Division of Cardiac Surgery, Henry Ford Hospital, Detroit, Mich 48202, USA.
J Thorac Cardiovasc Surg. 2012 Jan;143(1):178-85. doi: 10.1016/j.jtcvs.2011.09.015. Epub 2011 Oct 19.
Perioperative red blood cell transfusion is associated with increased morbidity and mortality after coronary artery bypass grafting (CABG). Whether transfusion is a cause of these outcomes or serves as a surrogate for a high-risk patient population remains uncertain. This retrospective study tested the hypothesis that increased preoperative risk profile of patients receiving transfusion would explain the relationship between red blood cell transfusion and operative mortality in isolated CABG.
A total of 31,818 patients undergoing isolated CABG were entered into a statewide collaborative database between January 2006 and June 2010. With the Society of Thoracic Surgeons risk calculator, patient cohorts were stratified into 4 groups by predicted risk of mortality (PROM) of less than 2%, 2% to 5%, more than 5% to 10% and more than 10%. The association between blood transfusion and mortality was tested at each stratum with a χ(2) test. A Breslow-Day test for homogeneity of odds ratios was used to test whether the 4 odds ratios of the strata were similar, and a Cochran-Mantel-Haenszel test was used to test the association between blood transfusion and mortality while controlling for predicted risk mortality strata.
In all, 17,720 (55.7%) of all patients were transfused during the hospitalization. Incidence of transfusion increased stepwise with risk level; 93.3% of patients with PROM greater than 10% received blood. Operative mortality was 2.1% overall, 0.6% among the 44.3% of patients who were not transfused, and 3.3% in the transfused group (odds ratio, 6.19; P < .0001). The association between blood transfusion and mortality was significant within each predicted risk stratum. Increased mortality associated with transfusion was statistically equivalent across all predicted risk strata (P = .1778). The association between blood transfusion and mortality for all patients lessened somewhat when controlling for PROM (odds ratio, 2.99 vs 6.19), yet remained highly significant (P < .0001).
The association between red blood cell transfusion and mortality after CABG is highly significant and independent of increased preoperative risk status. The correlation persists after controlling for increased PROM.
围手术期输红细胞与冠状动脉旁路移植术（CABG）后的发病率和死亡率增加有关。输血是否是这些结果的原因，或者是否是高危患者人群的替代指标，目前仍不确定。这项回顾性研究检验了以下假设：接受输血的患者术前风险状况增加将解释 CABG 中红细胞输血与手术死亡率之间的关系。
2006 年 1 月至 2010 年 6 月，在全州合作数据库中纳入了 31818 例行单纯 CABG 的患者。使用胸外科医生协会风险计算器，根据预测死亡率（PROM）的风险将患者分为 4 组，死亡率风险小于 2%、2%至 5%、大于 5%至 10%和大于 10%。用卡方检验检验输血与死亡率之间的关联。用 Breslow-Day 检验检验各分层的优势比是否相似，用 Cochran-Mantel-Haenszel 检验在控制预测死亡率分层的情况下检验输血与死亡率之间的关联。
总共，所有患者中有 17720 例（55.7%）在住院期间输血。输血的发生率随风险水平逐步增加；PROM 大于 10%的患者中有 93.3%接受了输血。总的手术死亡率为 2.1%，未输血患者的死亡率为 0.6%，输血患者的死亡率为 3.3%（比值比，6.19；P<0.0001）。输血与死亡率之间的关联在每个预测风险分层中均具有统计学意义。输血与死亡率之间的关联在所有预测风险分层中均具有统计学意义（P=0.1778）。在控制 PROM 后，所有患者输血与死亡率之间的关联略有减弱（比值比，2.99 比 6.19），但仍具有高度显著性（P<0.0001）。
CABG 后输血与死亡率之间的关联高度显著，且独立于术前风险状况增加。在控制 PROM 增加后，相关性仍然存在。
