Transfusion-related acute gut injury: necrotizing enterocolitis in very low birth weight neonates after packed red blood cell transfusion

Bridging the evidence-to-practice gap: Advancing neonatal blood transfusion. A narrative review of recent guidelines

Neonates represent a distinct population within the context of transfusion medicine. Blood transfusions in neonates are vital interventions for multiple conditions, despite their inherent risks and potential complications. Differences in physiology and other transfusion risk factors unique to this group require careful adaptation of transfusion guidelines. This article seeks to offer a thorough overview of the current evidence-based practices for RBC administration in neonates. It covers the collection, processing and storage of RBCs and discusses the research underpinning the most recent transfusion guidelines. Furthermore, it emphasizes the challenges in establishing precise cut-off values for these conditions in both preterm and critically ill neonates and discusses indications for transfusion, thresholds, current guidelines, and potential complications. Finally, it highlights gaps in critical areas of transfusion related research and proposes future targets for research.

Spatial transcriptomics delineates potential differences in intestinal phenotypes of cardiac and classical necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a devastating neonatal gastrointestinal disease, often resulting in multi-organ failure and death. While classical NEC is strictly associated with prematurity, cardiac NEC is a subset of the disease occurring in infants with comorbid congenital heart disease. Despite similar symptomatology, the NEC subtypes vary slightly in presentation and may represent etiologically distinct diseases. We compared ileal spatial transcriptomes of patients with cardiac and classical NEC. Epithelial and immune cells cluster well by cell-type segment and NEC subtype. Differences in metabolism and immune cell activation functionally differentiate the cell-type makeup of the NEC subtypes. The classical NEC phenotype is defined by dysbiosis-induced inflammatory signaling and metabolic acidosis, while that of cardiac NEC involves reduced angiogenesis and endoplasmic reticulum stress-induced apoptosis. Despite subtype-associated clinical and demographic variability, spatial transcriptomics has substantiated pathway and network differences within immune and epithelial segments between cardiac and classical NEC.

Diagnostic and Prognostic Value of Hematological Parameters in Necrotizing Enterocolitis: A Systematic Review

Background/Objectives: Necrotizing enterocolitis (NEC) is a severe, potentially fatal gastrointestinal disease that primarily affects preterm neonates, especially those with very low birth weight (<1500 g). Despite extensive research, its pathophysiology remains unclear, with NEC considered a spectrum of disorders driven by systemic inflammation, microbiota dysregulation, and intestinal hypoxic injury. Diagnosis is challenging due to its subtle presentation and reliance on clinical and radiographic findings, underscoring the urgent need for reliable early biomarkers. Complete blood count (CBC) is one of the most frequently performed laboratory tests in neonatal care, providing valuable insights associated with hematologic alterations associated with NEC. Given its cost-effectiveness, accessibility, and rapid turnaround time, CBC parameters have been increasingly investigated for their diagnostic and prognostic potential in NEC. This systematic review consolidates existing evidence on the diagnostic and prognostic utility of CBC parameters in NEC, examining their association with disease onset, progression, and outcomes. Methods: A systematic review of the literature in PubMed and Scopus databases was conducted, between February 25 and December 2024. Results: Following a PRISMA-compliant search strategy, 77 eligible studies were included, analyzing data from 295,195 neonates, of whom 14,570 had NEC. Among the 77 studies, 17 examined NEC-associated mortality as a primary outcome, while 13 studies focused on the development of predictive models incorporating CBC parameters alongside other clinical and laboratory data to assess NEC severity and prognosis in neonates. The findings highlight the potential of CBC-derived markers to facilitate early NEC detection and risk stratification. However, variations in study design and diagnostic criteria highlight the need for prospective studies to validate their clinical use. Conclusions: Despite advancements in understanding NEC, its diagnosis remains challenging due to the absence of fully reliable biomarkers. CBC parameters show promise in offering early diagnostic and prognostic insights. However, further validation is needed for their routine integration into NICU practice. Given the persistent challenges in NEC diagnosis and management, our findings highlight the necessity for integrated scoring systems that combine hematologic, clinical, and radiologic data to enhance early detection and optimize neonatal care. Further research is essential to refine these predictive models, enabling timely interventions and improving survival rates in NEC-affected neonates.

Severe anemia predisposes very premature infants to transfusion-associated necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a catastrophic inflammatory bowel necrosis of premature infants. The etiology is unknown, but 25-40 % of cases have a history of red blood cell (RBC) transfusions in the preceding 48 h. This association has been noted in retrospective case/case-control studies, and many meta-analyses, and in a murine model. However, we still need human studies with larger, adequately powered cohorts to confirm this association and determine the operant mechanisms. The murine model shows that severe anemia leads to macrophage infiltration in the gut mucosa. Subsequent RBC transfusions containing free hemoglobin, activate nuclear factor-kappa B-mediated inflammatory changes and cause NEC-like mucosal injury. This review summarizes current human and experimental data to evaluate ta-NEC and hitherto unanswered mechanistic questions. If a causal relationship between transfusions and NEC is proven, these data could help develop effective therapeutic strategies.

Red Blood Cell Transfusion in European Neonatal Intensive Care Units, 2022 to 2023

Importance

Red blood cell (RBC) transfusions are frequently administered to preterm infants born before 32 weeks of gestation in the neonatal intensive care unit (NICU). Two randomized clinical trials (Effects of Transfusion Thresholds on Neurocognitive Outcomes of Extremely Low-Birth-Weight Infants [ETTNO] and Transfusion of Prematures [TOP]) found that liberal RBC transfusion thresholds are nonsuperior to restrictive thresholds, but the extent to which these results have been integrated into clinical practice since publication in 2020 is unknown.

Objective

To describe neonatal RBC transfusion practice in Europe.

Design, Setting, and Participants

This international prospective observational cohort study collected data between September 1, 2022, and August 31, 2023, with a 6-week observation period per center, from 64 NICUs in 22 European countries. Participants included 1143 preterm infants born before 32 weeks of gestation.

Exposure

Admission to the NICU.

Main Outcomes and Measures

Study outcome measures included RBC transfusion prevalence rates, cumulative incidence, indications, pretransfusion hemoglobin (Hb) levels, volumes, and transfusion rates, Hb increment, and adverse effects of RBC transfusion.

Results

A total of 1143 preterm infants were included (641 male [56.1%]; median gestational age at birth, 28 weeks plus 2 days [IQR, 26 weeks plus 2 days to 30 weeks plus 2 days]; median birth weight, 1030 [IQR, 780-1350] g), of whom 396 received 1 or more RBC transfusions, totaling 903 transfusions. Overall RBC transfusion prevalence rate during postnatal days 1 to 28 was 3.4 transfusion days per 100 admission days, with considerable variation across countries, only partly explained by patient mix. By day 28, 36.5% (95% CI, 31.6%-41.5%) of infants had received at least 1 transfusion. Most transfusions were given based on a defined Hb threshold (748 [82.8%]). Hemoglobin levels before transfusions indicated for threshold were below the restrictive thresholds set by ETTNO in 324 of 729 transfusions (44.4%) and TOP in 265 of 729 (36.4%). Conversely, they were between restrictive and liberal thresholds in 352 (48.3%) and 409 (56.1%) transfusions, respectively, and above liberal thresholds in 53 (7.3%) and 55 (7.5%) transfusions, respectively. Most transfusions given based on threshold had volumes of 15 mL/kg (470 of 738 [63.7%]) and were administered over 3 hours (400 of 738 [54.2%]), but there was substantial variation in dose and duration.

Conclusions and Relevance

In this cohort study of very preterm infants, most transfusions indicated for threshold were given for pretransfusion Hb levels above restrictive transfusion thresholds evaluated in recent trials. These results underline the need to optimize practices and for implementation research to support uptake of evidence.

Near-infrared spectroscopy for perioperative assessment and neonatal interventions

Perioperative applications of near-infrared spectroscopy (NIRS) to monitor regional tissue oxygenation and perfusion in cardiac and noncardiac surgery are of increasing interest in neonatal care. Complex neonatal surgery can impair adequate oxygen delivery and tissue oxygen consumption and increase the risk of neurodevelopmental delay. Coupled with conventional techniques, NIRS monitoring may enable targeted hemodynamic management of the circulation in both cardiac and noncardiac surgical procedures. In this narrative review, we discuss the application of perioperative NIRS in specific neonatal interventions, including surgical intervention for congenital heart defects, definitive closure of the patent ductus arteriosus, neurological and gastrointestinal disorders, and use of extracorporeal membrane oxygenation. We identified areas for future research within disease-specific indications and offer a roadmap to aid in developing evidence-based targeted diagnostic and management strategies in neonates. IMPACT: There is growing recognition that perioperative NIRS monitoring, used in conjunction with conventional monitoring, may provide critical hemodynamic information that either complements clinical impressions or delivers novel physiologic insight into the neonatal circulatory and perfusion pathways.

Effects of the feeding protocol during blood transfusion on splanchnic tissue oxygenation and complications in very premature infants

Background

The effects of blood transfusions on splanchnic oxygenation and complications related to blood transfusions, including red blood cell (RBC) transfusions, in premature infants undergoing enteral feeding, to provide clinical evidence for a management protocol for premature infants during the peri-transfusion period.

