Carrefour de l'innovation et santé des populations, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900, rue St-Denis, porte S03-434, Montréal, QC, Canada.
Department of Anesthesiology, Centre hospitalier de l'Université de Montréal, Montréal, QC, Canada.
Can J Anaesth. 2022 Apr;69(4):438-447. doi: 10.1007/s12630-022-02197-1. Epub 2022 Feb 2.
Liver transplantation is associated with major bleeding and red blood cell (RBC) transfusions. No well-designed causal analysis on interventions used to reduce transfusions, such as an intraoperative phlebotomy, has been conducted in this population.
We conducted a historical cohort study among liver transplantations performed from July 2008 to January 2021 in a Canadian centre. The exposure was intraoperative phlebotomy. The outcomes were blood loss, perioperative RBC transfusions (intraoperative and up to 48 hr after surgery), intraoperative RBC transfusions, and one-year survival. We estimated marginal multiplicative factors (MFs), risk differences (RDs), and hazard ratios by inverse probability of treatment weighting both among treated patients and the whole population. Estimates are reported with 95% confidence intervals (CIs).
We included 679 patients undergoing liver transplantations of which 365 (54%) received an intraoperative phlebotomy. A phlebotomy did not reduce bleeding, transfusion risks, or mortality when estimated among the treated but reduced bleeding and transfusion risks when estimated among the whole population (MF, 0.85; 95% CI, 0.72 to 0.99; perioperative RD, -15.2%; 95% CI, -26.1 to -0.8; intraoperative RD, -14.7%; 95% CI, -23.2 to -2.8). In a subgroup analysis on 584 patients with end-stage liver disease, slightly larger effects were observed on both transfusion risks when estimated among the whole population while beneficial effects were observed on the intraoperative transfusion risk when estimated among the treated population.
The use of intraoperative phlebotomy was not consistently associated with better outcomes in all targets of inference but may improve outcomes among the whole population.
www.
gov (NCT04826666); registered 1 April 2021.
肝移植会导致大量出血和红细胞（RBC）输注。在该人群中，尚未对用于减少输血的干预措施（如术中采血）进行精心设计的因果分析。
我们在加拿大的一家中心进行了一项 2008 年 7 月至 2021 年 1 月期间进行的肝移植的历史队列研究。暴露因素为术中采血。结局包括失血量、围手术期 RBC 输注（术中及术后 48 小时内）、术中 RBC 输注以及一年生存率。我们通过逆概率治疗加权法（Inverse Probability of Treatment Weighting，IPTW）分别在治疗患者和整个人群中估计边缘乘法因子（Marginal Multiplicative Factors，MFs）、风险差异（Risk Differences，RDs）和危险比（Hazard Ratios，HRs）。结果以 95%置信区间（Confidence Intervals，CIs）报告。
我们纳入了 679 例肝移植患者，其中 365 例（54%）接受了术中采血。在治疗患者中，采血并未降低出血、输血风险或死亡率，而在整个人群中，采血降低了出血和输血风险（MF，0.85；95%CI，0.72 至 0.99；围手术期 RD，-15.2%；95%CI，-26.1 至-0.8；术中 RD，-14.7%；95%CI，-23.2 至-2.8）。在 584 例终末期肝病患者的亚组分析中，当在整个人群中进行估计时，输血风险的效果略大，而当在治疗人群中进行估计时，术中输血风险则有获益。
术中采血在所有推断目标中并不始终与更好的结果相关，但在整个人群中可能改善结局。
www.（NCT04826666）；2021 年 4 月 1 日注册。
