Perioperative omega-3 fatty acids fail to confer protection in liver surgery: Results of a multicentric, double-blind, randomized controlled trial.

BACKGROUND & AIMS: In a variety of animal models, omega-3 polyunsaturated fatty acids (Ω3-FAs) conferred strong protective effects, alleviating hepatic ischemia/reperfusion injury and steatosis, as well as enhancing regeneration after major tissue loss. Given these benefits along with its safety profile, we hypothesized that perioperative administration of Ω3-FAs in patients undergoing liver surgery may ameliorate the postoperative course. The aim of this study was to investigate the perioperative use of Ω3-FAs to reduce postoperative complications after liver surgery. METHODS: Between July 2013 and July 2018, we carried out a multicentric, double-blind, randomized, placebo-controlled trial designed to test whether 2 single intravenous infusions of Omegaven® (Ω3-FAs) vs. placebo may decrease morbidity. The primary endpoints were postoperative complications by severity (Clavien-Dindo classification) integrated within the comprehensive complication index (CCI). RESULTS: A total of 261 patients (132 in the Omegaven and 129 in the placebo groups) from 3 centers were included in the trial. Most cases (87%, n = 227) underwent open liver surgery and 56% (n = 105) were major resections (≥3 segments). In an intention-to-treat analysis including the dropout cases, the mortality rate was 4% and 2% in the Omegaven and placebo groups (odds ratio0.40;95% CI 0.04-2.51; p = 0.447), respectively. Any complications and major complications (Clavien-Dindo ≥ 3b) occurred in 46% vs. 43% (p = 0.709) and 12% vs. 10% (p = 0.69) in the Omegaven and placebo groups, respectively. The mean CCI was 17 (±23) vs.14 (±20) (p = 0.417). An analysis excluding the dropouts provided similar results. CONCLUSIONS: The routine perioperative use of 2 single doses of intravenous Ω3-FAs (100 ml Omegaven) cannot be recommended in patients undergoing liver surgery (Grade A recommendation). LAY SUMMARY: Despite strong evidence of omega-3 fatty acids having liver-directed, anti-inflammatory and pro-regenerative action in various rodent models, 2 single omega-3 fatty acid infusions given to patients before and during liver surgery failed to reduce complications. Because single omega-3 fatty acid infusions failed to confer liver protection in this trial, they cannot currently be recommended. TRIAL REGISTRATION: ClinicalTrial.gov: ID: NCT01884948; Institution Ethical Board Approval: KEK-ZH-Nr. 2010-0038; Swissmedic Notification: 2012DR3215.

"A randomized, double-blind study of the effects of omega-3 fatty acids (Omegaven) on outcome after major liver resection".

BACKGROUND: The body is dependent on the exogenous supply of omega-3 polyunsaturated fatty acids (n3-PUFA). These essential fatty acids are key players in regulating metabolic signaling but also exert anti-inflammatory and anti-carcinogenic properties. The liver is a major metabolic organ involved in fatty acid metabolism. Under experimental conditions, n3-PUFA exert beneficial effect on hepatic steatosis, regeneration and inflammatory insults such as ischemic injury after surgery. Some of these effects have also been observed in human subjects. However, it is unclear whether perioperative administration of n3-PUFA is sufficient to protect the liver from ischemic injury. Therefore, we designed a randomized controlled trial (RCT) assessing n3-PUFA (pre-) conditioning strategies in patients scheduled for liver surgery. METHODS/DESIGN: The Omegaven trial is a multi-centric, double-blind, randomized, placebo- controlled trial applying two single doses of Omegaven or placebo on 258 patients undergoing major liver resection. Primary endpoints are morbidity and mortality one month after hospital discharge, defined by the Clavien- Dindo classification of surgical complications (Ann Surg 240(2):205-13, 2004) as well as the Comprehensive Complication Index (CCI) (Ann Surg 258(1):1-7, 2013). Secondary outcome variables include length of Intensive Care Unit (ICU) and hospital stay, postoperative liver function tests, fatty acid and eicosanoid concentration, inflammatory markers in serum and in liver tissue. An interim analysis is scheduled after the first 30 patients per randomization group. DISCUSSION: Long-term administration of n3-PUFA have a beneficial effect on metabolism and hepatic injury. Patients often require surgery without much delay, thus long-term n3-PUFA uptake is not possible. Also, lack of compliance may lead to incomplete n3-PUFA substitution. Hence, perioperative Omegaven™ may provide an easy and controllable way to ensure hepaative application of tic protection. TRIAL REGISTRATION: ClinicalTrial.gov: ID: NCT01884948 , registered June 14, 2013; Institution Ethical Board Approval: KEK-ZH-Nr. 2010-0038; Swissmedic Notification: 2012DR3215.