The efficacy of intravenous vitamin C in critically ill patients: A meta-analysis of randomized controlled trials.

Abstract

BACKGROUND & AIMS\nA large number of clinical studies have shown that intravenous vitamin C supplementation is beneficial for critically ill patients, but current research conclusions are controversial. This meta-analysis included high-quality randomized controlled trials (RCTs) to evaluate the efficacy of intravenous vitamin C in critically ill patients.\n\n\nMETHODS\nWe searched PubMed, EMBASE and the Cochrane Library from inception to August 15, 2020 to identify published reports of RCTs evaluating the role of intravenous vitamin C in critically ill patients. Risk ratios values (RRs) and 95% confidence intervals (CIs) were calculated by random-effects meta-analysis. Trial sequential analysis (TSA), meta-regression, subgroup analyses and sensitivity analyses were also performed.\n\n\nRESULTS\nOur meta-analysis included 18 RCTs involving 2001 patients (1005 with vitamin C treatment and 996 control treatment). Intravenous vitamin C administration reduced the intensive care unit (ICU) length of stay (LOS) (MD\xa0=\xa0-0.36, 95% CI:\xa0-0.60 to\xa0-0.11, P\xa0=\xa00.004) and hospital LOS (MD\xa0=\xa0-1.50, 95% CI:\xa0-2.64 to\xa0-0.35, P\xa0=\xa00.01) but had no significant effect on the longest follow-up mortality, hospital or ICU mortality and change in Sequential Organ Failure Assessment (SOFA) score. TSAs for mortality, ICU and hospital LOS were inconclusive.\n\n\nCONCLUSIONS\nIntravenous vitamin C administration may shorten ICU LOS and hospital LOS. It had no effect on mortality and organ failure. All TSAs were inconclusive, and the value of vitamin C for critically ill patients needs to be demonstrated in more high-quality RCTs.