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

Necrotizing enterocolitis comes in different forms: Historical perspectives and defining the disease

The specific cause of what is commonly referred to as necrotizing enterocolitis (NEC) disease has been elusive largely because it is becoming clear that this entity represents more than one disease with multifactorial pathogenic mechanisms. Furthermore, finding clear and consistent diagnostic biomarkers will be difficult until the different subsets of what we are calling this disease are better delineated. In this introductory chapter, we discuss different disease entities that are frequently termed "NEC" in the newborn infant. We hope this will set the stage for more focused research and development of preventative measures for at least the most common forms of this disease.

Umbilical cord blood as a source for red-blood-cell transfusion in neonatology: a systematic review

The prevention and treatment of anaemia in newborn patients made tremendous progress in the last decades. However, red-blood-cell (RBC) transfusions remain unavoidable in many neonates candidate to surgery and especially in preterm infants. In particular, anaemia occurring in neonates born at extremely low gestational age is actually severe and frequently requires transfusions. Several approaches have been explored to prevent or even to reduce the threshold and the frequency of RBC transfusions. Among these, umbilical cord blood (UCB) collection and processing to obtain RBC components for autologous or allogeneic transfusion have been extensively investigated. In this systematic review, we revised the literature concerning the use of UCB for either autologous or allogeneic transfusion purposes and we illustrated the rationale for a transfusion therapy tailored to extremely preterm neonates, based on RBC concentrates from allogeneic UCB donations.

Necrotizing Enterocolitis in Moderate Preterm Infants

Necrotizing enterocolitis (NEC) is a devastating morbidity usually seen in preterm infants, with extremely preterm neonates (EPT ≤28 weeks) considered at highest risk. Moderately preterm infants (MPT 28-34 weeks) constitute a large percentage of NICU admissions. In our retrospective data analysis of NEC in a single regional perinatal center, NEC was observed in 10% of extremely EPT and 7% of MPT, but only 0.7% of late-preterm/term admissions. There was an inverse relationship between postnatal age at onset of NEC and gestational age at birth. Among MPT infants with NEC, maternal hypertensive disorders (29%) and small for gestational age (SGA-15%) were more common than in EPT infants (11.6 and 4.6%, resp.). Congenital gastrointestinal anomalies were common among late preterm/term infants with NEC. SGA MPT infants born to mothers with hypertensive disorders are particularly at risk and should be closely monitored for signs of NEC. Identifying risk factors specific to each gestational age may help clinicians to tailor interventions to prevent NEC.

Characteristics and incidence of transfusion-associated necrotizing enterocolitis in the UK

Background and aims: The etiology of necrotizing enterocolitis (NEC) is unclear and postulated as being multifactorial. It has been suggested that one causative factor is the transfusion of packed red blood cells (PRBCs) leading to the disease entity commonly referred to as transfusion-associated NEC (TANEC). TANEC has been reported in North America but its incidence has not been formally investigated in the UK. Our aims were to identify the incidence of NEC and TANEC in tertiary-level UK neonatal units and to describe characteristics of TANEC cases.Materials and methods: Using strict case definitions for NEC and TANEC, we undertook a retrospective review to estimate the incidence of TANEC cases occurring in four UK tertiary-level centers during a 38-month period.Results: Of 8007 consecutive neonatal admissions of all gestations to the four centers, 68 babies went on to develop NEC and all affected infants were of very low birth weight (VLBW); 34 of these had previously received a transfusion of PRBCs but did not fit the diagnostic criteria for TANEC, whereas 15 (22%) of the 68 babies with NEC qualified as TANEC cases. UK cases occurred at an earlier postnatal age than cases reported in multiple large North American series and were of a lower birth weight.Conclusions: We have confirmed the presence of TANEC in the UK VLBW neonatal population. Its incidence lies within the wide range described in previous reports of this phenomenon globally, though with some local variation in characteristics. Further work is needed to clarify causation, pathophysiology, and possible mechanisms of prevention of TANEC.

Impact of Blood Donor Sex on Transfusion-Related Outcomes in Preterm Infants

OBJECTIVE

Explore the role of red blood cell donor sex on preterm infant neonatal outcomes.

