Low fraction of fetal haemoglobin is associated with retinopathy of prematurity in the very preterm infant

Abstract

BackgroundBlood loss and adult blood transfusions are common during the neonatal period in preterm infants. The objective of the study was to clarify if degree of loss of fetal haemoglobin (HbF) was associated with later retinopathy of prematurity (ROP).MethodsRetrospective observational cohort study. In total, 452 infants born <30 gestational weeks at a tertiary level neonatal intensive care unit in Sweden in 2009–2015 were included, 385 of whom had final ROP outcome. Mean fractions of HbF (%) during the first postnatal week were calculated from 11 861 arterial blood gas analyses. The relationship between fractions of HbF (%) and ROP was evaluated.ResultsThe mean (SD) gestational age (GA) at birth was 26.4 (1.8) weeks. In total, 104 (27 %) infants developed ROP. Higher fraction of HbF (%) was associated with a lower prevalence of ROP, OR by a 10% increase 0.83 (95% CI: 0.71 to 0.97; p=0.019), following adjustment for GA at birth, small for GA and sex. Infants with HbF (%) in the lowest quartile had OR of 22.0 (95% CI: 8.1 to 59.2; p<0.001) for ROP development compared with those in the highest quartile. The predictive ability (area under the curve) of HbF (%) in the full model during the first week was 0.849 for ROP.ConclusionsEarly low fraction of HbF is independently associated with abnormal retinal neurovascular development in the very preterm infant. The potential benefit of minimising blood loss on development of ROP will be investigated in a multicenter randomised trial (NCT04239690).

Transfusion-Free Survival Predicts Severe Retinopathy in Preterm Neonates

“…The authors found that in comparison with neonates without ROP, the 104 neonates developing any stage of ROP had equivalent HbF at birth but lower HbF levels in the first postnatal week. The probability for developing any ROP was about 60% in neonates with a mean HbF value of 40% in the first week of life, compared with only a 10% probability in those with a mean HbF value of 90% ( 31 ). Considering that the GA of enrolled patients was 26.4 ± 1.7 weeks, these findings strongly suggest that low-HbF-related causal mechanisms of ROP operate at a PMA lower than 31 weeks, in contrast to what Lust et al suggested ( 27 ).…”

“…The association between repeated transfusions and ROP is supported by robust scientific evidence ( 7 – 9 , 16 , 25 – 28 ). The risk for developing ROP seems to be higher if RBC transfusions are administered at an early period of life ( 27 , 29 – 31 ). In this regard, the findings emerging in the present study highlight two main points.…”

“…However, only three neonates with severe ROP were included in this study; no information related to transfusions was provided. Finally, Hellström et al retrospectively evaluated HbF data collected at birth and in the first seven postnatal days in 385 infants ( 31 ). The authors found that in comparison with neonates without ROP, the 104 neonates developing any stage of ROP had equivalent HbF at birth but lower HbF levels in the first postnatal week.…”

BORN study: a multicenter randomized trial investigating cord blood RBC transfusions to reduce the ROP severity in extremely low gestational age neonates.

“…23 Hellström et al (retrospectively study including 385 infants born at GA ≤ 30 weeks) found that neonates developing any stage of ROP had equivalent HbF at birth but lower HbF levels in the rst postnatal week. 24 The probability of ROP was about 60% in neonates with a mean HbF value of 40%, compared to only 10% probability in those with a mean HbF value of 90%. 24 RBC transfusions represent the mainstay for treating prematurity anemia and are unavoidable for most patients.…”

Morphology and biological data in cord blood eryhtrocyte units resembles adult units after processing and storage – Meets current quality recommendations

“…Therefore, using UCB for transfusions instead of blood from adult donors could be an alternative to reduce anemia and the risk for hyperoxemia and fluctuating oxygenation which are prominent risk factors for neonatal morbidities. In accordance, frequent diagnostic blood sampling in combination with blood transfusions in very preterm infants has been associated with an increased risk for neonatal morbidities such as bronchopulmonary dysplasia (BPD) and rethinopathy of prematurity (ROP) [21,22]. ROP is a leading cause of childhood blindness worldwide; 1.2 percent of premature infants (year 2010) developed ROP [23,24].…”