Methods

This single-blind, randomized, controlled trial enrolled sixty eligible preterm infants who were randomly divided into the withholding feeding group (n = 30) or feeding group (n = 30). Enteral feeding was withheld for 8 h, beginning from the start of transfusion infants in the feeding group were fed according to the pre-transfusion feeding approach during and after RBC transfusion.

Results

Baseline characteristics of those in the withholding and feeding groups were as follows: gestational age (weeks) 27.52 (24.86-30.14) and 27.13 (25.43-30.14); birth weight (g), 1,027 (620-1,450) and 1,027 (620-1,270); blood transfusion day, 48 (14-79) and 39 (10-78); and hemoglobin before blood transfusion (g/L), 81.67 (±10.56) and 85.93 (±14.77). No significant differences were observed between groups at baseline. No significant differences were observed in the average splanchnic tissue oxygenation changes or clinical results at any time. One patient in the withholding feeding group experienced transfusion-associated necrotizing enterocolitis.

Conclusions

No differences in splanchnic oxygenation observed these feeding protocols. This study suggests the feasibility of a sizable trial to evaluate clinical outcomes. The risks of mesenteric ischemia and transfusion-related necrotizing enterocolitis for premature infants were not increased by enteral feeding during RBC transfusion.

Clinical trial registration

ChiCTR2200055726 (https://www.chictr.org.cn/).

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.

Clinical Dilemma Involving Treatments for Very Low-Birth-Weight Infants and the Potential Risk of Necrotizing Enterocolitis: A Narrative Literature Review

Necrotizing enterocolitis (NEC) is a critical gastrointestinal emergency with substantial morbidity and mortality risks, especially for very low-birth-weight (VLBW) infants, and unclear multifactorial pathophysiology. Whether common treatments for VLBW infants increase the NEC risk remains controversial. Indomethacin (utilized for patent ductus arteriosus) offers benefits but is concerning because of its vasoconstrictive impact on NEC susceptibility. Similarly, corticosteroids used to treat bronchopulmonary dysplasia may increase vulnerability to NEC by compromising immunity and altering the mesenteric blood flow. Histamine-2 receptor blockers (used to treat gastric bleeding) may inadvertently promote NEC by affecting bacterial colonization and translocation. Doxapram (used to treat apnea) poses a risk of gastrointestinal disturbance via gastric acid hypersecretion and circulatory changes. Glycerin enemas aid meconium evacuation but disrupt microbial equilibrium and trigger stress-related effects associated with the NEC risk. Prolonged antibiotic use may unintentionally increase the NEC risk. Blood transfusions for anemia can promote NEC via interactions between the immune response and ischemia-reperfusion injury. Probiotics for NEC prevention are associated with concerns regarding sepsis and bacteremia. Amid conflicting evidence, this review unveils NEC risk factors related to treatments for VLBW infants, offers a comprehensive overview of the current research, and guides personalized management strategies, thereby elucidating this clinical dilemma.

Study protocol of the WashT Trial: transfusion with washed versus unwashed red blood cells to reduce morbidity and mortality in infants born less than 28 weeks' gestation - a multicentre, blinded, parallel group, randomised controlled trial

INTRODUCTION

Many extremely preterm newborns develop anaemia requiring a transfusion, with most receiving three to five transfusions during their admission. While transfusions save lives, the potential for transfusion-related adverse outcomes is an area of growing concern. Transfusion is an independent predictor of death and is associated with increased morbidity, length of hospital stay, risk of infection and immune modulation. The underlying mechanisms include adverse pro-inflammatory and immunosuppressive responses. Evidence supports an association between transfusion of washed red cells and fewer post-transfusion complications potentially through removal of chemokines, lipids, microaggregates and other biological response modifiers. However, the clinical and cost-effectiveness of washed cells have not been determined.

METHODS AND ANALYSIS

This is a multicentre, randomised, double-blinded trial of washed versus unwashed red cells. Infants <28 weeks' gestation requiring a transfusion will be enrolled. Transfusion approaches will be standardised within each study centre and will occur as soon as possible with a recommended fixed transfusion volume of 15 mL/kg whenever the haemoglobin is equal to or falls below a predefined restrictive threshold, or when clinically indicated. The primary outcome is a composite of mortality and/or major morbidity to first discharge home, defined as one or more of the following: physiologically defined bronchopulmonary dysplasia; unilateral or bilateral retinopathy of prematurity grade >2, and; necrotising enterocolitis stage ≥2. To detect a 10% absolute reduction in the composite outcome from 69% with unwashed red blood cell (RBCs) to 59% with washed RBCs with 90% power, requires a sample size of 1124 infants (562 per group). Analyses will be performed on an intention-to-treat basis with a prespecified statistical analysis plan. A cost-effectiveness analysis will also be undertaken.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Women's and Children's Health Network Human Research Ethics Committee (HREC/12/WCHN/55). The study findings will be disseminated through peer-reviewed articles and conferences.

TRIAL REGISTRATION NUMBER

ACTRN12613000237785 Australian New Zealand Clinical Trials Registry.

Development of necrotizing enterocolitis after blood transfusion in very premature neonates

BACKGROUND

Prior studies report conflicting evidence on the association between packed red blood cell (PRBC) transfusions and necrotizing enterocolitis (NEC), especially in early weeks of life where transfusions are frequent and spontaneous intestinal perforation can mimic NEC. The primary objective of this study was to evaluate the association between PRBC transfusions and NEC after day of life (DOL) 14 in very premature neonates.

METHODS

A retrospective cohort analysis of very premature neonates was conducted to investigate association between PRBC transfusions and NEC after DOL 14. Primary endpoints were PRBC transfusions after DOL 14 until the date of NEC diagnosis, discharge, or death. Wilcoxon ranked-sum and Fisher's exact tests, Cox proportional hazards regression, and Kaplan-Meier curves were used to analyze data.

RESULTS

Of 549 premature neonates, 186 (34%) received transfusions after DOL 14 and nine (2%) developed NEC (median DOL = 38; interquartile range = 32-46). Of the nine with NEC after DOL 14, all were previously transfused (P < 0.001); therefore, hazard of NEC could not be estimated. Post hoc analysis of patients from DOL 10 onward included five additional patients who developed NEC between DOL 10 and DOL 14, and the hazard of NEC increased by a factor of nearly six after PRBC transfusion (hazard ratio = 5.76, 95% confidence interval = 1.02-32.7; P = 0.048).

CONCLUSIONS

Transfusions were strongly associated with NEC after DOL 14. Prospective studies are needed to determine if restrictive transfusion practices can decrease incidence of NEC after DOL 14.

Machine learning-based risk factor analysis of necrotizing enterocolitis in very low birth weight infants

This study used machine learning and a national prospective cohort registry database to analyze the major risk factors of necrotizing enterocolitis (NEC) in very low birth weight (VLBW) infants, including environmental factors. The data consisted of 10,353 VLBW infants from the Korean Neonatal Network database from January 2013 to December 2017. The dependent variable was NEC. Seventy-four predictors, including ambient temperature and particulate matter, were included. An artificial neural network, decision tree, logistic regression, naïve Bayes, random forest, and support vector machine were used to evaluate the major predictors of NEC. Among the six prediction models, logistic regression and random forest had the best performance (accuracy: 0.93 and 0.93, area under the receiver-operating-characteristic curve: 0.73 and 0.72, respectively). According to random forest variable importance, major predictors of NEC were birth weight, birth weight Z-score, maternal age, gestational age, average birth year temperature, birth year, minimum birth year temperature, maximum birth year temperature, sepsis, and male sex. To the best of our knowledge, the performance of random forest in this study was among the highest in this line of research. NEC is strongly associated with ambient birth year temperature, as well as maternal and neonatal predictors.

Association between prognostic factors and the clinical deterioration of preterm neonates with necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is responsible for most morbidity and mortality in neonates. Early recognition of the clinical deterioration in newborns with NEC is essential to enhance the referral and management and potentially improve the outcomes. Here, we aimed to identify the prognostic factors and associate them with the clinical deterioration of preterm neonates with NEC. We analyzed the medical records of neonates with NEC admitted to our hospital from 2016 to 2021. We ascertained 214 neonates with NEC. The area under the receiver operating characteristic (ROC) curve and cut-off level of age at onset, C-reactive protein (CRP), leukocyte count, and platelet count for the clinical deterioration of preterm neonates with NEC was 0.644 and 10.5 days old, 0.694 and 4.5 mg/L, 0.513 and 12,200/mm³, and 0.418 and 79,500/mm³, respectively. Late-onset, history of blood transfusion, thrombocytopenia, and elevated CRP were significantly associated with the clinical deterioration of neonates with NEC (p =  < 0.001, 0.017, 0.001, and < 0.001, respectively), while leukocytosis, gestational age, and birth weight were not (p = 0.073, 0.274, and 0.637, respectively). Multivariate analysis revealed that late-onset and elevated CRP were strongly associated with the clinical deterioration of neonates with NEC, with an odds ratio of 3.25 (95% CI = 1.49-7.09; p = 0.003) and 3.53 (95% CI = 1.57-7.95; p = 0.002), respectively. We reveal that late-onset and elevated CRP are the independent prognostic factor for the clinical deterioration of preterm neonates with NEC. Our findings suggest that we should closely monitor preterm neonates with NEC, particularly those with late-onset of the disease and those with an elevated CRP, to prevent further clinical deterioration and intervene earlier if necessary.

