Foetal haemoglobin, blood transfusion, and retinopathy of prematurity

Stutchfield et al. have recently demonstrated that low foetal haemoglobin (HbF) levels predict retinopathy of prematurity (ROP) . There is an increasing awareness that red blood cell (RBC) transfusions are independent risk factors for all prematurity-associated diseases (PAD). Since adult haemoglobin (HbA) releases oxygen more efficiently than HbF, autologous cord blood (CB) transfusion has been attempted, with limited results due to the low volume of CB collected. We have shown that allogeneic CB RBC concentrates obtained from healthy full-term babies can fulfil transfusion requirements of preterm neonates (PNs) with gestational age ≤30 weeks and/or birth weight ≤1500 g, in their first 28 days of life. At first transfusion episode, PNs received ABO-Rh(D) matched CB-RBCs if available, or adult RBCs if CB units were not available. At subsequent transfusions, the same regimen was adopted, unless CB-RBCs were unavailable. Overall, 9 patients received CB-RBCs and 11 adult-RBCs; 6 patients (3 in each group) died before ROP assessment. Table 1 illustrates ROP findings in 14 surviving patients. All PNs receiving adult-RBCs developed ROP, while two of six patients in the CB-RBC group did not. Stage 3 ROP was observed in four heavily transfused extremely PNs: three of them were transfused only or mainly with adult-RBCs (patients 8,10 and 14, respectively; Table 1). Transfusions contribute to the overwhelming oxidative burden caused by infections, oxygen therapy and inflammatory diseases in PNs. Unfortunately, to monitor in these patients lipid peroxidation products or other biomarkers of the oxidative stress, requires sophisticated methodologies and exceeding volume of biologic samples. Hence, these investigations are so far confined to the research field. In this regard, the study of Stutchfield et al. suggests that monitoring HbF levels in PNs might be a feasible and reliable tool to figure out to what extent transfusions might favour PAD development