STUDY DESIGN

In a retrospective, exploratory, cohort study, the hospital blood bank database was queried for units of blood released to neonatal intensive care unit patients in 2009-2010. The state blood center provided donor sex, and a department database provided neonatal characteristics and morbidities. Comparisons were made for 2 groups: those who ever received female blood and those who did not.

RESULTS

Among 462 infants <32 weeks of gestation, 190 (41%) received >1 blood transfusion. In univariate analyses, compared with infants who received only male blood, infants who received female donor blood had higher rates of bronchopulmonary dysplasia (38% vs 22%; P = .03), spontaneous intestinal perforation/necrotizing enterocolitis (17% vs 6%; P = .04), and death or any morbidity (60% vs 38%; P < .01), respectively. In adjusted analyses, female blood was associated with any morbidity (P = .0251) and 21 days longer hospitalization (P = .0098). After adding total number transfusions to the model, only an increased number of transfusions was associated with bronchopulmonary dysplasia (P = .0009), any morbidity (P = .0001), and length of stay (P = .0001). In subset regressions comparing exclusively female donor blood with male donor blood, there was a significant interaction of female donor blood and number of transfusions for any morbidity (OR 2.6 95% CI 1.2-5.7, P = .01).

CONCLUSIONS

Preliminary findings suggest that female donor blood was associated with preterm vulnerability to neonatal morbidities.

Transfusion practice in neonates

Neonates, especially extremely low birth weight infants, are among the groups of patients undergoing transfusion frequently. Since they are exposed to higher specific transfusion risks compared to the patients of other age groups, there are many special aspects that must be considered for transfusion therapy in neonates. The transfusion risks in neonates include adverse outcomes specific for preterm infants as well as increased metabolic, immunologic, and infectious complications. To reduce the risks of transfusion-transmitted cytomegalovirus infection and transfusion-associated graft-versus-host disease, leukoreduced and irradiated cellular blood products should be used for all neonates. This review summarizes the risks of neonatal transfusion therapy, specific methods to reduce risk, and current trends and practices of red blood cell and platelet transfusions in neonates, to facilitate decision-making for neonatal transfusion.

Transfusion-associated necrotizing enterocolitis re-evaluated: a systematic review and meta-analysis

CONTEXT

Significant controversy exists surrounding the possible association between recent packed red blood cell (PRBC) transfusion and the subsequent development of necrotizing enterocolitis (NEC) in infants. Previous studies and meta-analyses reporting a statistically significant association led to a practice change to withhold enteral feeds in the peri-transfusion period in many centers in an effort to prevent NEC; however, results from more recent studies do not support the existence of an association and, thus, question the validity of this practice change.

OBJECTIVE

This study aimed to perform a systematic review and meta-analysis to determine whether exposure to recent PRBC transfusion (defined as within 48 h) is associated with the subsequent development of NEC stage ≥II (Bell's criteria) in infants.

METHODS

Medline, Embase, CINAHL, and the Cochrane Library were searched from inception to October 7, 2015. A gray literature search was also performed. Studies comparing the risk of NEC in infants exposed and unexposed to recent PRBC transfusion were included. Thirteen studies met eligibility criteria, and 10 (n=15,675 infants) were included in the meta-analysis. Three authors independently extracted data, and meta-analysis was performed using a random effects model.

RESULTS

We found a statistically significant 45% reduction in the unadjusted odds of NEC in infants exposed to a recent PRBC transfusion (odds ratio=0.55, 95% confidence interval=0.31-0.98).

CONCLUSION

Our results show a protective effect of recent PRBC transfusion on the subsequent development of NEC. The practice of withholding enteral feeds during the peri-transfusion period should be re-evaluated in light of these results.

Does red blood cell irradiation and/or anemia trigger intestinal injury in premature infants with birth weight ≤ 1250 g? An observational birth cohort study

BACKGROUND

Necrotizing enterocolitis (NEC) is a leading cause of neonatal morbidity and mortality in premature infants. To date, no effective biomarkers exist to predict which premature infants will develop NEC, limiting targeted prevention strategies. Multiple observational studies have reported an association between the exposure to red blood cell (RBC) transfusion and/or anemia and the subsequent development of NEC; however, the underlying physiologic mechanisms of how these factors are independently associated with NEC remain unknown.