Packed red blood cell transfusion in preterm infants

Premature infants commonly receive adult packed red blood cells (pRBCs) during their hospital stay. As adult erythrocytes differ substantially from those of preterm infants, transfusion of adult pRBCs into preterm infants can be considered inappropriate for the physiology of a preterm infant. An absence of standardisation of transfusion protocols makes it difficult to compare and interpret pertinent clinical data, as reflected by unclear associations between pRBC transfusion and complications related to prematurity, such as bronchopulmonary dysplasia, neurodevelopmental impairment, retinopathy of prematurity, or necrotising enterocolitis. The difficulty in interpreting clinical data is further increased by differences in study designs that either overestimate pRBC-associated complications of prematurity or have not yet been designed to directly link pRBC transfusions to their respective complications. Thus, neonatal transfusion practice has become an ongoing difficulty, in which differences in transfusion guidelines hinder the ability to generate comparable clinical data, and heterogeneity in clinical data prevents the implementation of standardised transfusion protocols. To overcome these issues, novel approaches with biochemical-clinical translational designs could enable clinicians to gather causal evidence instead of circumstantial correlation.

Effects of Taro (Colocasia esculenta) Water-Soluble Non-Starch Polysaccharide, Lactobacillus acidophilus, Bifidobacterium breve, Bifidobacterium infantis, and Their Synbiotic Mixtures on Pro-Inflammatory Cytokine Interleukin-8 Production

In the past decades, the regulation of pro-inflammatory cytokine production, including interleukin-8 (IL-8), has been the goal of many targeted therapeutic interventions for Necrotising enterocolitis (NEC), a gastrointestinal disease commonly associated with a very low birth weight in preterm infants. In this study, the ability to regulate the production of IL-8 of the water-soluble non-starch polysaccharide (WS-NSP) from taro corm (Tc-WS-NSP) extracted using a conventional (CE) or improved conventional (ICE) extraction method, of the probiotics Lactobacillus acidophilus, Bifidobacterium breve, and Bifidobacterium infantis, and their synbiotic mixtures were evaluated. The TNF-α stimulated HT-29 cells were incubated with undigested or digested Tc-WS-NSPs (CE or ICE), probiotics, and their synbiotic mixtures with Klebsiella oxytoca, an NEC-positive-associated pathogen. Overall, the synbiotic mixtures of digested Tc-WS-NSP-ICE and high bacterial concentrations of L. acidophilus (5.57 × 10⁹), B. breve (2.7 × 10⁸ CFU/mL), and B. infantis (1.53 × 10⁸) demonstrated higher (42.0%, 45.0%, 43.1%, respectively) ability to downregulate IL-8 compared to the sole use of Tc-WS-NSPs (24.5%), or the probiotics L. acidophilus (32.3%), B. breve (37.8%), or B. infantis (33.1%). The ability demonstrated by the Tc-WS-NSPs, the probiotics, and their synbiotics mixtures to downregulate IL-8 production in the presence of an NEC-positive-associated pathogen may be useful in the development of novel prophylactic agents against NEC.

The Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P): A research program striving to improve blood donor safety and optimize transfusion outcomes across the lifespan

BACKGROUND

The Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) is a new iteration of prior National Heart, Lung, and Blood Institute (NHLBI) REDS programs that focus on improving transfusion recipient outcomes across the lifespan as well as the safety and availability of the blood supply.

STUDY DESIGN AND METHODS

The US program includes blood centers and hospitals (22 including 6 free-standing Children's hospitals) in four geographic regions. The Brazilian program has 5 participating hemocenters. A Center for Transfusion Laboratory Studies (CTLS) and a Data Coordinating Center (DCC) support synergistic studies and activities over the 7-year REDS-IV-P program.

RESULTS

The US is building a centralized, vein-to-vein (V2V) database, linking information collected from blood donors, their donations, the resulting manufactured components, and data extracts from hospital electronic medical records of transfused and non-transfused patients. Simultaneously, the Brazilian program is building a donor, donation, and component database. The databases will serve as the backbone for retrospective and prospective observational studies in transfusion epidemiology, transfusion recipient outcomes, blood component quality, and emerging blood safety issues. Special focus will be on preterm infants, patients with sickle cell disease, thalassemia or cancer, and the effect of donor biologic variability and component manufacturing on recipient outcomes. A rapid response capability to emerging safety threats has resulted in timely studies related to Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2).

CONCLUSIONS

The REDS-IV-P program endeavors to improve donor-recipient-linked research with a focus on children and special populations while also maintaining the flexibility to address emerging blood safety issues.

Effect of washed versus unwashed red blood cells on transfusion-related immune responses in preterm newborns

Objectives

Transfusion with washed packed red blood cells (PRBCs) may be associated with reduced transfusion‐related pro‐inflammatory cytokine production. This may be because of alterations in recipient immune responses.

Methods

This randomised trial evaluated the effect of transfusion with washed compared with unwashed PRBCs on pro‐inflammatory cytokines and endothelial activation in 154 preterm newborns born before 29 weeks’ gestation. Changes in plasma cytokines and measures of endothelial activation in recipient blood were analysed after each of the first three transfusions.

Results

By the third transfusion, infants receiving unwashed blood had an increase in IL‐17A (P = 0.04) and TNF (P = 0.007), whereas infants receiving washed blood had reductions in IL‐17A (P = 0.013), TNF (P = 0.048), IL‐6 (P = 0.001), IL‐8 (P = 0.037), IL‐12 (P = 0.001) and IFN‐γ (P = 0.001). The magnitude of the post‐transfusion increase in cytokines did not change between the first and third transfusions in the unwashed group but decreased in the washed group for IL‐12 (P = 0.001), IL‐17A (P = 0.01) and TNF (P = 0.03), with the difference between the groups reaching significance by the third transfusion (P < 0.001 for each cytokine).

Conclusion

The pro‐inflammatory immune response to transfusion in preterm infants can be modified when PRBCs are washed prior to transfusion. Further studies are required to determine whether the use of washed PRBCs for neonatal transfusion translates into reduced morbidity and mortality.

The short-term effects of RBC transfusions on intestinal injury in preterm infants

BACKGROUND

Anemic preterm infants may require red blood cell (RBC) transfusions to maintain sufficient oxygen supply to vital organs. Transfusion treatment, however, may have adverse intestinal effects. We aimed to investigate the short-term effects of RBC transfusions, hypothesizing to find signs of oxidative stress and intestinal injury, possibly related to levels of splanchnic (re-)oxygenation.

METHODS

We prospectively included preterm infants (gestational age < 32 weeks). We measured urinary biomarkers for oxidative stress (8-isoprostane) and intestinal cell injury (intestinal fatty acid-binding protein, I-FABP) shortly before and after RBC transfusion. Splanchnic oxygen saturation (r_sSO₂) and r_sSO₂ variability were assessed simultaneously.

RESULTS

Twenty-nine preterm infants received 58 RBC transfusions at various postnatal ages. Six of them developed necrotizing enterocolitis (NEC) after transfusion. Urinary 8-isoprostane and I-FABP increased following RBC transfusion (median 282-606 pg/ml and 4732-6968 pg/ml, p < 0.01), more pronounced in infants who developed NEC. Change in I-FABP correlated with change in 8-isoprostane (rho = 0.623, p < 0.01). Lower r_sSO₂ variability, but not higher mean r_sSO₂ was associated with higher 8-isoprostane and I-FABP levels after transfusion.

CONCLUSIONS

Preterm RBC transfusions are associated with concomitant signs of oxidative stress and intestinal injury, parallel with lower variability in splanchnic oxygenation. This may represent the early pathogenetic process of transfusion-associated NEC.

IMPACT

Red blood cell (RBC) transfusions in preterm infants are associated with a near 2-fold increase in urinary biomarkers for oxidative stress (8-isoprostane) and intestinal cell injury (intestinal fatty acid-binding protein, I-FABP). Magnitude of change in I-FABP strongly correlated with the magnitude of 8-isoprostane change, suggesting a role for oxidative stress in the pathogenesis of intestinal injury. Lower splanchnic oxygen saturation variability following RBC transfusion was associated with higher 8-isoprostane and I-FABP levels. Loss of splanchnic variability after RBC transfusion may result from increased oxidative stress and its concomitant intestinal injury, possibly representing the early pathogenetic process of transfusion-associated necrotizing enterocolitis.

Neonatal anemia relates to intestinal injury in preterm infants

BACKGROUND

Anemia is associated with decreased tissue oxygenation in preterm infants and may contribute to developing necrotizing enterocolitis (NEC). We aimed to investigate whether hemoglobin level is associated with intestinal injury, by comparing anemic infants 10 days prior to red blood cell (RBC) transfusion with non-anemic controls.

METHODS

A nested case-control study in which we matched anemic preterms (gestational age (GA) < 32 weeks) with non-anemic controls (1:1), based on GA, birth weight (BW), and postnatal age. We measured urinary intestinal fatty acid-binding protein, I-FABP, marker for intestinal injury, twice weekly. Simultaneously, we assessed splanchnic oxygen saturation (r_sSO₂) and r_sSO₂ variability.

RESULTS

Thirty-six cases and 36 controls were included (median GA 27.6 weeks, BW 1020 grams). Median I-FABP level was higher in cases from 6 days to 24-h before transfusion (median ranging: 4749-8064 pg/ml versus 2194-3751 pg/ml). R_sSO₂ and r_sSO₂ variability were lower in cases than controls shortly before transfusion. Hemoglobin levels correlated negatively with r_sSO₂ and r_sSO₂ variability in cases, and negatively with I-FABP in cases and controls together.

