Anaemia in Defects in Growth Exemplified by Very Low Birth Weight Infants
Very low birth weight infants commonly become anaemic through immature haematopoiesis and iatrogenic blood losses. The point at which oxygen delivery to the tissues becomes haemoglobin limited varies with the degree of cardio-respiratory instability and postnatal age, and very low birth weight infants can tolerate lower haemoglobin levels than the normal range following birth at term. The pathological burden of anaemia in very low birth weight infants can be reduced by techniques that limit losses through phlebotomy and placental transfusion at birth. A slight wait before clamping the umbilical cord or milking of the umbilical cord at birth enables an infant to inherit a higher circulating blood volume. This can reduce the need for donor red cell transfusions and affords manifold benefits to the early transition from intrauterine to postnatal life. The trend towards cardiovascular stability in the first days of life leads to a reduced incidence of intra-ventricular haemorrhage. The institution of practice guidelines governing early nutrition, iron supplementation and lowering the thresholds for donor red cell transfusions can safely reduce the number of donor red cell transfusions and transfusion-associated risks to very low birth weight infants. An example of such a guideline is outlined in this chapter.
KeywordsIron Supplementation Circulate Blood Volume Placenta Praevia Tissue Oxygen Delivery Placental Transfusion
Serious Hazards of Transfusion Scheme
The authors thank Thomas Brune for his permission to reproduce Fig. 24.1. We would like to express our gratitude to Sue Clayton, clinical librarian, for her help with the literature search.