METHODS

In this paper, we outline our prospective, multicenter observational cohort study of infants with a birth weight ≤ 1250 g to investigate the associations between RBC transfusion, anemia, intestinal oxygenation and injury that lead to NEC. Our overarching hypothesis is that irradiation of RBC units followed by longer storage perturbs donor RBC metabolism and function, and these derangements are associated with paradoxical microvascular vasoconstriction and intestinal tissue hypoxia increasing the risk for injury and/or NEC in transfused premature infants with already impaired intestinal oxygenation due to significant anemia. To evaluate these associations, we are examining the relationship between prolonged irradiation storage time (pIST), RBC metabolomic profiles, and anemia on intestinal oxygenation non-invasively measured by near-infrared spectroscopy (NIRS), and the development of NEC in transfused premature infants.

DISCUSSION

Our study will address a critical scientific gap as to whether transfused RBC characteristics, such as irradiation and metabolism, impair intestinal function and/or microvascular circulation. Given the multifactorial etiology of NEC, preventative efforts will be more successful if clinicians understand the underlying pathophysiologic mechanisms and modifiable risk factors influencing the disease.

TRIAL REGISTRATION

Our study is registered in ClinicalTrials.gov Identifier: NCT02741648 .

Transfusion-associated hazards: A revisit of their presentation

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.

Anemia, red blood cell transfusions, and necrotizing enterocolitis

In the past 15 years, multiple clinical studies have identified a temporal association between red blood cell (RBC) transfusions and necrotizing enterocolitis (NEC). With some variability, most of these studies indicate that up to one-third of all cases of NEC involving very low-birth weight infants may occur within 24-48h after receiving a RBC transfusion. There is also evidence that the risk of such transfusion-associated NEC may be higher in infants transfused with the greatest severity of anemia. In this article, we summarize the clinical evidence pertaining to these issues; specifically, the contribution of RBC transfusions, and the contribution of severity of underlying anemia, to the pathogenesis of a type of NEC potentially termed, "transfusion/anemia-associated NEC."

Slow enteral feeding decreases risk of transfusion associated necrotizing enterocolitis

BACKGROUND

Necrotizing Enterocolitis (NEC) is a multifactorial condition where PRBC transfusion is associated with necrotizing enterocolitis (TANEC) in about a third of all cases of NEC. We have investigated the role of feeding practices in incidence of TANEC. We sought to compare infants diagnosed with TANEC versus infants diagnosed with classic NEC and investigated the effects of a standardized slow enteral feeding (SSEF) protocol on TANEC incidence as well as the effects of SSEF on growth of infants with NEC.

METHODS

We conducted a retrospective cohort study, where medical records of infants born in a tertiary care neonatal intensive care unit (level IIIb) from January 1997 to May 2014 with birth weight < 1500 grams and gestational age≤34 weeks with NEC stage IIa or greater according to the modified Bell's staging were reviewed.

RESULTS

During the study period, 111 infants developed NEC, and 41/111 (37%) were diagnosed with TANEC. Infants with TANEC were smaller, more premature, had higher SNAPPE scores and were more anemic prior to transfusion compared with infants with 'classic NEC'. The severity of NEC did not differ between the two groups, however, infants with TANEC had worse outcomes and longer NICU stays. Introduction of SSEF protocol, led to a significant decrease in TANEC. There was no difference in weight and head circumference of infants in the two groups at 2 years corrected age.

CONCLUSION

SSEF led to a significant reduction in the incidence of TANEC without impairing growth at 2 years corrected age.

Red Blood Cell Transfusion in Preterm Infants: Current Evidence and Controversies

The current evidence regarding the indication, advantages and risks of red blood cell transfusion (RBCT) for preterm infants is discussed. This is an important area in Neonatology to be examined given that 90% of extremely low birth weight infants receive RBCT and many controversies remain regarding when to transfuse and the risks of RBCT. The various treatment thresholds and guidelines used are presented and we compare the short-term clinical benefits of liberal and restrictive RBCT in preterm infants; the majority of these are equivocal and sadly long-term outcome data is limited. The latest evidence on how anaemia and blood transfusion affect organ perfusion in preterm infants is presented. This is important when trying to establish the optimal trigger threshold for RBCT in preterm infants, especially because the knowledge about the adaptive physiological responses to anaemia in very low birth weight infants and the effects of RBCT at various levels of anaemia is also inadequate. Further research into the physiological adaptive response to anaemia of varying degrees and to RBCT at different levels of anaemia in preterm infants of different gestational and post-natal ages is needed before we can conclusively guide the optimal timing and trigger thresholds for RBCT in preterm infants.

