Abstract：
BACKGROUND: Unfractionated heparin (UFH) is used in most centres for extracorporeal membrane oxygenation (ECMO) anticoagulation. When standard doses do not achieve desired target values, heparin resistance is reported, most commonly defined as doses of UFH >35,000 IU/day.
OBJECTIVE: To study the incidence of heparin resistance and its association with thromboembolic complications in patients requiring ECMO support.
METHODS: In this observational cohort study, we included adults who received venovenous (VV), venoarterial (VA) ECMO, and extracorporeal CO2-removal (ECCO2R) between January 2010 and May 2022. Main risk factor was heparin resistance (UFH >35,000 IU/day or >20 IU/kg/h), the outcome was thromboembolism. Multivariable Poisson regression was used to estimate the effects of heparin resistance, adjusted for several clinical variables on the thromboembolism rate per 100 ECMO patient-days.
RESULTS: Of the 197 patients included, 33 (16.8%) required UFH >35,000 IU/day, and 14 (7.1%) required >20 IU/kg/h. Thromboembolic complications occurred at a rate of 5.89/100 ECMO days. Heparin resistance was not associated with thromboembolic events (incidence rate ratio (IRR) 0.93, 95% confidence interval (CI) 0.14 to 5.82), whereas COVID-19 (IRR 2.33, CI 1.4 to 3.96, p<0.001) and ECMO type (VA ECMO: IRR 2.29, CI 1.34 to 3.92, p=0.002; ECCO2R: IRR 2.89, CI 1.46 to 5.59, p=0.002; reference VV ECMO) were significantly associated with the risk of thromboembolic events.
CONCLUSIONS: A significant proportion of patients fulfilled the common definition of heparin resistance. However, this did not influence the occurrence of thromboembolic events.
OBJECTIVE: To study the incidence of heparin resistance and its association with thromboembolic complications in patients requiring ECMO support.
METHODS: In this observational cohort study, we included adults who received venovenous (VV), venoarterial (VA) ECMO, and extracorporeal CO2-removal (ECCO2R) between January 2010 and May 2022. Main risk factor was heparin resistance (UFH >35,000 IU/day or >20 IU/kg/h), the outcome was thromboembolism. Multivariable Poisson regression was used to estimate the effects of heparin resistance, adjusted for several clinical variables on the thromboembolism rate per 100 ECMO patient-days.
RESULTS: Of the 197 patients included, 33 (16.8%) required UFH >35,000 IU/day, and 14 (7.1%) required >20 IU/kg/h. Thromboembolic complications occurred at a rate of 5.89/100 ECMO days. Heparin resistance was not associated with thromboembolic events (incidence rate ratio (IRR) 0.93, 95% confidence interval (CI) 0.14 to 5.82), whereas COVID-19 (IRR 2.33, CI 1.4 to 3.96, p<0.001) and ECMO type (VA ECMO: IRR 2.29, CI 1.34 to 3.92, p=0.002; ECCO2R: IRR 2.89, CI 1.46 to 5.59, p=0.002; reference VV ECMO) were significantly associated with the risk of thromboembolic events.
CONCLUSIONS: A significant proportion of patients fulfilled the common definition of heparin resistance. However, this did not influence the occurrence of thromboembolic events.
摘要：
背景：普通肝素（UFH）在大多数中心用于体外膜氧合（ECMO）抗凝。当标准剂量未达到预期目标值时，据报道，肝素耐药，最常见的定义为UFH>35,000IU/天的剂量。
目的：研究需要ECMO支持的患者肝素抵抗的发生率及其与血栓栓塞并发症的关系。
方法：在这项观察性队列研究中，我们包括接受静脉静脉（VV）的成年人，静脉动脉（VA）ECMO，2010年1月至2022年5月之间的体外二氧化碳去除(ECCO2R)。主要危险因素是肝素抵抗（UFH>35,000IU/天或>20IU/kg/h），结果是血栓栓塞.多变量泊松回归用于估计肝素抵抗的影响，对每100例ECMO患者-日的血栓栓塞率的几个临床变量进行了调整。
结果：在197名患者中，33（16.8%）需要UFH>35,000IU/天，14(7.1%)需要>20IU/kg/h。血栓栓塞并发症的发生率为5.89/100ECMO天。肝素抵抗与血栓栓塞事件无关（发生率比（IRR）0.93，95％置信区间（CI）0.14至5.82），而COVID-19（IRR2.33，CI1.4至3.96，p<0.001）和ECMO类型（VAECMO：IRR2.29，CI1.34至3.92，p=0.002；ECCO2R：IRR2.89，CI1.46至5.59，p=0.002；参考VVECMO）与血栓栓塞事件的风险显着相关。
结论：相当比例的患者符合肝素抵抗的一般定义。然而,这并不影响血栓栓塞事件的发生.
目的：研究需要ECMO支持的患者肝素抵抗的发生率及其与血栓栓塞并发症的关系。
方法：在这项观察性队列研究中，我们包括接受静脉静脉（VV）的成年人，静脉动脉（VA）ECMO，2010年1月至2022年5月之间的体外二氧化碳去除(ECCO2R)。主要危险因素是肝素抵抗（UFH>35,000IU/天或>20IU/kg/h），结果是血栓栓塞.多变量泊松回归用于估计肝素抵抗的影响，对每100例ECMO患者-日的血栓栓塞率的几个临床变量进行了调整。
结果：在197名患者中，33（16.8%）需要UFH>35,000IU/天，14(7.1%)需要>20IU/kg/h。血栓栓塞并发症的发生率为5.89/100ECMO天。肝素抵抗与血栓栓塞事件无关（发生率比（IRR）0.93，95％置信区间（CI）0.14至5.82），而COVID-19（IRR2.33，CI1.4至3.96，p<0.001）和ECMO类型（VAECMO：IRR2.29，CI1.34至3.92，p=0.002；ECCO2R：IRR2.89，CI1.46至5.59，p=0.002；参考VVECMO）与血栓栓塞事件的风险显着相关。
结论：相当比例的患者符合肝素抵抗的一般定义。然而,这并不影响血栓栓塞事件的发生.