CONCLUSIONS

Urinary I-FABP levels were higher in anemic infants before RBC transfusion than in non-anemic matched controls, suggesting intestinal injury associated with anemia. This may predispose to NEC in some anemic preterm infants.

IMPACT

Anemia is a common comorbidity in preterm infants and may lead to impaired splanchnic oxygen saturation and intestinal tissue hypoxia, a proposed mechanism for NEC. Lower hemoglobin level is associated with higher urinary I-FABP levels, a marker for intestinal injury, both in anemic preterm infants and in cases and controls together. Lower splanchnic oxygen saturation and reduction of its variability are associated with higher urinary I-FABP levels in anemic preterm infants before their first RBC transfusion. These results support the hypothesis that anemia in very preterm infants results in intestinal cell injury, which may precede NEC development in some.

Assessment of synthetic red cell therapy for extremely preterm ovine fetuses maintained on an artificial placenta life-support platform

BACKGROUND

Artificial placenta therapy (APT) is an experimental care strategy for extremely preterm infants born at 21-24 weeks' gestation. In our previous studies, blood taken from the maternal ewe was used as the basis of priming solutions for the artificial placenta circuit. However, the use of maternal blood as a priming solution is accompanied by several challenges. We explored the use of synthetic red cells (hemoglobin vesicles; HbV) as the basis of a priming solution for APT used to manage extremely early preterm ovine fetuses.

METHODS

Six ewes with singleton pregnancies at 95 d gestation (term = 150 d) were adapted to APT and maintained with constant monitoring of key vital parameters. The target maintenance period was 72 h in duration. A synthetic red cell solution consisting of HbV, sheep albumin and electrolytes was used as priming solutions for the APT circuit. Fetuses were evaluated on gross appearance, physiological parameters and bleeding after euthanasia.

RESULTS

Two out of six APT fetuses were successfully maintained for the targeted 72 h experimental period with controllable anemia (>10 g/dl) and methemoglobinemia (<10%) using an infusion of blood transfusion and nitroglycerin delivered >1 h after APT commencement, a sufficient period of time to cross-match blood products and screen for viral agents of concern.

CONCLUSIONS

Extremely preterm sheep fetuses were maintained for a period of up to 72 h using APT in combination with circuit priming using a synthetic red cell (HbV) preparation. Although significant further refinements are required, these findings demonstrated the potential clinical utility of synthetic blood products in the eventual clinical translation of artificial placenta technology to support extremely preterm infants.

The association of severe anemia, red blood cell transfusion and necrotizing enterocolitis in neonates

Background

The relationship between severe anemia, red blood cell transfusion and Neonatal necrotizing enterocolitis (NEC) remains controversial. The purpose of this study was to determine the association of severe anemia and RBC transfusion with NEC in neonates.

Methods

The clinical characteristics of NEC were observed in 467 infants with different birth weights from January 2012 to July 2020. A 1:1 ratio case-control study was performed in very low birth weight (VLBW) infants. Severe anemia, RBC transfusion, and confounding factors, including maternal and perinatal complications, feeding, and antibiotics administration were collected in both groups. Univariate and multivariate analyses were used to investigate effects on the risk of NEC.

Results

The day of NEC onset and mortality were inversely associated with birth weight. In VLBW infants, adjusting for other factors, severe anemia within 72 h [OR = 2.404, P = 0.016], RBC transfusion within 24 h [OR = 4.905, P = 0.016], within 48 h [OR = 5.587, P = 0.008], and within 72 h [OR = 2.858, P = 0.011] increased the risk of NEC.

Conclusion

Both severe anemia and RBC transfusion appears to increase the risk of NEC in VLBW infants. The early prevention and treatment of anemia, strict evaluation of the indications for transfusion and enhanced monitoring after transfusion is encouraged in the NICU.

Transfusion-associated necrotizing enterocolitis (NEC) in extremely preterm infants: experience of a tertiary neonatal center in UK

OBJECTIVE

To compare the characteristics and short-term outcomes in extremely preterm infants, who developed necrotizing enterocolitis (NEC) following a packed red blood cell transfusion (pRBC) within 48 h (TANEC), with those who developed NEC beyond 48 h (non-TANEC).

SETTING

A single-center retrospective cohort study in a Tertiary neonatal intensive care unit in the UK over a 5-year period.

PATIENTS AND METHODS

Extremely premature infants (23-27 weeks gestation) were selected. TANEC and non-TANEC incidence were calculated from the confirmed NEC group (defined as modified Bell's stage II and beyond). The characteristics and short-term outcomes of infants with TANEC in the first 8 weeks of life were compared to infants with non-TANEC.

RESULTS AND INTERPRETATION

Incidence of confirmed NEC was 14% (28/207). On further subgroup analysis of the confirmed NEC cases, 46% (13/28) of infants were identified with TANEC and 54% (15/28) with non-TANEC. The incidence of TANEC did not correlate with the number of antecedent pRBC transfusions or the pre-transfusion median hemoglobin (Hb) levels. There were no significant differences in characteristics between the TANEC and non-TANEC groups. Infants within the TANEC group required more intensive neonatal care support, greater surgical intervention (p-value 0.043) with loss of gut integrity and an increase in number of TPN dependency days (p-value 0.014).

CONCLUSIONS

A significantly worse clinical course and short-term outcome was observed in the TANEC group when compared with the non-TANEC group.

Respiratory Severity Score greater than or equal to 2 at birth is associated with an increased risk of mortality in infants with birth weights less than or equal to 1250 g

OBJECTIVE

Respiratory Severity Score (RSS), the product of mean airway pressure and the fraction of inspired oxygen may estimate the severity of neonatal lung disease. We aimed to determine if RSS on the first day of life is associated with mortality and/or comorbidities in infants born less than or equal to 1250 g.

METHODS

Data were extracted from the NYS Perinatal Data System for premature inborn infants from 2006 to 2016 born between 400 and 1250 g (N = 730). RSS was divided into three categories: less than 2 (low, n = 310), 2-5 (moderate, n = 265), greater than 5 (high, n = 155). The primary outcome was mortality. Logistic regression determined associations with composite outcomes of death or respiratory morbidity (respiratory support after 36 weeks postmenstrual age), death or neurologic morbidity (periventricular leukomalacia) or high-grade intraventricular hemorrhage), and death/severe morbidity (death or neurologic morbidity or respiratory morbidity or stage ≥ III retinopathy of prematurity or necrotizing enterocolitis) by RSS category.

RESULTS

Birthweight and gestational age were lower with the increasing RSS category (p < .001 for both). Mode of delivery, antenatal steroids, and maternal age did not differ by RSS. In adjusted analyses, there were increased odds of mortality in infants with moderate RSS (odds ratio [95% confidence intervals]: 3.1 (1.7-5.4) and high 4.5 (2.5-8.2). These groups had higher odds of death or respiratory morbidity, death or neurologic morbidity, and death/severe morbidity.

CONCLUSION

Higher RSS (≥2) is associated with an increased risk of mortality and morbidities in infants born less than or equal to 1250 g.

Neonatal red blood cell transfusion

Transfusions are more common in premature infants with approximately 40% of low birth weight infants and up to 90% of extremely low birth weight infants requiring red blood cell transfusion. Although red blood cell transfusion can be life-saving in these preterm infants, it has been associated with higher rates of complications including necrotizing enterocolitis, bronchopulmonary dysplasia, retinopathy of prematurity and possibly abnormal neurodevelopment. The main objective of this review is to assess current red blood cell transfusion practices in the neonatal intensive care unit, to summarize available neonatal transfusion guidelines published in different countries and to emphasize the wide variation in transfusion thresholds that exists for red blood cell transfusion. This review also addresses certain issues specific to red blood cell processing for the neonatal population including storage time, irradiation, cytomegalovirus (CMV) prevention strategies and patient blood management. Future research avenues are proposed to better define optimal transfusion practice in neonatal intensive care units.

Abnormal Splanchnic Regional Saturations in a Preterm Infant That Developed Necrotizing Enterocolitis Following a Red Blood Cell Transfusion

BACKGROUND

Necrotizing enterocolitis (NEC) has been associated with red blood cell (RBC) transfusions in preterm infants. Near-infrared spectroscopy (NIRS) can be used to noninvasively monitor regional oxygen saturations (rSO2).

CLINICAL FINDINGS

This former 28-week female premature infant, 29 days old, received an RBC transfusion due to increased apneic spells and a hematocrit of 27%. Within 24 hours she developed abdominal distension and passed a bloody stool (Bell's stage 2 NEC on abdominal x-ray). She completed 7 days of antibiotics and nothing-by-mouth status and was discharged home on room air and oral feedings on day of life 70.

PRIMARY DIAGNOSIS

We describe the presentation of NEC following a RBC transfusion in a preterm infant monitored with cerebral and splanchnic NIRS.

INTERVENTIONS

Mean rSO2 (cerebral and splanchnic) measurements were continuously recorded and calculated in 30-minute periods at baseline (prior to packed RBC transfusion), every hour during the RBC transfusion, and every 3 hours for the following 48 hours.

OUTCOMES

In this infant, average baseline splanchnic rSO2 was low at 46.5%, and increased during transfusion to 65%. However, following the RBC transfusion and an enteral feeding, splanchnic rSO2 dramatically decreased to 26%, and remained low until the time of NEC diagnosis.