Retrospective case-control study of necrotizing enterocolitis and packed red blood cell transfusions in very low birth weight infants

OBJECTIVE

The study objective was to explore the relationship between necrotizing enterocolitis (NEC) and packed red blood cell (pRBC) transfusion in very low birth weight (VLBW) neonates (<1500 g).

STUDY DESIGN

A six-year retrospective chart review of VLBW infants with NEC (Bell's Stage > II) and a pRBC transfusion within 48 hours of diagnosis. Prenatal data, postnatal course, transfusion history, and NEC outcomes were reviewed. The transfusion associated necrotizing enterocolitis (TANEC) cases were matched with controls (1:2) who were transfused but did not develop NEC as to proximity of birth date, gestational age, and receipt of transfusion.

RESULTS

Of 1139 VLBW admissions, there were 73 cases of NEC and 30 cases of TANEC (annual NEC rate 6.4%). TANEC cases were matched with 60 controls who were transfused but never developed NEC. Neonatal profiles were similar between all 3 groups, except for a higher proportion of infants <10th percentile in the non-TANEC group. Days of antibiotics and frequency of patient ductus arteriosus (PDA) ligation were lower in controls compared to NEC cases. Lower feeding rate at diagnosis of NEC/match were more common in control infants compared to TANEC infants. However, feeding abstinence rates were similar between the two groups. The number of transfusions prior to diagnosis/match was similar in all groups. There was no significant difference in pre-transfusion hematocrit values between the groups.

CONCLUSION

TANEC was common among NEC cases. PDA ligation was similar among TANEC and non-TANEC but lower in controls. Similar pre-transfusion hematocrits were found among TANEC and controls. Feeding abstinence rates were also similar between TANEC and controls.

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 darepoetin requires further study.

Plate Fixation Versus Intramedullary Nailing for Both-Bone Forearm Fractures: A Meta-analysis of Randomized Controlled Trials and Cohort Studies

OBJECTIVE

The aim of this study was to compare the radiographic and functional outcomes of operative intervention in patients with both-bone forearm fractures treated by open reduction and internal fixation (ORIF) with plates or intramedullary (IM) nailing.

METHODS

Studies published in PubMed, EMBASE, Web of Science, SinoMed (Chinese BioMedical Literature Service System, China), and CNKI (China National Knowledge Infrastructure, China) were systematically searched. The main outcomes included time to union, union rate, operation time, magnitude and location of radial bow, loss of forearm rotation, and complication rates. Results were expressed with weighted mean difference or risk ratio with 95 % confidence intervals. Pooled estimates were calculated using a fixed-effects or random-effects model according to the heterogeneity among studies.

RESULTS

A total of 13 studies met the inclusion criteria and were included in this meta-analysis. Compared with ORIF, IM nailing significantly reduced the operation time and complication rate. However, no significant differences were observed between the two surgical techniques in several outcomes, including time to union, union rate, radial bow magnitude, and loss of forearm rotation. Except in complications, these findings were consistent across the subgroup analysis of children and adult patients.

CONCLUSION

IM nailing is associated with shorter operation time and lower complication rate compared with ORIF. It is an effective and safe treatment option for children and adults with both forearm fractures. However, considering the limitations in this study, large-scale, high-quality randomized controlled trials are needed to indentify these findings.

Reducing Incidence of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a multifactorial disease that occurs when multiple risk factors and/or stressors overlap, leading to profound inflammation and intestinal injury. Due to its multifactorial nature, there has been much uncertainty in identifying clear strategies for prevention of NEC. Despite these obstacles, the incidence of NEC has gradually been decreasing over the past 10 years, in part due to quality improvement (QI) initiatives to prevent NEC. Current QI strategies primarily target the various predisposing conditions. This article reviews the evidence on which QI interventions to prevent NEC have been based and provides examples of successful QI interventions.

The relationship of red blood cell transfusion to intestinal mucosal injury in premature infants

OBJECTIVE

To determine the incidence of intestinal mucosal injury before and after transfusions in premature infants.

