Red cell transfusion thresholds for preterm infants: finally some answers

Effect of days of age at first blood transfusion on intraventricular hemorrhage in very low and extremely low birth weight infants

BACKGROUND

Preterm infants are a group cohort of transfusion recipients due to their low blood volume and underdeveloped hematopoietic system. The objective of this study was to probe the effect of days of age at first blood transfusion on intraventricular hemorrhage (IVH) in very low and extremely low birth weight VLBW and ELBW infants.

RESEARCH DESIGN AND METHODS

Data of 150 VLBW and ELBW infants receiving blood transfusions were reviewed. IVH and non-IVH groups were established. General data on infants and their mothers and data related to blood transfusion, IVH risk factors, and the predictive value of the relevant factors for IVH were analyzed.

RESULTS

The IVH group had lower birth weight, hemoglobin levels on admission, and days of age at first blood transfusion and higher 5-min Apgar score ≤7 points and early transfusion rate. Spontaneous delivery and 5-min Apgar score ≤7 points were risk factors for IVH. Birth weight and days of age at first blood transfusion had predictive value for IVH in VLBW and ELBW infants.

CONCLUSIONS

The younger the days of age at first blood transfusion, the higher the IVH risk. It is necessary to delay the days of age at first blood transfusion and reduce early blood transfusion.

Risk factors associated with anemia of prematurity requiring red blood cell transfusion in very low birth weight infants: a retrospective study

BACKGROUND

Anemia of prematurity (AOP) is prevalent among very low birth weight infants (VLBWIs). Red blood cell (RBC) transfusions, while necessary for managing AOP, have been linked to adverse neonatal outcomes.

METHODS

This retrospective study analyzed the medical records of 98 VLBWIs (24-31 weeks gestation) admitted to the Chungbuk National University Hospital neonatal intensive care unit. Infants were categorized based on RBC transfusion status and birth weight (< 1000 g and 1000-1499 g). Clinical outcomes between the groups were compared.

RESULTS

Of the 98 infants, 35 (35.7%) received RBC transfusions. The RBC transfusion group exhibited significantly higher incidence of bronchopulmonary dysplasia ([Formula: see text]moderate), prolonged invasive mechanical ventilation, intraventricular hemorrhage (grades 1-2), extended time to full enteral feeding, and extended total parenteral nutrition (TPN) compared to the non-RBC transfusion group. Birth weight was inversely correlated with the number of RBC transfusions (p = 0.004). The duration of invasive mechanical ventilation and TPN administration were positively associated with the number of RBC transfusions (p < 0.001 and p = 0.025, respectively).

CONCLUSIONS

The RBC transfusion group experienced more comorbidities than the non-transfusion group. Birth weight, duration of invasive ventilation, and duration of TPN were associated with the number of RBC transfusions. Strategies to reduce the duration of invasive ventilation and early discontinuation of TPN may mitigate the need for RBC transfusions in AOP.

Sex differences in the association of pretransfusion haemoglobin and cognition in preterm infants

OBJECTIVES

To assess sex-specific differences in the association between pre-transfusion haemoglobin values and early neurodevelopmental function.

DESIGN

Observational follow-up of infants with birth weights <1000 g and gestational ages 22-28 weeks who were enrolled in the NICHD Neonatal Research Network Transfusion of Prematures (TOP) Trial at 19 U.S. sites, 2012-2017.

MAIN OUTCOME MEASURES

Pretransfusion haemoglobin values were obtained longitudinally through 36 weeks' postmenstrual age. The infant's mean pretransfusion haemoglobin was used as a marker of degree of anaemia (n=1655 measures). Measures of brain function were obtained at 22-26 months' corrected age using the Bayley Scales of Infant & Toddler Development, third edition (BSID-III) (n=1290 BSID-III scores). Sex-specific estimates for the linear relation between pretransfusion haemoglobin and BSID-III scores were obtained from repeated-measures regression analysis, adjusted for gestational age, birth weight, study site, clinical characteristics, and demographic covariates.

RESULTS

The relation of pretransfusion haemoglobin with 24-month BSID-III scores showed significant, independent interactions with both (1) sex (p=0.046) and (2) retinopathy of prematurity (ROP; p=0.004). In 614 males, BSID-III scores were higher by 1.07 points per g/dL (95% CI 1.58 to 4.33; p=0.008), not differing significantly among the three subscales (cognitive, language and motor; p=0.94). In 247 infants with ROP, BSID-III scores were higher by 2.95 points per g/dL (95% CI 0.28 to 1.87; p<0.0001), uniformly across subscales (p=0.73). These associations were non-significant in 676 females (p=0.96) and 1043 infants without ROP (p=0.81).

