2,5.

Keywords: anesthesia; conduction; nerve block; regional anesthesia; ultrasonography.