PRACTICE RECOMMENDATIONS

To develop awareness of the increased risk for NEC in premature infants with significant anemia that receive packed RBC transfusions. With further studies and education, NIRS could be a valuable tool for the nurses and medical team to identify these at-risk neonates.

Effects of Liberal vs Restrictive Transfusion Thresholds on Survival and Neurocognitive Outcomes in Extremely Low-Birth-Weight Infants: The ETTNO Randomized Clinical Trial

IMPORTANCE

Red blood cell transfusions are commonly administered to infants weighing less than 1000 g at birth. Evidence-based transfusion thresholds have not been established. Previous studies have suggested higher rates of cognitive impairment with restrictive transfusion thresholds.

OBJECTIVE

To compare the effect of liberal vs restrictive red blood cell transfusion strategies on death or disability.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial conducted in 36 level III/IV neonatal intensive care units in Europe among 1013 infants with birth weights of 400 g to 999 g at less than 72 hours after birth; enrollment took place between July 14, 2011, and November 14, 2014, and follow-up was completed by January 15, 2018.

INTERVENTIONS

Infants were randomly assigned to liberal (n = 492) or restrictive (n = 521) red blood cell transfusion thresholds based on infants' postnatal age and current health state.

MAIN OUTCOME AND MEASURES

The primary outcome, measured at 24 months of corrected age, was death or disability, defined as any of cognitive deficit, cerebral palsy, or severe visual or hearing impairment. Secondary outcome measures included individual components of the primary outcome, complications of prematurity, and growth.

RESULTS

Among 1013 patients randomized (median gestational age at birth, 26.3 [interquartile range {IQR}, 24.9-27.6] weeks; 509 [50.2%] females), 928 (91.6%) completed the trial. Among infants in the liberal vs restrictive transfusion thresholds groups, respectively, incidence of any transfusion was 400/492 (81.3%) vs 315/521 (60.5%); median volume transfused was 40 mL (IQR, 16-73 mL) vs 19 mL (IQR, 0-46 mL); and weekly mean hematocrit was 3 percentage points higher with liberal thresholds. Among infants in the liberal vs restrictive thresholds groups, the primary outcome occurred in 200/450 (44.4%) vs 205/478 (42.9%), respectively, for a difference of 1.6% (95% CI, -4.8% to 7.9%; P = .72). Death by 24 months occurred in 38/460 (8.3%) vs 44/491 (9.0%), for a difference of -0.7% (95% CI, -4.3% to 2.9%; P = .70), cognitive deficit was observed in 154/410 (37.6%) vs 148/430 (34.4%), for a difference of 3.2% (95% CI, -3.3% to 9.6%; P = .47), and cerebral palsy occurred in 18/419 (4.3%) vs 25/443 (5.6%), for a difference of -1.3% (95% CI, -4.2% to 1.5%; P = .37), in the liberal vs the restrictive thresholds groups, respectively. In the liberal vs restrictive thresholds groups, necrotizing enterocolitis requiring surgical intervention occurred in 20/492 (4.1%) vs 28/518 (5.4%); bronchopulmonary dysplasia occurred in 130/458 (28.4%) vs 126/485 (26.0%); and treatment for retinopathy of prematurity was required in 41/472 (8.7%) vs 38/492 (7.7%). Growth at follow-up was also not significantly different between groups.

CONCLUSIONS AND RELEVANCE

Among infants with birth weights of less than 1000 g, a strategy of liberal blood transfusions compared with restrictive transfusions did not reduce the likelihood of death or disability at 24 months of corrected age.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01393496.

Erythropoietin prevents necrotizing enterocolitis in very preterm infants: a randomized controlled trial

Background

Necrotizing enterocolitis (NEC) is one of the most severe complications in very preterm infants, but there are currently no accepted methods to prevent NEC. Studies have shown that erythropoietin (EPO) has the potential to prevent NEC or improve outcomes of preterm NEC. This study aimed to determine whether recombinant human EPO (rhEPO) could protect against NEC in very preterm infants.

Methods

The study was a prospective randomized clinical trial performed among four NICU centers. A total of 1327 preterm infants with gestational age ≤ 32 weeks were admitted to the centers, and 42 infants were excluded leaving 1285 eligible infants to be randomized to the rhEPO or control group. Infants in the rhEPO group were given 500 IU/kg rhEPO intravenously every other day for 2 weeks, while the control group was given the same volume of saline. The primary outcome was the incidence of NEC in very preterm infants at 36 weeks of corrected gestational age.

Results

A total of 1285 infants were analyzed at 36 weeks of corrected age for the incidence of NEC. rhEPO treatment significantly decreased the incidence of NEC (stage I, II and III) (12.0% vs. 17.1%, p = 0.010), especially confirmed NEC (stage II and III) (3.0% vs. 5.4%, p = 0.027). Meanwhile, rhEPO treatment significantly reduced the number of red blood cells transfusion in the confirmed NEC cases (1.2 ± 0.4 vs. 2.7 ± 1.0, p = 0.004). Subgroup analyses showed that rhEPO treatment significantly decreased the incidence of confirmed NEC at gestational age < 28 weeks (p = 0.019), and the incidence of all stages NEC in preterm infants with hemoglobin < 90 g/l (p = 0.000) and 5 min Apgar score > 5 (p = 0.028).

Conclusion

Repeated low-dose rhEPO treatment is beneficial against NEC in very preterm infants.

Trial registration The protocol was registered retrospectively at ClinicalTrials.gov (NCT03919500) on April 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03919500

FEEding DURing red cell transfusion (FEEDUR RCT): a multi-arm randomised controlled trial

Background

Necrotising Enterocolitis (NEC) is a devastating neonatal disease. A temporal association between red cell transfusion and NEC has been recognized and there have been concerns about the effects of feeding during transfusion. We aimed to assess the effect of different enteral feeding regimens on splanchnic oxygenation in preterm infants receiving red cell transfusions.

Methods

This was an open, multi-arm, parallel-group, randomised controlled trial conducted in a single centre in Australia. We compared three different enteral feeding regimes during a single red cell transfusion in preterm infants < 35 weeks gestational age at birth. Infants were randomised to either: (1) Withholding enteral feeds for 12 h from the start of transfusion or; (2) Continuing enteral feeds or; (3) Restriction of enteral feed volume to 120 ml/kg/day (maximum 20 kcal/30 ml) for 12 h. The primary outcome was mean splanchnic-cerebral oxygenation ratio (SCOR) and mean splanchnic fractional oxygen extraction (FOE) before (1 h prior), during (1 h into transfusion) and after (end of transfusion; 12 and 24 h post) transfusion.

Results

There were 60 transfusion episodes (20 transfusion episodes in each group) included in the analysis. 41 infants with a median gestational age at birth of 27 weeks (range 23–32 weeks) were enrolled. The median postnatal age was 43 days (range 19–94 days) and the median pre-transfusion haematocrit was 0.27 (range 0.22–0.32). All three groups were similar at baseline. There were no differences in mean SCOR and mean splanchnic FOE at any of the pre-specified time points. There were also no differences in clinical outcomes. There were no episodes of NEC in any infant. Across all groups the mean SCOR increased from the start to the end of each transfusion (0.97 [CI95% 0.96–0.98] vs 1.00 [CI95% 0.99–1.01]; p = 0.04) and the mean FOE decreased from the start to the end of each transfusion (0.22 [CI95% 0.21–0.23] vs 0.17 [CI95% 0.16–0.18]; p < 0.001).

Conclusions

There were no differences in splanchnic oxygenation when enteral feeds were either withheld, continued or restricted during a transfusion. However, the successful conduct of this study supports the feasibility of a large trial powered to assess clinical outcomes.

Trial registration

ANZCTR, ACTRN12616000160437. Registered 10 February 2016, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370069

Iron Homeostasis Disruption and Oxidative Stress in Preterm Newborns

Iron is an essential micronutrient for early development, being involved in several cellular processes and playing a significant role in neurodevelopment. Prematurity may impact on iron homeostasis in different ways. On the one hand, more than half of preterm infants develop iron deficiency (ID)/ID anemia (IDA), due to the shorter duration of pregnancy, early postnatal growth, insufficient erythropoiesis, and phlebotomy losses. On the other hand, the sickest patients are exposed to erythrocytes transfusions, increasing the risk of iron overload under conditions of impaired antioxidant capacity. Prevention of iron shortage through placental transfusion, blood-sparing practices for laboratory assessments, and iron supplementation is the first frontier in the management of anemia in preterm infants. The American Academy of Pediatrics recommends the administration of 2 mg/kg/day of oral elemental iron to human milk-fed preterm infants from one month of age to prevent ID. To date, there is no consensus on the type of iron preparations, dosages, or starting time of administration to meet optimal cost-efficacy and safety measures. We will identify the main determinants of iron homeostasis in premature infants, elaborate on iron-mediated redox unbalance, and highlight areas for further research to tailor the management of iron metabolism.

Early erythropoiesis-stimulating agents in preterm or low birth weight infants

BACKGROUND

Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia and to provide neuro protection and protection against necrotising enterocolitis (NEC). Darbepoetin (Darbe) and EPO are currently available ESAs.