CONCLUSIONS

This study demonstrates sex-specific associations between mean pretransfusion haemoglobin (a marker of the severity of anaemia throughout the neonatal intensive care unit [NICU] hospitalisation) and early neurodevelopmental function at 22-26 months' corrected age.

Efficacy of recombinant erythropoietin for the late treatment of anemia of prematurity in a level IV neonatal intensive care unit: a retrospective single-center cohort study

OBJECTIVE

To describe the population to which we administered recombinant erythropoietin and to determine the effectiveness of this treatment as quantified by the change in hematocrit.

STUDY DESIGN

This retrospective chart review study included infants who received erythropoietin for the treatment of anemia of prematurity.

RESULTS

There were 132 infants representing 162 unique treatment courses included in the study. The average duration of therapy was 9 days (±7) and 6 doses (±2). The average change in hematocrit (Hct) was 6.2% (SD 3.9%, p < 0.001). Rise in Hct was associated with a higher number of rEPO doses (p < 0.001) and higher postmenstrual age (p < 0.001). In our small cohort we did not find an association between the number of rEPO doses and retinopathy of prematurity (ROP) requiring treatment.

CONCLUSION

Erythropoietin is safe and effective at treating anemia of prematurity as evidenced by a clinically and statistically significant increase in Hct from baseline.

Packed Red Blood Cell Transfusion as a Predictor of Moderate-Severe Bronchopulmonary Dysplasia: A Comparative Cohort Study of Very Preterm Infants

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is a leading cause of morbidity and mortality in neonatal intensive care units. Our aim was to evaluate association between packed red blood cell transfusion and the development of BPD in very preterm infants.

STUDY DESIGN

This retrospective study of very preterm infants (mean gestational age: 27.1 ± 2.4 weeks, birth weight: 970 ± 271 g) was conducted at Biruni University (Turkey) between July 2016 and December 2020.

RESULTS

BPD developed in 107 of the 246 enrolled neonates, including 47 (43.9%), 27 (25.3%), and 33 (30.8%) diagnosed with mild, moderate, and severe BPD, respectively. A total of 728 transfusions were administered. The increased number (4 transfusions [2-7] vs. 1 [1-3], p = 0.001) and volume of transfusions (75 mL/kg volume [40-130] vs. 20 [15-43], p = 0.001) were significantly higher in infants with BPD compared to those without BPD. The transfusion volume cut-off for the prediction of BPD by receiver operating characteristic curve analysis was 42 mL/kg (sensitivity 73.6%; specificity 75%; area under the receiver-operating characteristic curve: 0.82). In multivariate analysis, multiple transfusions and larger transfusion volume were independent risk factors for moderate-severe BPD.

CONCLUSION

The increased number and volume of transfusions were associated with BPD in very preterm infants. A packed red blood cell transfusion volume ≥42 mL/kg was a statistically significant predictor of the development of BPD at a postmenstrual age of 36 weeks.

KEY POINTS

· Transfusions were found to be an important risk factor for BPD development in very premature infants.. · Number and volume of transfusion were associated with the severity of BPD.. · Optimal cut point volume of transfusion for prediction of BPD was 42 mL/kg body weight..

Timing of Red Blood Cell Transfusions and Occurrence of Necrotizing Enterocolitis: A Secondary Analysis of a Randomized Clinical Trial

Importance

Observational studies often report that anemia and red blood cell (RBC) transfusions are associated with a higher risk of necrotizing enterocolitis (NEC) among extremely low-birthweight (ELBW) infants.

Objective

To evaluate whether there is a temporal association between 72-hour hazard periods of exposure to RBC transfusions and NEC among ELBW infants randomized to either higher or lower hemoglobin transfusion thresholds.

Design, Setting, and Participants

This post hoc secondary analysis of 1690 ELBW infants who survived to postnatal day 10 enrolled in the Transfusion of Prematures (TOP) randomized multicenter trial between December 1, 2012, and April 12, 2017, was performed between June 2021 and July 2023.

