Blood-component therapy in children: Case

The neonatal transfusion thresholds

The preterm neonate is the most transfused of all children, and the transfusion thresholds differ from those of the older child. The red cell transfusion is guided by the lower haemoglobin thresholds supported by the TOP trial, which found a lower threshold as safe as a higher one for the preterm infant, so this child is transfused red cells at 10 to 20 mL per kg to keep the haemoglobin above a low, gestation-specific threshold rather than to a normal value. The platelet transfusion is guided by the PlaNeT-2 MATISSE trial, which found that a lower threshold of 25 times ten to the nine per litre was safer than a higher threshold of 50, and the meta-analysis of Fustolo-Gunnink confirmed the benefit of the lower threshold. [8][9][5]

The special products for this neonate

This neonate should receive cytomegalovirus-negative components to prevent a primary cytomegalovirus infection, which can be devastating in the immunologically immature infant, and leucodepleted components are the default. The components are ABO and Rh compatible, and ideally ABO identical, and the units are given fresh to minimise the potassium load and the storage lesion. The per-kilogram dose of the red cell top-up is 10 to 20 mL per kg and the platelet transfusion is 10 to 20 mL per kg, run slowly to avoid circulatory overload in a child whose total blood volume is only about 90 millilitres per kilogram. [2]

The recognition of circulatory overload

Transfusion-associated circulatory overload is the commonest serious transfusion reaction, and the neonate is at particular risk because of the small circulating volume. The child presents with respiratory distress, hypoxia and pulmonary oedema within six hours of a transfusion given too fast or too large, and the prevention is a weight-based dose, a slow rate, and the vigilance to recognise the breathlessness early. The treatment is oxygen, sitting the child up, a diuretic, and the cessation of the transfusion. The bedside safety rests on the two-person check of identity and compatibility and on the observation of the first 15 minutes at a slow rate. [2]

The planning of future transfusions

The planning of her future transfusions looks ahead to the chronic transfusion scenario, because a child who is transfused often is at risk of alloimmunisation and iron overload. The red cells are phenotype-matched from the start to prevent the antibodies that complicate future cross-matching, the iron stores are watched as the transfusions accumulate, and the special-product flag is kept current. The aim is a child who receives the minimum necessary transfusion, safely matched and safely observed, with the alternatives of patient blood management pursued wherever the cause is treatable. [2]