BACKGROUND Previous meta-analyses of intravenous iron supplementation for reducing red blood cell (RBC) transfusion risk after cardiac surgery were inconclusive because of limited data. This updated meta-analysis incorporates recent evidence. METHODS Major databases were searched on May 2, 2024 for randomised controlled trials comparing the incidence of RBC transfusion between adult patients receiving intravenous iron supplementation and those receiving controls (i.e. oral iron or placebo) after cardiac surgery. The secondary outcomes included the number of RBC units transfused, postoperative haemoglobin levels, iron status, complications, and length of hospital stay. Trial sequential analysis was conducted to examine the robustness of evidence. RESULTS Fourteen randomised controlled trials including 2043 subjects were identified. Intravenous iron supplementation was found to reduce the RBC transfusion risk compared with controls (relative risk 0.77, 95% confidence interval [CI] 0.65-0.91, P=0.002, n=1955, I2=61%, certainty of evidence: moderate). The trial sequential analysis supported the robustness of the evidence. Furthermore, haemoglobin levels were higher in the intravenous iron supplementation group on postoperative days 4-10 (mean difference 0.17 g dl-1, 95% CI 0.06-0.29, n=1989) and >21 days (mean difference 0.66 g/dl-1, 95% CI 0.36-0.95, n=1008). Postoperative iron status also improved with Intravenous iron supplementation, particularly on postoperative days 4-10. There were no significant differences in other outcomes, including mortality. CONCLUSIONS Intravenous iron supplementation can reduce RBC transfusion risk and improve postoperative haemoglobin level and iron status after cardiac surgery, supporting the implementation of Intravenous iron supplementation in perioperative blood management strategies. SYSTEMATIC REVIEW PROTOCOL CRD42024542206 (PROSPERO).

中文翻译：

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静脉补铁降低心脏手术后输血风险的疗效：随机对照试验的最新荟萃分析。


背景 由于数据有限，先前关于静脉补铁以降低心脏手术后红细胞 （RBC） 输注风险的荟萃分析尚无定论。这项更新的荟萃分析纳入了最新证据。方法 2024 年 5 月 2 日检索了主要数据库的随机对照试验，比较了接受静脉补铁的成年患者与心脏手术后接受对照（即口服铁剂或安慰剂）的成年患者输注红细胞的发生率。次要结局包括输注的红细胞单位数、术后血红蛋白水平、铁状况、并发症和住院时间。进行试验序贯分析以检查证据的稳健性。结果 确定了 14 项随机对照试验，包括 2043 名受试者。与对照组相比，静脉补铁可降低红细胞输注风险（相对风险 0.77,95% 置信区间 [CI] 0.65-0.91，P=0.002，n=1955，I2=61%，证据质量：中等）。试验序贯分析支持证据的稳健性。此外，静脉补铁组在术后 4-10 天 （平均差 0.17 g dl-1,95% CI 0.06-0.29，n=1989） 和 >21 天 （平均差 0.66 g/dl-1,95% CI 0.36-0.95，n=1008）血红蛋白水平较高。静脉补铁后铁状况也有所改善，尤其是在术后 4-10 天。其他结局（包括死亡率）无显著差异。 结论 静脉补铁可降低心脏手术后红细胞输注风险，改善术后血红蛋白水平和铁状况，支持在围手术期血液管理策略中实施静脉补铁。系统评价方案 CRD42024542206 （PROSPERO）。