Exposures

First, the distribution of RBC transfusions and the occurrence of NEC up to postnatal day 60 were examined. Second, 72-hour posttransfusion periods were categorized as hazard periods and the pretransfusion periods of variable duration as control periods. Then, the risk of NEC in posttransfusion hazard periods was compared with that in pretransfusion control periods, stratifying the risk based on randomization group (higher or lower hemoglobin transfusion threshold group).

Main Outcomes and Measures

The primary outcome was incidence of NEC stage 2 or 3. Secondary outcomes included the incidence rates of NEC within five 10-day intervals, taking into account the number of days at risk.

Results

Of 1824 ELBW infants randomized during the TOP trial, 1690 were included in the present analysis (mean [SD] gestational age, 26.0 [1.5] weeks; 899 infants [53.2%] were female). After categorizing 4947 hazard periods and 5813 control periods, we identified 133 NEC cases. Fifty-nine of these cases (44.4%) occurred during hazard periods. Baseline and clinical characteristics of infants with NEC during hazard periods did not differ from those of infants with NEC during control periods. The risk of NEC was 11.9 per 1000 posttransfusion hazard periods and 12.7 per 1000 control periods (adjusted risk ratio, 0.95; 95% CI, 0.68-1.32; P = .74). This risk did not differ significantly between randomization groups, but the incidence rate of NEC per 1000 days peaked between postnatal days 20 and 29 in the lower hemoglobin transfusion threshold group.

Conclusions and Relevance

The findings of this post hoc analysis suggest that, among ELBW infants with the hemoglobin ranges occurring in the TOP trial, exposure to RBC transfusions was not temporally associated with a higher risk of NEC during 72-hour posttransfusion hazard periods. Given that the incidence rate of NEC peaked between postnatal days 20 and 29 among infants with lower hemoglobin values, a more in-depth examination of this at-risk period using larger data sets is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT01702805.

Blood Donor Sex and Outcomes in Transfused Infants

Red blood cell transfusion is common in neonatal intensive care. Multiple trials have evaluated different thresholds for when to administer red blood cell transfusion. In contrast, there has been less focus on studies of the characteristics of red blood cells transfused into neonates. In this review, the authors summarize the emerging literature on the potential impact of the sex of blood donors on outcomes in transfused neonates using a systematic search strategy. The authors review the uncertainty generated from studies with conflicting findings and discuss considerations regarding the impact of blood donor sex and other characteristics on neonatal outcomes.

Patient Blood Management in Neonates

Patient blood management (PBM) is an evidence-based care package to improve patient outcomes by optimizing a patient's blood, minimizing blood loss, and the effective management and, when appropriate, the tolerance of anemia. It is relatively well-developed in adult medicine and remains in its infancy in neonatology. This review explores why evidence-based guidelines are insufficient, discusses the variations in neonatal transfusion practice and why this matters, and provides the key updates in neonatal transfusion practice. The authors give examples of a successful neonatal PBM program and single-center projects.

Near-Infrared Spectroscopy to Guide and Understand Effects of Red Blood Cell Transfusion

This review is a summary of available evidence regarding the use of near-infrared spectroscopy (NIRS) to help better guide and understand the effects of red blood cell (RBC) transfusion in neonatal patients. We review recent literature demonstrating the changes that take place in regional tissue oxygen saturation (rSO2) resulting from RBC transfusion. We also discuss in detail if any correlation exists between rSO2 and hemoglobin values in neonates. Finally, we review studies that have evaluated the use of NIRS as a transfusion guide during neonatal intensive care.

[Interpretation of the key updates in the 2022 European guideline on the management of neonatal respiratory distress syndrome]

With the deepening of clinical research, the management of neonatal respiratory distress syndrome (RDS) needs to be optimized and improved. This article aims to introduce the 2022 European guideline on the management of neonatal RDS, focusing on its key updates. The guide has optimized the management of risk prediction for preterm birth, maternal referral, application of prenatal corticosteroids, application of lung protective ventilation strategies, and general care for infants with RDS. The guideline is mainly applicable to the management of RDS in neonates with gestational age greater than 24 weeks.