STUDY DESIGN

Urine was collected throughout the hospital stay of 62 premature infants and specimens obtained within 24h before and after transfusion were assayed for intestinal fatty acid binding protein (iFABP). A urinary iFABP:creatinine ratio (iFABP_u:Cr_u) of 2.0pg/nmol was considered elevated.

RESULT

Forty-nine infants were transfused. iFABPu:Cru was elevated following 71 (75.6%) of 94 transfusions for which urine was available. In 51 (71.8%) of these, iFABPu:Cru was also elevated prior to the transfusion. Among four cases of transfusion-associated NEC, iFABP_u was elevated following every sentinel transfusion and prior to three of them.

CONCLUSION

Subclinical intestinal mucosal injury is frequent following blood transfusions in premature infants and, when present, usually precedes transfusion. This suggests that transfusion may not be a primary mediator of intestinal injury so much as anemia and its associated conditions.

LEVEL OF EVIDENCE

Prognosis study/level 3.

Red Blood Cell Transfusion and Clinical Outcomes in Extremely Low Birth Weight Preterm Infants

BACKGROUND

Red blood cell (RBC) transfusion is often considered a life-saving measure in critically ill neonates. The smallest and least mature infants tend to receive the largest amount of transfusions. RBC transfusion itself has also been suggested as an independent risk factor of poor clinical outcome in critical patients. Our aim is to study if there are associations between RBC transfusion and in-hospital mortality, short-term morbidities, and late neurodevelopmental outcome in extremely low birth weight (ELBW) preterm infants.

METHODS

A cohort of ELBW preterm infants admitted to our neonatal intensive care unit from January 2009 to December 2010 were recruited. The number of RBC transfusions within 7 days, 30 days, and 60 days of life were recorded. Clinical outcomes including in-hospital mortality, development of retinopathy of prematurity (ROP), necrotizing enterocolitis, chronic lung disease, and later neurodevelopmental outcome were assessed with follow-up of up to 2 years of age. Multivariable logistic regression was used to estimate the associations between RBC transfusion and clinical outcomes.

RESULTS

A total of 98 ELBW preterm infants survived at the time of discharge. Of these survivors, the mean numbers of RBC transfusions were 2.5 ± 1.7, 7.4 ± 3.1, and 11.3 ± 4.5 times within 7 days, 30 days, and 60 days after birth, respectively. The number of transfusions within 7 days of life was correlated with risk of death before 1 month of age (odds ratio: 1.54, 95% confidence interval: 1.04-2.27, p = 0.03) and the number of transfusions within 30 days was correlated with risk of developing threshold ROP (odds ratio: 1.27, 95% confidence interval: 1.04-1.55, p = 0.02). The number of transfusions within 7 days of life was positively correlated with cognitive performance (Mental Developmental Index score) at 18-24 months of corrected age.

CONCLUSION

RBC transfusion has a negative impact on survival in ELBW infants. It increases the risk of developing ROP and affects late neurodevelopment. Decisions of blood transfusion in these very immature infants should be made cautiously taking these deleterious results into consideration.

Red blood cell transfusions can induce proinflammatory cytokines in preterm infants

BACKGROUND

The risk of developing red blood cell (RBC) transfusion-associated necrotizing enterocolitis (TANEC) in preterm infants has recently been emphasized. Our aim was to assess changes in cytokine serum levels after RBC transfusions in a cohort of very preterm infants to evaluate their possible proinflammatory effect.

STUDY DESIGN AND METHODS

We carried out a prospective observational study. One transfusion event was studied in infants less than 32 weeks' gestation and more than 7 days old (n = 20) admitted to a tertiary neonatal intensive care unit. Interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, interferon-γ (IFN-γ), IL-17, monocyte chemoattractant protein-1 (MCP-1), interferon-γ-induced protein 10 (IP-10), intracellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule serum levels were measured in enrolled patients within 120 minutes before (T₀ ) the RBC transfusion and then within 120 minutes (T₁ ), 12 ± 3 hours (T₂ ), 24 ± 6 hours (T₃ ), and 48 ± 6 hours (T₄ ) after the end of RBC transfusion.

