DG Journal Club
Anesthesiology. 2022 Mar
BACKGROUND Postoperative atrial fibrillation (AF) may identify patients at risk of subsequent AF, with its greater risk of stroke. We hypothesized that N-acetylcysteine mitigates inflammation and oxidative stress to reduce the incidence of postoperative AF.
METHODS In this double-blind, placebo-controlled trial, patients at high risk of postoperative AF scheduled to undergo major thoracic surgery were randomized to N-acetylcysteine plus amiodarone or placebo plus amiodarone. On arrival to the postanesthesia care unit, N-acetylcysteine or placebo bolus (intravenous 50 mg/kg then 50 mg/kg/24 h x 48 h) was administered plus amiodarone (intravenous 150 mg then 1 g/24 h x 48 h). The primary outcome was sustained AF>30 s by telemetry (first 72 h) or symptoms requiring intervention and confirmed by ECG within 7 days of surgery. Systemic markers of inflammation (interleukin-6, interleukin-8, tumor necrosis factor-N1, C-reactive protein) and oxidative stress (F2-isoprostane prostaglandin PGF2N1 [8-iso-PGF2N1], isofuran) were assessed immediately after surgery and on postoperative day 2. Patients were phoned monthly to assess the occurrence of AF in year 1.
RESULTS Among 154 patients included, postoperative AF occurred in 15 of 78 who received N-acetylcysteine (19%) and 13 of 76 who received placebo (17%) (odds ratio, 1.24; 95.1% confidence interval, 0.53-2.88; p=0.615). The trial was stopped at the interim analysis because of futility. Three of the 28 patients with postoperative AF (11%) were discharged in AF. Regardless of treatment at 1 year, 7 of 28 patients with postoperative AF (25%) had recurrent episodes of AF. Inflammatory and oxidative stress markers were similar between groups.
CONCLUSIONS Dual therapy comprising N-acetylcysteine plus amiodarone did not reduce the incidence of postoperative AF or markers of inflammation and oxidative stress early after major thoracic surgery, compared with amiodarone alone. Recurrent AF episodes are common among patients with postoperative AF within 1 year of major thoracic surgery.