Red Blood Cell Transfusion Thresholds for Anemia of Prematurity

Anemia of prematurity affects the majority of preterm infants, particularly extremely low birthweight infants. Anemia of prematurity arises from both innate and iatrogenic causes and results in more than 80% of extremely preterm infants receiving red blood cell transfusions during the first month after birth. Multiple randomized controlled trials were conducted to evaluate the effect of using lower versus higher transfusion thresholds based on hemoglobin levels. These trials showed no difference in the primary outcome of neurodevelopmental impairment at 2 years of age between lower and higher thresholds. However, some uncertainties about transfusion thresholds remain. This review elaborates the following: 1) the etiology, prevention, and treatment of anemia of prematurity with a focus on red blood cell transfusions, 2) the history of randomized controlled trials on the treatment of anemia of prematurity, and 3) limitations of the evidence and remaining questions about thresholds for red blood cell transfusions in preterm infants.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome: 2022 Update

Respiratory distress syndrome (RDS) care pathways evolve slowly as new evidence emerges. We report the sixth version of "European Guidelines for the Management of RDS" by a panel of experienced European neonatologists and an expert perinatal obstetrician based on available literature up to end of 2022. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, appropriate maternal transfer to a perinatal centre, and appropriate and timely use of antenatal steroids. Evidence-based lung-protective management includes initiation of non-invasive respiratory support from birth, judicious use of oxygen, early surfactant administration, caffeine therapy, and avoidance of intubation and mechanical ventilation where possible. Methods of ongoing non-invasive respiratory support have been further refined and may help reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation by targeted use of postnatal corticosteroids remains essential. The general care of infants with RDS is also reviewed, including emphasis on appropriate cardiovascular support and judicious use of antibiotics as being important determinants of best outcome. We would like to dedicate this guideline to the memory of Professor Henry Halliday who died on November 12, 2022.These updated guidelines contain evidence from recent Cochrane reviews and medical literature since 2019. Strength of evidence supporting recommendations has been evaluated using the GRADE system. There are changes to some of the previous recommendations as well as some changes to the strength of evidence supporting recommendations that have not changed. This guideline has been endorsed by the European Society for Paediatric Research (ESPR) and the Union of European Neonatal and Perinatal Societies (UENPS).

Impact of Early Hemoglobin Levels on Neurodevelopment Outcomes of Two-Year-Olds in Very Preterm Children

OBJECTIVE

To evaluate, in very preterm infants, the hemoglobin (Hb) levels during the first 24 h and the neurodevelopment outcomes at 24 months of corrected age.

DESIGN, SETTING, AND PATIENTS

We conducted a secondary analysis of the French national prospective and population-based cohort EPIPAGE-2. The eligible study participants were live-born singletons who were born before 32 weeks of gestational age, with early Hb levels who were admitted to the neonatal intensive care unit.

MAIN OUTCOME MEASURES

The early Hb levels for an outcome survival at 24 months of corrected age without neurodevelopmental impairment were measured. The secondary outcomes were survival at discharge and without severe neonatal morbidity.

RESULTS

Of the 2158 singletons of <32 weeks with mean early Hb levels of 15.4 (±2.4) g/dL, 1490 of the infants (69%) had a follow-up at two years of age. An early Hb of 15.2 g/dL is the minimum receiving operating characteristic curve at the 24 months risk-free level, but the area under the curve at 0.54 (close to 50%) indicates that this rate was not informative. In logistic regression, no association was found between early Hb levels and outcomes at two years of age (aOR 0.966; 95% CI [0.775-1.204]; p = 0.758) but rather there was a correlation found with severe morbidity (aOR 1.322; 95% CI [1.003-1.743]; p = 0.048). A risk stratification tree showed that male newborns of >26 weeks with Hb of <15.5 g/dL (n = 703) were associated with a poor outcome at 24 months (OR 1.9; CI: [1.5-2.4] p < 0.01).

CONCLUSIONS

Early low Hb levels are associated with major neonatal morbidities in VP singletons, but not with neurodevelopment outcomes at two years of age, except in male infants of >26 Weeks GA.

Sex Differences in the Association of Pretransfusion Hemoglobin Levels with Brain Structure and Function in the Preterm Infant

OBJECTIVE

To assess sex-specific differences in early brain structure and function of preterm infants after red blood cell (RBC) transfusions.

STUDY DESIGN

A single-center subset of infants with a birth weight <1000 g and gestational age 22-29 weeks were enrolled from the National Institute of Child Health and Human Development's Neonatal Research Network Transfusion of Prematures Trial. Hemoglobin (Hb) concentration obtained directly before each transfusion (pretransfusion Hb [ptHb]) was obtained longitudinally throughout each infant's neonatal intensive care unit stay and used as a marker of degree of anemia (n = 97). Measures of regional brain volumes using magnetic resonance imaging were obtained at ∼40 weeks postmenstrual age or at hospital discharge, if earlier (n = 29). Measures of brain function were obtained at 12 months corrected age using the Bayley Scales of Infant & Toddler Development, 3rd Edition (n = 34).

