Foreman C, Gruenwald C, West L
Cardiovascular Perfusion Department, The Hospital for Sick Children, Toronto, Canada.
Perfusion. 2004 Jan;19(1):69-72. doi: 10.1191/0267659104pf708oa.
Infants with fatal cardiac disease often die awaiting transplantation because of the shortage of donor hearts. The Hospital for Sick Children (HSC), Toronto, Canada, has researched and applied the concept of crossing the blood group compatibility barrier. Heart transplantation at HSC unrestricted by ABO compatibility greatly contributed to decreasing the mortality rate among infants on the waiting list from 58% to 10%. From January 1996 to January 2002, 16 infants less than 14 months of age received ABO-incompatible heart transplants at our institution. The cardiopulmonary bypass (CPB) circuit is primed with additional volume to replace the patient's blood volume. Packed red blood cells (PRBC) used in priming must be ABO-compatible with the recipient. All plasma components and platelets must contain no anti-A or anti-B antibodies to donor or recipient. CPB is initiated and the patient's venous blood is collected into a transfusion bag and sent to the blood bank. The total amount collected should be one and a half to two times the patient's blood volume. The plasma is separated and discarded, returning only the PRBC, thus reducing the concentration of circulating antibodies to blood group antigens. Our team has experienced an 87% survival rate with this technique. The success is believed to be associated with the recipients' immunologic immaturity. Newborns do not produce isohemagglutinins, and serum anti-A and anti-B antibody titers usually remain low until 12-14 months of age. The complement system is not fully developed, therefore, the mediators of hyperacute rejection are absent during early infancy. Heart transplantation unrestricted by the need for ABO compatibility would effectively expand the available donor pool and decrease waiting times.
患有致命性心脏病的婴儿常常因供体心脏短缺而在等待移植的过程中死亡。加拿大多伦多病童医院（HSC）研究并应用了跨越血型相容性障碍的概念。HSC不受ABO血型相容性限制的心脏移植极大地有助于将等待名单上婴儿的死亡率从58%降至10%。1996年1月至2002年1月，我们机构有16名14个月以下的婴儿接受了ABO血型不相容的心脏移植。体外循环（CPB）回路预充额外的容量以替代患者的血容量。预充中使用的浓缩红细胞（PRBC）必须与受者的ABO血型相容。所有血浆成分和血小板必须不含有针对供体或受者的抗A或抗B抗体。启动CPB，将患者的静脉血收集到一个输血袋中并送往血库。收集的总量应为患者血容量的1.5至2倍。分离并丢弃血浆，仅回输PRBC，从而降低循环抗体对血型抗原的浓度。我们的团队使用该技术的存活率为87%。这种成功被认为与受者的免疫不成熟有关。新生儿不产生同种血凝素，血清抗A和抗B抗体滴度通常在12至14个月龄之前一直保持较低水平。补体系统尚未完全发育，因此，在婴儿早期不存在超急性排斥反应的介质。不受ABO血型相容性需求限制的心脏移植将有效地扩大可用供体库并减少等待时间。
