Figueroa Villalba Cristina A, Saifee Nabiha H, Chandler Wayne L
From the Department of Laboratory Medicine, Yale School of Medicine, New Haven, Connecticut.
Department of Laboratory Medicine and Pathology, Seattle Children's Hospital, Seattle, Washington.
ASAIO J. 2024 Dec 1;70(12):1102-1108. doi: 10.1097/MAT.0000000000002265. Epub 2024 Jun 30.
Sublethal damage to red blood cells (RBCs) during extracorporeal life support (ECLS) may lead to RBC loss. Using flow cytometry, phosphatidylserine-positive (PhS+) RBCs and RBC extracellular vesicles were quantified as measures of sublethal RBC injury in 41 pediatric ECLS runs, stored RBC units, and normal adult subjects. We estimated the clearance half-life of PhS+ RBCs and compared the rates of RBC loss during pediatric ECLS due to phlebotomy, intravascular hemolysis, and extravascular clearance of PhS+ RBCs. Extracorporeal life support patients had 0.9% PhS+ RBCs, sixfold higher than normal subjects ( p < 0.0001). Phosphatidylserine-positive RBCs were increased in stored RBC units (twofold in whole blood derived units, p = 0.0013; 12-fold in apheresis RBC units, p < 0.0001). Phosphatidylserine-positive RBCs were cleared with an average half-life of 15 hours. During ECLS, PhS+ RBC clearance accounted for 7% of RBC loss (1-60%), phlebotomy 12%, and intravascular hemolysis 12%. Increasing PhS+ RBCs occurred in 40% of patients that died on ECLS. Red blood cell extracellular vesicles, another marker of red cell injury/activation, were elevated fivefold during ECLS. Phosphatidylserine exposure on RBCs is increased during ECLS, marking these cells for extravascular clearance with a half-life of ~15 hours and accounting for ~7% of RBC loss.
体外生命支持（ECLS）期间红细胞（RBC）受到的亚致死性损伤可能导致红细胞丢失。我们采用流式细胞术对41例儿科ECLS治疗过程、储存红细胞单位及正常成人受试者中的磷脂酰丝氨酸阳性（PhS+）红细胞和红细胞细胞外囊泡进行定量，作为亚致死性红细胞损伤的指标。我们估计了PhS+红细胞的清除半衰期，并比较了儿科ECLS期间因放血、血管内溶血和PhS+红细胞血管外清除导致的红细胞丢失率。接受体外生命支持的患者有0.9%的PhS+红细胞，比正常受试者高6倍（p<0.0001）。储存红细胞单位中磷脂酰丝氨酸阳性红细胞增加（全血来源单位增加2倍，p=0.0013；单采红细胞单位增加12倍，p<0.0001）。磷脂酰丝氨酸阳性红细胞的平均清除半衰期为15小时。在ECLS期间，PhS+红细胞清除占红细胞丢失的7%（1%-60%），放血占12%，血管内溶血占12%。40%在ECLS治疗期间死亡的患者出现PhS+红细胞增加。红细胞细胞外囊泡是红细胞损伤/激活的另一个标志物，在ECLS期间升高了5倍。ECLS期间红细胞上磷脂酰丝氨酸的暴露增加，标记这些细胞以便进行血管外清除，半衰期约为15小时，占红细胞丢失的约7%。