RESULTS

PtHb was positively correlated with neonatal cerebral white matter volume in males (B = +0.283; P = .006), but not females (B = -0.099; P = .713), resulting in a significant sex interaction (P = .010). Bayley-III gross motor scores and a pooled mean score were significantly lower in association with higher ptHb in females (gross motor score: B = -3.758; P = .013; pooled mean score: B = -1.225; P = .030), but not males (gross motor score: B = +1.758; P = .167; pooled mean score: B = +0.621; P = .359). Higher ptHb was associated with descriptively lower performance on multiple Bayley-III subscales in females, but not in males.

CONCLUSIONS

This study demonstrates sex-specific associations between an early marker of anemia and RBC transfusion status (ie, ptHb) with both neonatal white matter volume and early cognitive function at age 12 months in preterm infants.

Patterns and Determinants of Blood and Blood Products Transfusion in Neonate: An Experience of Single Institute

BACKGROUND: Neonates requiring intensive care are among the most frequently transfused group of patients. Indications for blood transfusion in neonates could be physiological or pathological. However, despite frequent blood transfusions in neonates in Iraq, there is a paucity of studies on its indications and patterns among neonates in our setting. AIM: The aim of the study is to shed light on the details of giving blood and blood products in the unit of neonate in Children Welfare Teaching hospital, Baghdad and the justifications for giving and its complication. PATIENTS AND METHODS: A descriptive study (cross-section study) includes all neonates admitted to neonatal care unit in Children Welfare Teaching Hospital. The study includes a group of newborns who were blood transfused during their admission to hospital, over a period of 6 months from October 1, 2019 to March 30, 2020. All data were collected from each patient and recorded in predesigned forma, these data include patient’s clinical data and analyzed using descriptive statistics. RESULTS: A total number of cases admitted over a period of 6 months were 862. One hundred and forty neonates received blood and its products transfusion, (61.4%) were male and (38.6%) were female, (62.9%) received packed red blood cells (PRBCs) followed by (18.6%) received exchange transfusion, (11.4%) received Fresh frozen plasma and (7.1%) received platelets. Most neonates received blood products transfused at (3–4) weeks. Post-natal age and were term babies (37–41) weeks. Gestational age mostly received PRBCs. CONCLUSIONS: Most neonates with a high rate of blood and blood product transfusion were males, term, need assistant ventilation, and transfused at 3–4 weeks postnatal age.

Thresholds for blood transfusion in extremely preterm infants: A review of the latest evidence from two large clinical trials

There are two recently completed large randomized clinical trials of blood transfusions in the preterm infants most at risk of requiring them. Liberal and restrictive strategies were compared with composite primary outcome measures of death and neurodevelopmental impairment. Infants managed under restrictive guidelines fared no worse in regard to mortality and neurodevelopment in early life. The studies had remarkably similar demographics and used similar transfusion guidelines. In both, there were fewer transfusions in the restrictive arm. Nevertheless, there were large differences between the studies in regard to transfusion exposure with almost 3 times the number of transfusions per participant in the transfusion of prematures (TOP) study. Associated with this, there were differences between the studies in various outcomes. For example, the combined primary outcome of death or neurodevelopmental impairment was more likely to occur in the TOP study and the mortality rate itself was considerably higher. Whilst the reasons for these differences are likely multifactorial, it does raise the question as to whether they could be related to the transfusions themselves? Clearly, every effort should be made to reduce exposure to transfusions and this was more successful in the Effects of Transfusion Thresholds on Neurocognitive Outcomes (ETTNO) study. In this review, we look at factors which may explain these transfusion differences and the differences in outcomes, in particular neurodevelopment at age 2 years. In choosing which guidelines to follow, centers using liberal guidelines should be encouraged to adopt more restrictive ones. However, should centers with more restrictive guidelines change to ones similar to those in the studies? The evidence for this is less compelling, particularly given the wide range of transfusion exposure between studies. Individual centers already using restrictive guidelines should assess the validity of the findings in light of their own transfusion experience. In addition, it should be remembered that the study guidelines were pragmatic and acceptable to a large number of centers. The major focus in these guidelines was on hemoglobin levels which do not necessarily reflect tissue oxygenation. Other factors such as the level of erythropoiesis should also be taken into account before deciding whether to transfuse.