Introduction

The topic of transfusion therapy continues to be heavily researched in both the adult and pediatric populations. Ongoing research continues to look at optimal thresholds for transfusion of blood products, appropriate prophylaxis for venous thromboembolic disease and best practice for treatment of underlying coagulation disorders.

What considerations in blood transfusion and coagulation therapy differ in the child from that of the adult?

Up to fifty percent of children receive a blood transfusion during their stay in the pediatric intensive care unit and almost eighty percent of extremely low birth weight infants receive a transfusion [1][2]. Ongoing areas of research include the evaluation of appropriate transfusion triggers and thresholds, the evaluation of transfusion risks and complications, assessment of appropriate component therapy and the identification of potential blood substitutes that may mitigate the risks of transfusion.

The Transfusion Requirements in Critical Care (TRICC Trial) study is a landmark article in adult critical care that supports the institution of restrictive transfusion policies [3]. This study showed a decrease in hospital mortality rate and no difference in thirty day mortality in critically ill patients who had a restrictive transfusion threshold of 7 g/dL.

Multiple studies have been performed in children to determine the optimal timing and indications for transfusion and have formed the basis for transfusion guidelines at many centers. The Transfusion Strategies for Patients in Pediatric Intensive Care Units (TRIPICU Study) by Lacroix et al indicated that a transfusion threshold of 7 g/dL significantly decreased transfusion requirements in pediatric patients without increasing adverse effects [1].

Both differences and similarities exist regarding the treatment of anemia, venous thromboembolism and coagulation disorders among infants, children and adults. Hemoglobin synthesis and hematopoiesis vary significantly with age as does the underlying causes of anemia leading to differing transfusion thresholds. Strategies to prevent anemia are also variable. The pre-transfusion preparation of blood components varies between neonates and adults (i.e. exposure to viral antigens) since the immature immune system of the neonate may predispose them to fatal infection.

Developmental hemostasis has been studied to better understand the clotting function of the newborn since the hemostatic system changes over the first years of life. Individual plasma levels of coagulation proteins and the function of the hemostatic system vary with age. For example, children develop venous thromboembolism at a much lower rate than adults such that both the dosing and indications for thromboprophylaxis differ from adult guidelines [4]. To date, no set standard guideline has been published that applies universally to children. Medications offered for the prophylaxis and treatment of thromboembolism also vary due to age-related differences in metabolism and excretion that may require further laboratory monitoring in children. A thorough understanding of the pathophysiology of blood and coagulation disorders is important to be able to deliver care to critically ill neonates and children.

Content in this topic is referenced in SCORE Coagulation overview