OBJECTIVES

To assess the effectiveness and safety of ESAs (erythropoietin (EPO) and/or Darbe) initiated early (before eight days after birth) compared with placebo or no intervention in reducing red blood cell (RBC) transfusions, adverse neurological outcomes, and feeding intolerance including necrotising enterocolitis (NEC) in preterm and/or low birth weight infants. Primary objective for studies that primarily investigate the effectiveness and safety of ESAs administered early in reducing red blood cell transfusions: To assess the effectiveness and safety of ESAs initiated early in reducing red blood cell transfusions in preterm infants. Secondary objectives: Review authors performed subgroup analyses of low (≤ 500 IU/kg/week) and high (> 500 IU/kg/week) doses of EPO and the amount of iron supplementation provided: none, low (≤ 5 mg/kg/d), and high (> 5 mg/kg/d). Primary objective for studies that primarily investigate the neuro protective effectiveness of ESAs: To assess the effectiveness and safety of ESAs initiated early in reducing adverse neurological outcomes in preterm infants. Primary objective for studies that primarily investigate the effectiveness of EPO or Darbe administered early in reducing feeding intolerance: To assess the effectiveness and safety of ESAs administered early in reducing feeding intolerance (and NEC) in preterm infants. Other secondary objectives: To compare the effectiveness of ESAs in reducing the incidence of adverse events and improving long-term neurodevelopmental outcomes.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE via PubMed (1966 to 10 March 2017), Embase (1980 to 10 March 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 10 March 2017). We searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised and quasi-randomised controlled trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of early initiation of EAS treatment versus placebo or no intervention in preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

We used the methods described in the Cochrane Handbook for Systematic Reviews of Interventions and the GRADE approach to assess the quality of evidence.

MAIN RESULTS

This updated review includes 34 studies enrolling 3643 infants. All analyses compared ESAs versus a control consisting of placebo or no treatment. Early ESAs reduced the risk of 'use of one or more [red blood cell] RBC transfusions' (typical risk ratio (RR) 0.79, 95% confidence interval (CI) 0.74 to 0.85; typical risk difference (RD) -0.14, 95% CI -0.18 to -0.10; I2 = 69% for RR and 62% for RD (moderate heterogeneity); number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 6 to 10; 19 studies, 1750 infants). The quality of the evidence was low. Necrotising enterocolitis was significantly reduced in the ESA group compared with the placebo group (typical RR 0.69, 95% CI 0.52 to 0.91; typical RD -0.03, 95% CI -0.05 to -0.01; I2 = 0% for RR and 22% for RD (low heterogeneity); NNTB 33, 95% CI 20 to 100; 15 studies, 2639 infants). The quality of the evidence was moderate. Data show a reduction in 'Any neurodevelopmental impairment at 18 to 22 months' corrected age in the ESA group (typical RR 0.62, 95% CI 0.48 to 0.80; typical RD -0.08, 95% CI -0.12 to -0.04; NNTB 13, 95% CI 8 to 25. I2 = 76% for RR (high heterogeneity) and 66% for RD (moderate); 4 studies, 1130 infants). The quality of the evidence was low. Results reveal increased scores on the Bayley-II Mental Development Index (MDI) at 18 to 24 months in the ESA group (weighted mean difference (WMD) 8.22, 95% CI 6.52 to 9.92; I2 = 97% (high heterogeneity); 3 studies, 981 children). The quality of the evidence was low. The total volume of RBCs transfused per infant was reduced by 7 mL/kg. The number of RBC transfusions per infant was minimally reduced, but the number of donors to whom infants who were transfused were exposed was not significantly reduced. Data show no significant difference in risk of stage ≥ 3 retinopathy of prematurity (ROP) with early EPO (typical RR 1.24, 95% CI 0.81 to 1.90; typical RD 0.01, 95% CI -0.02 to 0.04; I2 = 0% (no heterogeneity) for RR; I2 = 34% (low heterogeneity) for RD; 8 studies, 1283 infants). Mortality was not affected, but results show significant reductions in the incidence of intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL).

AUTHORS' CONCLUSIONS

Early administration of ESAs reduces the use of red blood cell (RBC) transfusions, the volume of RBCs transfused, and donor exposure after study entry. Small reductions are likely to be of limited clinical importance. Donor exposure probably is not avoided, given that all but one study included infants who had received RBC transfusions before trial entry. This update found no significant difference in the rate of ROP (stage ≥ 3) for studies that initiated EPO treatment at less than eight days of age, which has been a topic of concern in earlier versions of this review. Early EPO treatment significantly decreased rates of IVH, PVL, and NEC. Neurodevelopmental outcomes at 18 to 22 months and later varied in published studies. Ongoing research should evaluate current clinical practices that will limit donor exposure. Promising but conflicting results related to the neuro protective effect of early EPO require further study. Very different results from the two largest published trials and high heterogeneity in the analyses indicate that we should wait for the results of two ongoing large trials before drawing firm conclusions. Administration of EPO is not currently recommended because limited benefits have been identified to date. Use of darbepoetin requires further study.

Association of Bolus Feeding With Splanchnic and Cerebral Oxygen Utilization Efficiency Among Premature Infants With Anemia and After Blood Transfusion

IMPORTANCE

The pathogenesis of transfusion-associated necrotizing enterocolitis remains elusive. Splanchnic hypoperfusion associated with packed red blood cell transfusion (PRBCT) and feeding has been implicated, but studies of splanchnic tissue oxygenation with respect to feeding plus PRBCT are lacking.

OBJECTIVE

To investigate the oxygen utilization efficiency of preterm gut and brain challenged with bolus feeding during anemia and after transfusion using near-infrared spectroscopy.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study conducted from September 1, 2014, to November 30, 2016, at a tertiary neonatal intensive care unit included 25 hemodynamically stable infants with gestational age less than 32 weeks, birth weight less than 1500 g, and postmenstrual age younger than 37 weeks. Data analysis was performed from August 1, 2017, to October 31, 2018.

EXPOSURES

Infants received PRBCT (15 mL/kg for 4 hours) and at least 120 mL/kg daily of second hourly bolus feedings.

MAIN OUTCOMES AND MEASURES

Splanchnic fractional tissue oxygen extraction (FTOEs) and cerebral fractional tissue oxygen extraction (FTOEc) measures were made during 75-minute feeding cycles that comprised a 15-minute preprandial feeding phase (FP0) and 4 contiguous 15-minute postprandial feeding phases (FP1, FP2, FP3, and FP4; each 15 minutes long). The intraindividual comparisons of feeding-related changes were evaluated during the pretransfusion epoch (TE0: 4 hours before onset of transfusion) and 3 TEs after transfusion (TE1: first 8 hours after PRBCT completion; TE2: 9-16 hours after PRBCT completion; and TE3: 17-24 hours after PRBCT completion).

RESULTS

Of 25 enrolled infants (13 [52%] female; median birth weight, 949 g [interquartile range {IQR}, 780-1100 g]; median gestational age, 26.9 weeks [IQR, 25.9-28.6 weeks]; median enrollment weight, 1670 g [IQR, 1357-1937 g]; and median postmenstrual age, 34 weeks [IQR, 32.9-35 weeks]), 1 infant was excluded because of corrupted near-infrared spectroscopy data. No overall association was found between FTOEs and FPs in a multivariable repeated-measures model that accounted for transfusion epochs (primary analysis approach) (FP0: mean estimate, 11.64; 95% CI, 9.55-13.73; FP1: mean estimate, 12.02; 95% CI, 9.92-14.11; FP2: mean estimate, 12.77; 95% CI, 10.68-14.87; FP3: mean estimate, 12.54; 95% CI, 10.45-14.64; FP4: mean estimate, 12.98; 95% CI, 10.89-15.08; P = .16 for the FP association). However exploratory analyses of postprandial changes in FTOEs undertaken for each transfusion epoch separately found evidence of increased postprandial FTOEs during TE1 (mean [SD] FTOEs, 10.55 [5.5] at FP0 vs 13.21 [5.96] at FP4, P = .046). The primary and exploratory analyses found no association between FTOEc and feeding phases, suggesting that cerebral oxygenation may be protected.

CONCLUSIONS AND RELEVANCE

The findings suggest that enteral feeding may be associated with gut ischemia and potentially transfusion-associated necrotizing enterocolitis. The postprandial changes in FTOEs appear to warrant further investigation in larger randomized studies.

Effect of red blood cell transfusion on short-term outcomes in very low birth weight infants

BACKGROUND

Red blood cell (RBC) transfusion improves cardiorespiratory status of preterm infants by increasing circulating hemoglobin, improving tissue oxygenation, and reducing cardiac output. However, RBC transfusion itself has also been suggested to negatively affect short-term outcomes such as intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), and necrotizing enterocolitis (NEC) in premature infants.

PURPOSE

This study aimed to analyze the relationship between RBC transfusion and short-term outcomes in very low birth weight (VLBW) infants (birth weight, <1,500 g).

METHODS

We retrospectively reviewed the medical records of VLBW infants admitted to the Soonchunhyang University Bucheon Hospital between October 2010 and December 2017. Infants who died during hospitalization were excluded. The infants were divided into 2 groups according to RBC transfusion status. We investigated the relationship between RBC transfusion and short-term outcomes including BPD, ROP, NEC, and IVH.

RESULTS

Of the 250 enrolled VLBW infants, 109 (43.6%) underwent transfusion. Univariate analysis revealed that all shortterm outcomes except early-onset sepsis and patent ductus arteriosus were associated with RBC transfusion. In multivariate analysis adjusted for gestational age, birth weight and Apgar score at 1 minute, RBC transfusion was significantly correlated with BPD (odds ratio [OR], 5.42; P<0.001) and NEC (OR, 3.40; P= 0.009).