RESULTS

Infants received 19.8 ± 3.0 mL of RBCs at the mean age of 50 ± 18 days. Their hematocrit level increased from 24.1 ± 1.2% to 39.4 ± 2.9%. IL-1β, IL-8, IFN-γ, IL-17, MCP-1, IP-10, and ICAM-1 increased significantly after RBC transfusions.

CONCLUSION

Proinflammatory cytokines are increased after RBC transfusion. These findings may contribute to explaining the pathogenesis of TANEC and suggest the opportunity of adopting wise transfusion guidelines that would help to avoid detrimental risks of transfusion-related immunomodulation and of undertransfusion.

Red blood cell transfusion in premature infants leads to worse necrotizing enterocolitis outcomes

BACKGROUND

Necrotizing enterocolitis (NEC) is a severe intestinal disease of premature infants with high mortality. Studies suggest a causative relationship between red blood cell (RBC) transfusion and NEC; however, whether RBC transfusion leads to worse outcomes in NEC is unknown. We sought to determine whether RBC transfusion was associated with an increased risk of surgical NEC and mortality.

METHODS

In this retrospective study, 115 patients were enrolled with NEC Bell's stage 2A or greater from 2010-2015. Patients were classified based on the timing of RBC transfusion before NEC: ≤72 h, >72 h, and no transfusion. Variables including gestational age (GA), birth weight (BW), feedings, and hematocrit levels were analyzed. Outcomes were surgical intervention for NEC following RBC transfusion and mortality.

RESULTS

Twenty-three (20%) infants developed NEC ≤ 72 h after RBC transfusion, 16 (69.6%) required surgery with a mortality rate of 21.7% (n = 5). Seventeen (15%) infants developed NEC > 72 h after RBC transfusion, 12 (70.6%) required surgery with a mortality rate of 23.5% (n = 4). 75 (65%) patients developed NEC without RBC transfusion, 17 (22.7%) required surgery with a mortality rate of 4% (n = 3). Lower GA and BW were significantly associated with RBC transfusion and the need for surgical intervention. RBC transfusion ≤72 h before NEC was associated with surgical NEC (pairwise adjusted P < 0.001) and mortality (pairwise adjusted P = 0.048). However, multivariable logistic regression analysis revealed RBC transfusion is not an independent risk factor for surgical NEC.

CONCLUSIONS

Infants of lower GA and BW were more likely to receive an RBC transfusion before NEC, which was significantly associated with surgical intervention and an increasing risk of mortality. Judicious use of transfusions in premature infants may improve NEC outcomes.

Pathogenesis of NEC: Impact of an altered intestinal microbiome

Necrotizing enterocolitis (NEC), a disease most commonly seen in preterm infants, often presents without warning and is associated with very high mortality and morbidity. Progress in the prevention and treatment of NEC has been slow. In this article, we will discuss some of the reasons as to why this progress has been slow. We will describe some of the factors that appear to be highly associated and important components in the pathophysiology of NEC. We will discuss the intestinal microbial environment of the fetus as well as the preterm infant and how interaction of dysbiosis with an immature gastrointestinal tract combined with dietary factors play a role in the pathogenesis of NEC. Testable hypotheses are discussed as well as how these may lead to not only a better understanding of the pathophysiology of the disease but also the preventative strategies.

Should we believe in transfusion-associated enterocolitis? Applying a GRADE to the literature

