Abstract：
BACKGROUND: The hemoglobin value to trigger RBC transfusion for patients receiving venovenous extracorporeal membrane oxygenation (ECMO) is controversial. Previous guidelines recommended transfusing to a normal hemoglobin level, but recent studies suggest that more RBC transfusions are associated with increased adverse outcomes.
OBJECTIVE: Is implementation of different institutional RBC transfusion thresholds for patients receiving venovenous ECMO associated with changes in RBC use and patient outcomes?
METHODS: This single-center retrospective study of patients receiving venovenous ECMO used segmented regression to test associations between implementation of institutional transfusion thresholds and trends in RBC use. Associations with secondary outcomes, including in-hospital survival, also were assessed.
RESULTS: The study included 229 patients: 91 in the no threshold cohort, 48 in the hemoglobin < 8 g/dL cohort, and 90 in the hemoglobin < 7 g/dL cohort. Despite a decrease in number of RBC units transfused per day of ECMO support after implementation of different thresholds (mean ± SD: 0.6 ± 1.0 in the no threshold cohort, 0.3 ± 0.8 in the hemoglobin < 8 g/dL cohort, and 0.3 ± 1.1 in the hemoglobin < 7 g/dL cohort; P < .001), segmented regression showed no association between implementation of transfusion thresholds and changes in trends in number of RBC units per day of ECMO. We observed an increased hazard of death in the no threshold cohort compared with the hemoglobin < 8 g/dL cohort (adjusted hazard ratio [aHR], 2.08; 95% CI, 1.12-3.88) and in the hemoglobin < 7 g/dL cohort compared with the hemoglobin < 8 g/dL cohort (aHR, 1.93; 95% CI, 1.02-3.62). No difference was found in the hazard of death between the no threshold and hemoglobin < 7 g/dL cohorts (aHR, 1.08; 95% CI, 0.69-1.69).
CONCLUSIONS: We observed a decrease in number of RBC units per day of ECMO over time, but changes were not associated temporally with implementation of transfusion thresholds. A transfusion threshold of hemoglobin < 8 g/dL was associated with a lower hazard of death, but these findings are limited by study methodology. Further research is needed to investigate optimal RBC transfusion practices for patients supported with venovenous ECMO.
OBJECTIVE: Is implementation of different institutional RBC transfusion thresholds for patients receiving venovenous ECMO associated with changes in RBC use and patient outcomes?
METHODS: This single-center retrospective study of patients receiving venovenous ECMO used segmented regression to test associations between implementation of institutional transfusion thresholds and trends in RBC use. Associations with secondary outcomes, including in-hospital survival, also were assessed.
RESULTS: The study included 229 patients: 91 in the no threshold cohort, 48 in the hemoglobin < 8 g/dL cohort, and 90 in the hemoglobin < 7 g/dL cohort. Despite a decrease in number of RBC units transfused per day of ECMO support after implementation of different thresholds (mean ± SD: 0.6 ± 1.0 in the no threshold cohort, 0.3 ± 0.8 in the hemoglobin < 8 g/dL cohort, and 0.3 ± 1.1 in the hemoglobin < 7 g/dL cohort; P < .001), segmented regression showed no association between implementation of transfusion thresholds and changes in trends in number of RBC units per day of ECMO. We observed an increased hazard of death in the no threshold cohort compared with the hemoglobin < 8 g/dL cohort (adjusted hazard ratio [aHR], 2.08; 95% CI, 1.12-3.88) and in the hemoglobin < 7 g/dL cohort compared with the hemoglobin < 8 g/dL cohort (aHR, 1.93; 95% CI, 1.02-3.62). No difference was found in the hazard of death between the no threshold and hemoglobin < 7 g/dL cohorts (aHR, 1.08; 95% CI, 0.69-1.69).
CONCLUSIONS: We observed a decrease in number of RBC units per day of ECMO over time, but changes were not associated temporally with implementation of transfusion thresholds. A transfusion threshold of hemoglobin < 8 g/dL was associated with a lower hazard of death, but these findings are limited by study methodology. Further research is needed to investigate optimal RBC transfusion practices for patients supported with venovenous ECMO.
摘要：
背景：对于接受静脉体外膜氧合（VV-ECMO）的患者，触发红细胞（RBC）输血的血红蛋白值存在争议。以前的指南建议输血至正常血红蛋白，但最近的研究表明,更多的RBC输血与不良结局增加相关.
目的：对接受VV-ECMO的患者实施不同的机构RBC输血阈值是否与RBC利用和患者预后的变化有关？
方法：对接受VV-ECMO的患者进行单中心回顾性研究，使用分段回归测试机构输血阈值的实施与RBC利用趋势之间的关联。与次要结果的关联，包括住院期间的生存,也进行了评估。
结果：该研究包括229例患者：“无阈值（NT）”队列中的91例，“血红蛋白<8g/dL（<8g/dL）”队列中48人，“血红蛋白<7g/dL（<7g/dL）”队列中90人。尽管在实施不同阈值后，RBC/ECMO日有所减少，(平均值+/-标准差；NT队列中的0.6+/-1.0，<8g/dL队列中的0.3+/-0.8，在<7g/dL队列中，为0.3+/-1.1，p<0.001)，分段回归显示,实施输血阈值与RBC/ECMO日的变化趋势无相关性.我们观察到与<8g/dL队列相比，NT队列的死亡风险增加（aHR：2.08，95％CI：1.12-3.88），与<8g/dL队列相比，<7g/dL队列（aHR：1.93，95%CI：1.02-3.62）。NT和<7g/dL队列之间的死亡风险没有差异（aHR：1.08，95％CI：0.69-1.69）。
结论：我们观察到RBC/ECMO日随着时间的推移而减少，但改变在时间上与输血阈值的实施无关.血红蛋白的输血阈值<8g/dL与较低的死亡风险相关。但是这些发现受到研究方法的限制。需要进一步的研究来调查接受VV-ECMO支持的患者的最佳红细胞输血实践。
目的：对接受VV-ECMO的患者实施不同的机构RBC输血阈值是否与RBC利用和患者预后的变化有关？
方法：对接受VV-ECMO的患者进行单中心回顾性研究，使用分段回归测试机构输血阈值的实施与RBC利用趋势之间的关联。与次要结果的关联，包括住院期间的生存,也进行了评估。
结果：该研究包括229例患者：“无阈值（NT）”队列中的91例，“血红蛋白<8g/dL（<8g/dL）”队列中48人，“血红蛋白<7g/dL（<7g/dL）”队列中90人。尽管在实施不同阈值后，RBC/ECMO日有所减少，(平均值+/-标准差；NT队列中的0.6+/-1.0，<8g/dL队列中的0.3+/-0.8，在<7g/dL队列中，为0.3+/-1.1，p<0.001)，分段回归显示,实施输血阈值与RBC/ECMO日的变化趋势无相关性.我们观察到与<8g/dL队列相比，NT队列的死亡风险增加（aHR：2.08，95％CI：1.12-3.88），与<8g/dL队列相比，<7g/dL队列（aHR：1.93，95%CI：1.02-3.62）。NT和<7g/dL队列之间的死亡风险没有差异（aHR：1.08，95％CI：0.69-1.69）。
结论：我们观察到RBC/ECMO日随着时间的推移而减少，但改变在时间上与输血阈值的实施无关.血红蛋白的输血阈值<8g/dL与较低的死亡风险相关。但是这些发现受到研究方法的限制。需要进一步的研究来调查接受VV-ECMO支持的患者的最佳红细胞输血实践。