CONCLUSION

RBC transfusion is significantly associated with adverse clinical outcomes such as NEC and BPD in VLBW infants. Careful consideration of the patient's clinical condition and appropriate guidelines is required before administration of RBC transfusions.

Stopping enteral feeds for prevention of transfusion-associated necrotising enterocolitis in preterm infants

BACKGROUND

Feeding practices around the time of packed red blood cell transfusion have been implicated in the subsequent development of necrotising enterocolitis (NEC) in preterm infants. Specifically, it has been suggested that withholding feeds around the time of transfusion may reduce the risk of subsequent NEC. It is important to determine if withholding feeds around transfusion reduces the risk of subsequent NEC and associated mortality.

OBJECTIVES

• To assess the benefits and risks of stopping compared to continuing feed management before, during, and after blood transfusion in preterm infants • To assess the effects of stopping versus continuing feeds in the following subgroups of infants: infants of different gestations; infants with symptomatic and asymptomatic anaemia; infants who received different feeding schedules, types of feed, and methods of feed delivery; infants who were transfused with different blood products, at different blood volumes, via different routes of delivery; and those who received blood transfusion with and without co-interventions such as use of diuretics • To determine the effectiveness and safety of stopping feeds around the time of a blood transfusion in reducing the risk of subsequent necrotising enterocolitis (NEC) in preterm infants SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 11), in the Cochrane Library; MEDLINE (1966 to 14 November 2018); Embase (1980 to 14 November 2018); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 14 November 2018). We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised controlled trials (RCTs), cluster-RCTs, and quasi-RCTs.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that compared stopping feeds versus continuing feeds around the time of blood transfusion in preterm infants.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed trial quality, and extracted data from the included studies.

MAIN RESULTS

The search revealed seven studies that assessed effects of stopping feeds during blood transfusion. However, only one RCT involving 22 preterm infants was eligible for inclusion in the review. This RCT had low risk of selection bias but high risk of performance bias, as care personnel were not blinded to the study allocation. The primary objective of this trial was to investigate changes in mesenteric blood flow, and no cases of NEC were reported in any of the infants included in the trial. We were unable to draw any conclusions from this single study. The overall GRADE rating for quality of evidence was very low.

AUTHORS' CONCLUSIONS

Randomised controlled trial evidence is insufficient to show whether stopping feeds has an effect on the incidence of subsequent NEC or death. Large, adequately powered RCTs are needed to address this issue.

Effect of packed red blood cell transfusion on IL-8 and sICAM-1 in premature neonates at different postnatal ages

BACKGROUND

Transfusion-related immunomodulation (TRIM) has been described in adults; however, its existence in neonates is not confirmed. The generation of TRIM is attributed to increased concentrations of IL-8, sICAM-1 and other pro-inflammatory cytokines. This study aimed to monitor changes in IL-8, sICAM-1 as markers for TRIM in premature infants at different postnatal ages.

METHODS

Preterm infants with a gestational age between 28 and 32 weeks who were receiving PRBC transfusion during the first 28 days of life were included in the study. Infants were stratified into two groups according to their postnatal age: Group 1 with postnatal ages of (0-14) days and Group 2 of (15-28) days. The concentrations of IL-8 and sICAM-1 were measured by enzyme-linked immunosorbent assay (ELISA) before transfusion, 6 h after the end of transfusion and in the donor's PRBCs bag immediately before infusion into the baby.

RESULTS

IL-8 concentration in the PRBCs bags correlated with post-transfusion level in Group 2 (r = 0.59, p = 0.002) but not in Group 1 (r = 0.39, p = 0.06). sICAM-1 concentration in the bag correlated with infants'concentrations in neither group. In Group 1, pre-transfusion concentrations of both cytokines (IL-8 and sICAM-1) did not correlate whereas post-transfusion concentrations did correlate (r = -0.09, p = 0.68 and r = 0.4, p = 0.05 respectively). In Group 2, the concentrations of both cytokines did not correlate with each other during pre-transfusion (r = 0.11, p = 0.58) as well as post-transfusion (r = 0.12, p = 0.56). There was no significant increase in either cytokines after transfusion in each group.

CONCLUSION

This study showed positive correlation between IL-8 concentration in the transfusion bag and post transfusion in Group 2 infants which could be attributed to passive transmission from the bags. This study does not support an immune modulatory effect for packed RBC in preterm infants.

Necrotizing Enterocolitis: Enhancing Awareness for the General Practitioner

Necrotizing enterocolitis (NEC) has been recognized for well over 5 decades yet remains the most common life-threatening surgical emergency in the newborn. The incidence of NEC has decreased steadily in preterm and very-low-birthweight infants over several decades and is typically uncommon in term newborns and infants with a birthweight greater than 2,500 g. Evidence accumulating during the past decade, however, suggests that practitioners should consider NEC in this broader subset of term infants with chromosomal and congenital anomalies complicated by heart or gastrointestinal defects when signs and symptoms of feeding intolerance, abdominal illness, or sepsis are present. The short- and long-term consequences of NEC are devastating in all infants, and although early disease recognition and treatment are essential, promoting human milk feeding as a primary modality in prevention is critical. This article highlights our current understanding of the pathophysiology, the clinical presentation, the risk factors for NEC in term infants compared with premature infants, and the treatment of NEC and discusses strategies in the prevention of NEC. Finally, we review the long-term consequences of NEC and the importance of primary care practitioners in the long-term care of infants after hospitalization for NEC.

Impact of red blood cell transfusions on intestinal barrier function in preterm infants

OBJECTIVE

To determine the relationships of red blood cell (RBC) transfusion and enteral feeding to changes in intestinal permeability (IP) measured by the relative intestinal uptake of lactulose (La) and rhamnose (Rh) in preterm infants <33 wk gestation.

DESIGN/METHODS

Infants 240-326wk gestation received La/Rh solution enterally on study days 1, 8 and 15.Urinary La/Rh ratio was measured by HPLC. Hematocrit preceding transfusion, total RBC transfusion volume, volume/kg, and feeding status during each study interval (birth-d1; d1-d8, and d8-d15) were determined.

RESULTS

Of the seventeen (40.5%) subjects who received≥1 transfusion during the study period, 12 (70.6%) infants were <28 wk gestation and 5 (29.4%) infants were≥28 wk gestation, p < 0.0001. Lower pre-transfusion hematocrit was observed in intervals preceding high IP (La/Rh > 0.05) than in intervals preceding low IP (La/Rh≤0.05) measurements (33 vs 35.8, p = 0.1051). RBC transfusions occurred more frequently in intervals preceding high IP than in intervals preceding low IP (26.8%; vs 8.3%, p = 0.0275) with 5-fold higher total RBC volume and volume/kg in intervals preceding any time point with high IP. RBC transfusion during an interval was associated with a three-fold increased risk of high IP (aOR 2.7; 95% C.I 0.564-12.814; p = 0.2143). Exclusive breast milk exposure and post-menstrual age reduced the risk for high IP following RBC transfusion.

CONCLUSIONS

Both RBC transfusion number and volume was associated with subsequent high IP measurements in preterm infants <33 weeks gestation and potentially may contribute to impairment of the preterm intestinal barrier.

The WHEAT pilot trial-WithHolding Enteral feeds Around packed red cell Transfusion to prevent necrotising enterocolitis in preterm neonates: a multicentre, electronic patient record (EPR), randomised controlled point-of-care pilot trial

INTRODUCTION

Necrotising enterocolitis (NEC) is a potentially devastating neonatal disease. A temporal association between red cell transfusion and NEC is well described. Observational data suggest that withholding enteral feeds around red cell transfusions may reduce the risk of NEC but this has not been tested in randomised trials; current UK practice varies. Prevention of NEC is a research priority but no appropriately powered trials have addressed this question. The use of a simplified opt-out consent model and embedding trial processes within existing electronic patient record (EPR) systems provide opportunities to increase trial efficiency and recruitment.

METHODS AND ANALYSIS

We will undertake a randomised, controlled, multicentre, unblinded, pilot trial comparing two care pathways: continuing milk feeds (before, during and after red cell transfusions) and withholding milk feeds (for 4 hours before, during and for 4 hours after red cell transfusions), with infants randomly assigned with equal probability. We will use opt-out consent. A nested qualitative study will explore parent and health professional views. Infants will be eligible if born at <30+0 gestational weeks+days. Primary feasibility outcomes will be rate of recruitment, opt-out, retention, compliance, data completeness and data accuracy; clinical outcomes will include mortality and NEC. The trial will recruit in two neonatal networks in England for 9 months. Data collection will continue until all infants have reached 40+0 corrected gestational weeks or neonatal discharge. Participant identification and recruitment, randomisation and all trial data collection will be embedded within existing neonatal EPR systems (BadgerNet and BadgerEPR); outcome data will be extracted from routinely recorded data held in the National Neonatal Research Database.

ETHICS AND DISSEMINATION

This study holds Research Ethics Committee approval to use an opt-out approach to consent. Results will inform future EPR-embedded and data-enabled trials and will be disseminated through conferences, publications and parent-centred information.

TRIAL REGISTRATION NUMBER

ISRCTN registry ISRCTN62501859; Pre-results.