Numerous observational studies appear to demonstrate an association between packed red blood cell (pRBC) transfusions and necrotizing enterocolitis (NEC). However, the limited numbers of randomized controlled trials (RCTs) do not support a causal relationship between pRBC transfusion and NEC. We sought to determine the quality of the evidence behind transfusion-associated necrotizing enterocolitis (TANEC), and to formulate a GRADE-based recommendation regarding transfusion practices to reduce the risk of TANEC. A systematic search including MEDLINE, Embase, CINAHL, the Cochrane Central Register of Controlled Trials and clinical trials registries was performed for studies assessing the association between transfusion and NEC. Teams of two paired reviewers independently screened studies for eligibility, assessed risk of bias using the GRADE framework, and collected data from each eligible study. We examined studies for two time points following transfusion: within 48h if this was available, and otherwise at any time after transfusion. In total, 23 observational studies and three RCTs met inclusion criteria. The average rating for the quality of evidence of individual studies was between "very low" and "low." On pooling studies for GRADE review, we observed an inconsistency of results. This led to a final overall quality of "very low" for the evidence for an association between transfusions and necrotizing enterocolitis. The pooled outcome of NEC for observational/case control studies was an odds ratio of 1.13 (95% CI: 0.99-1.29) when TANEC was defined as occurring within 48 hours of transfusion. For NEC occurring at any time post-transfusion, the pooled OR was 1.95 (1.60-2.38). Conversely, the pooled outcome of NEC for the RCT data had an odds ratio of 0.6 (0.3, 1.21) with NEC being less frequent in the liberal transfusion group compared to the restrictive transfusion group. The overall quality of the evidence for TANEC is "very low," suggesting very little confidence in the effect estimate. RCT data tended toward apparent protection against NEC. The available evidence is not sufficient to support a practice recommendation around pRBC transfusions in the context of preventing the development of NEC.

Withholding feeding during transfusion: Standardization of practice and nutritional outcomes in premature infants

OBJECTIVE

To evaluate the nutritional impact of a feed-holding guideline during transfusion for infants <32 weeks gestation.

STUDY DESIGN

A pre-/post-interventional study was conducted after introduction of a guideline to hold feeds during transfusion. Demographic variables in addition to nutritional outcomes were collected on all infants admitted within 48 hours of birth with gestational age <32 weeks. Data was collected during a 6 month period pre-intervention and the 6 month period post-intervention.

RESULTS

There were 145 eligible infants. Mean birth weight and gestational age were similar in both periods. In total, 98 infants received transfusions, and 82 of those had an active feeding order prior to at least one transfusion. Total transfusions per infant and transfusions ordered while an infant had active feeding orders were similar in both periods. Time to full feedings was decreased post-intervention (p <  0.001). Weight at 34 weeks, incidence of second IV placement, additional IV fluid use, and hypoglycemia were similar between groups.Of 593 total transfusions, 207 were ordered while an infant had an active order for enteral nutrition. Pre-intervention, 64% of transfusions had feeds held during transfusion. Post-intervention, 87% of transfusions had feeds held during transfusion. Feeds were held more often (p <  0.001) and for a shorter duration (p = 0.005) in the post-intervention group.

CONCLUSION

Implementing a guideline standardizing feeding practices during transfusions in premature infants increases standardization of care and results in decreased variability in practice. Adverse nutritional consequences were not found after the introduction of the routine practice of holding feedings during transfusion in preterm infants.

Blood transfusion in preterm infants improves intestinal tissue oxygenation without alteration in blood flow

BACKGROUND AND OBJECTIVE

The objective of the study was to investigate the splanchnic blood flow velocity and oximetry response to blood transfusion in preterm infants according to postnatal age.

MATERIALS AND METHODS

Preterm infants receiving blood transfusion were recruited to three groups: 1-7 (group 1; n = 20), 8-28 (group 2; n = 21) and ≥29 days of life (group 3; n = 18). Superior mesenteric artery (SMA) peak systolic (PSV) and diastolic velocities were measured 30-60 min pre- and post-transfusion using Doppler ultrasound scan. Splanchnic tissue haemoglobin index (sTHI), tissue oxygenation index (sTOI) and fractional tissue oxygen extraction (sFTOE) were measured from 15-20 min before to post-transfusion using near-infrared spectroscopy.

RESULTS

The mean pretransfusion Hb in group 1, 2 and 3 was 11, 10 and 9 g/dl, respectively. The mean (SD) pretransfusion SMA PSV in group 1, 2 and 3 was 0·63 (0·32), 0·81 (0·33) and 0·97 (0·40) m/s, respectively, and this did not change significantly following transfusion. The mean (SD) pretransfusion sTOI in group 1, 2 and 3 was 36·7 (19·3), 44·6 (10·4) and 41·3 (10·4)%, respectively. The sTHI and sTOI increased (P < 0·01), and sFTOE decreased (P < 0·01) following transfusion in all groups. On multivariate analysis, changes in SMA PSV and sTOI following blood transfusion were not associated with PDA, feeding, pretransfusion Hb and mean blood pressure.