A murine neonatal model of necrotizing enterocolitis caused by anemia and red blood cell transfusions

Necrotizing enterocolitis (NEC) is an idiopathic, inflammatory bowel necrosis of premature infants. Clinical studies have linked NEC with antecedent red blood cell (RBC) transfusions, but the underlying mechanisms are unclear. Here we report a neonatal murine model to investigate this association. C57BL/6 mouse pups rendered anemic by timed phlebotomy and then given RBC transfusions develop NEC-like intestinal injury with prominent necrosis, inflammation, and submucosal edema/separation of the lamina propria in the ileocecal region and colon within 12-24 h. The anemic intestine is infiltrated by inflammatory macrophages, which are activated in situ by RBC transfusions via a Toll-like receptor (TLR)-4-mediated mechanism and cause bowel injury. Chelation of RBC degradation products with haptoglobin, absence of TLR4, macrophage depletion, and inhibition of macrophage activation is protective. Intestinal injury worsens with increasing severity and the duration of anemia prior to transfusion, indicating a need for the re-evaluation of current transfusion guidelines for premature infants.

Feeding during transfusion and the risk of necrotizing enterocolitis in preterm infants

OBJECTIVE

To evaluate the effect of withholding feeds during transfusion on transfusion associated acute gut injury (TRAGI).

STUDY DESIGN

Data were collected on 125 preterm infants before and after the practice of withholding feeds for 12-24 h during transfusion was instituted. Logistic regression was used to examine effects of withholding feeds on TRAGI rates.

RESULTS

A total of 19 (15%) infants developed NEC; 6/19 (32%) had TRAGI. Postnatal hydrocortisone use was associated with TRAGI (OR 8.97; 95% CI 1.17-68.46, p = 0.034). There was no difference in NEC rates (15.8 vs. 14.7%) and the proportions (22.2 vs. 40%) of TRAGI in the two time periods before and after instituting the standardized feeding regimen and practice of holding feeds during transfusion.

CONCLUSION

No significant decrease was noted in the rates of TRAGI after feeds were withheld during transfusion. Further studies are warranted to explore the relationship between feeds during transfusion and NEC.

Effect of withholding feeds on transfusion-related acute gut injury in preterm infants: a pilot randomized controlled trial

Background: Several retrospective studies have reported an increase in necrotizing enterocolitis (NEC) during the 48 h following red blood cell (RBC) transfusion. Whether withholding enteral feeding during transfusion decreases the risk of transfusion-associated acute gut injury (TRAGI) in preterm infants is unclear.Study design and methods: In this pilot study, 112 preterm infants with gestational age ≤32 weeks and/or birth weight ≤1500 g were randomly assigned to withholding (NPO) or continuance of feeding (FED) during RBC transfusion. Primary outcome measure was development of NEC (stage ≥ 2) within 72 h of a transfusion and the change in abdominal circumference.Results: One hundred fifty-four transfusion episodes (74 NPO and 80 FED) were analyzed. Demographic characteristics were found to be similar in both groups. There was no difference in rates of NEC (0 versus 3.4%; p = .49) between the NPO and FED groups. The incidence of feeding intolerance was higher in the FED group; however, it was statistically insignificant (1.9 versus 6.8%, p = .36). Abdominal circumference remained similar in both groups in all three consecutive days following transfusion (p>.05).Conclusion: This pilot study does not support withholding feedings during transfusion but is not adequately powered to test the hypothesis that NPO decreases NEC rates. Adequately powered well-designed multicenter trials are still required.

Association between hemoglobin concentrations at discharge from the neonatal intensive care unit with markers of neurodevelopmental outcomes in premature neonates

BACKGROUND

Premature neonates are often subjected to multiple transfusions with red blood cells during their hospitalization in the neonatal intensive care unit (NICU). The hemoglobin threshold for transfusion prior to discharge from the NICU varies significantly among different centers. The aim of the present study is to investigate the association between hemoglobin concentration at discharge with neurodevelopmental outcomes in premature neonates.

METHODS

Retrospective observation study with regression analysis was performed with follow up assessment in the neuro-developmental outpatient clinic at 30 months of adjusted age.

RESULTS

Data from 357 neonates born at less than 37 weeks' gestation were analyzed. Sensory and motor neurodevelopment at 30 months of adjusted age, were not associated with the hemoglobin concentration at discharge (p=0.5891 and p=0.4575, respectively). There was no association between the hemoglobin concentration at discharge with fine or gross motor development (p=0.1582 and p=0.3805, respectively). Hemoglobin concentration at discharge was not associated with poor neurodevelopmental outcomes up until 30 months of adjusted age.

CONCLUSIONS

The data of the present study indicate that the hemoglobin concentration of premature neonates at the time of discharge is not associated with poorer markers of neurodevelopmental outcomes at 30 months of adjusted age. Comorbidities such as BPD and IVH that are present to premature neonates were identified as potential risk factors for certain aspects of the neurodevelopment.

Epidemiology of Necrotizing Enterocolitis: New Considerations Regarding the Influence of Red Blood Cell Transfusions and Anemia

This article summarizes available evidence on the relationship between red blood cell transfusion and anemia, and necrotizing enterocolitis (NEC). We review recent studies that highlight the uncertainty of the effect of red blood cell transfusion on NEC and the potential role of anemia. We also discuss potential pathophysiologic effects of both red blood cell transfusion and anemia and highlight strategies to prevent anemia and red blood cell transfusion. We also discuss ongoing randomized trials that are likely to provide important new evidence to guide red blood cell transfusion practices.

Hemodynamics and Perfusion in Premature Infants During Transfusion

BACKGROUND

Premature infants may require packed red blood cell transfusions, but current guidelines lack empirical evidence and vary among institutions and prescribers.

OBJECTIVE

To compare the physiological changes in cardiovascular hemodynamics and oxygen delivery between premature infants with anemia who receive packed red blood cell transfusions and premature infants without anemia.

METHODS

The study was a prospective observational cohort investigation of 75 premature infants. Comparisons among the data were made before, during, and after transfusion in infants with anemia and over time in infants in the control group. In infants with anemia, feedings were withheld 12 hours before and after transfusions.

RESULTS

Electrical cardiometry and near-infrared spectroscopy measurements in premature infants with anemia revealed changes in hemodynamic parameters not detected by standard bedside monitoring. Statistically significant changes were seen before and after transfusions in cardiac output, fractional tissue oxygen extraction, heart rate variability, heart rate complexity, and splanchnic regional tissue oxygen saturation.

CONCLUSION

Bedside monitoring of cardiovascular hemodynamics and oxygen delivery during packed red blood cell transfusion may inform individualized care for the premature infant with anemia and could be useful for the development of evidence-based practice guidelines.

Associations between Red Blood Cell Transfusions and Necrotizing Enterocolitis in Very Low Birth Weight Infants: Ten-Year Data of a Tertiary Neonatal Unit

Background and Objective: Necrotizing enterocolitis (NEC) remains an important cause of mortality in preterm neonates. There are many risk factors for NEC; however, probably the most controversial one is red blood cell transfusions (RBCT). The data concerning the link between NEC and RBCT has been conflicting. Therefore, we aimed to analyze the association between NEC and RBCT in Neonatal Intensive Care Unit (NICU) at the Hospital of Lithuanian University of Health Sciences. Materials and Methods: We used the Very Low Birth Weight (VLBW) Infants database to match all infants with ≥2a Bell’s stage NEC admitted between 1 January 2005 and 31 December 2014 (n = 54) with a control group (n = 54) of similar gestational age and birth weight and without NEC. We analyzed the charts of these infants and performed statistical analysis on 20 clinical variables including RBCT. Results: The main clinical and demographic characteristics did not differ between the two groups. All variables associated with RBCT (receipt of any RBCT, the number of transfusions and the volume transfused in total) were significantly higher in the NEC group both before the onset of NEC and throughout the hospitalization. RBCT increased the odds of NEC even after adjustment for confounding factors. In addition, we found that congenital infection was more abundant in the NEC group and increased the odds of NEC 2.7 times (95% confidence interval CI (1.1, 6.3), p = 0.024). Conclusions: A higher number and the total volume of RBCT are associated with an increased risk of NEC in VLBW infants. The presence of congenital infection might identify the infants at risk.

Pathophysiology of Necrotizing Enterocolitis: An Update

NEC is a devastating disease that, once present, is very difficult to treat. In the absence of an etiologic treatment, preventive measures are required. Advances in decoding the pathophysiology of NEC are being made but a more comprehensive understanding is needed for the targeting of preventative strategies. A better definition of the disease as well as diagnostic criteria are needed to be able to specifically label a disease as NEC. Multiple environmental factors combined with host susceptibility appear to contribute to enhanced risks for developing this disease. Several different proximal pathways are involved, all leading to a common undesired outcome: Intestinal necrosis. The most common form of this disease appears to involve inflammatory pathways that are closely meshed with the intestinal microbiota, where a dysbiosis may result in dysregulated inflammation. The organisms present in the intestinal tract prior to the onset of NEC along with their diversity and functional capabilities are just beginning to be understood. Fulfillment of postulates that support causality for particular microorganisms is needed if bacteriotherapies are to be intelligently applied for the prevention of NEC. Identification of molecular effector pathways that propagate inflammation, understanding of, even incipient role of genetic predisposition and of miRNAs may help solve the puzzle of this disease and may bring the researchers closer to finding a treatment. Despite recent progress, multiple limitations of the current animal models, difficulties related to studies in humans, along with the lack of a "clear" definition will continue to make it a very challenging disease to decipher.