CONCLUSION

Pretransfusion baseline splanchnic tissue oximetry and blood flow velocity varied with postnatal age. Blood transfusion improved intestinal tissue oxygenation without altering mesenteric blood flow velocity irrespective of postnatal ages.

Barriers to Knowledge Translation Regarding the Use of Probiotics as a Risk-Reduction Strategy for Necrotizing Enterocolitis

BACKGROUND

Increasingly, evidence supports enteral probiotics are an important risk-reduction strategy for necrotizing enterocolitis (NEC) among very low birth-weight and extremely low birth-weight preterm infants. Yet, the majority of providers remain reluctant to implement practice changes.

PURPOSE

The aim of this study was to better understand the discrepancy between the available evidence and clinical practice regarding the use of probiotics and other NEC prevention strategies in New Jersey.

METHODS

Using an exploratory descriptive design, a multimodal interprofessional survey was developed and executed to elicit intensive care nursery provider knowledge, views, and current practice.

RESULTS

Although the sample size was small (N = 29), approximately one-half of respondents familiar with the literature rated the quality of the evidence regarding probiotics as "above average" to "excellent." These respondents were "very likely" to "extremely likely" to recommend probiotics as an NEC prevention strategy; however, none actually prescribed this intervention. The most important reason respondents did not prescribe probiotics was the focus on providing exclusive maternal and donor breast milk feedings. Other confounding factors included provision of oral colostrum care, standardized feeding protocols, and withholding feedings during blood transfusion.

IMPLICATIONS FOR PRACTICE

Study results suggested that some providers (primarily nurses) were not familiar with probiotic literature, which may contribute to deficits in knowledge translation to practice.

IMPLICATIONS FOR RESEARCH

Areas for future study include identifying improved mechanisms for knowledge dissemination, recognizing and addressing barriers and facilitators to knowledge translation, and understanding how probiotics fit and/or contrast with other NEC risk-reduction strategies in the research and clinical settings.

Etiology and medical management of NEC

Necrotising enterocolitis (NEC) is a serious infection of the bowel that predominantly affects preterm infants and is a leading cause for mortality and morbidity in preterm infants. It involves a spectrum of pathology including widespread inflammation of the intestinal mucosa, invasion of the immature gut by enteric gas forming bacteria, dissection of the gut wall and portal veins by this gas, often culminating in ischemic necrosis of the intestine. This article provides an overview of the incidence, etio-pathological risk factors, preventive strategies and medical management of NEC.

Blood transfusions, increased rates of surgical NEC, and lower survival: a propensity score-matched analysis

PURPOSE

We sought to investigate the association between blood transfusions (BT), rates of necrotizing enterocolitis requiring surgical intervention (SNEC), and survival.

METHODS

Blood transfusions in premature infants were identified in the Kids' Inpatient Database (2003-2009). Propensity score-matched analysis compared SNEC outcomes in BT vs. non-BT groups. Multivariate analyses were performed to determine independent predictors of outcome.

RESULTS

Overall, 663740 cases were identified and 4.9% received BT. Surgical necrotizing enterocolitis occurred in 493 cases in the BT group, while SNEC occurred in 1049 cases in the non-BT group. Propensity score analysis of 20991 BT and 20988 non-BT cases demonstrated higher SNEC rates with BT (odds ratio [OR], 1.21) vs non-BT. Surgical necrotizing enterocolitis with BT had lower survival rates (58%) vs non-BT (67%). Surgical necrotizing enterocolitis with BT had lower length of stay and total charges vs non-BT. On multivariate analyses, SNEC mortality with BT increased for lower gestational age, males (OR, 45.7), African Americans (OR, 64.4), and infants with cardiac anomalies (OR, 50.8) or bronchopulmonary dysplasia (OR, 177). Non-BT SNEC demonstrated higher mortality with lower gestational age and infants with bronchopulmonary dysplasia (OR, 6.56) or sepsis (OR, 3.66).

CONCLUSION

On propensity score-matched analysis, SNEC occurs at higher rates after BT and is associated with lower survival and lower resource utilization vs SNEC without BT.

Quality Improvement Initiative to Reduce the Necrotizing Enterocolitis Rate in Premature Infants

OBJECTIVE

To reduce the incidence of necrotizing enterocolitis (NEC) among very low birth weight (VLBW) infants admitted to 8 intensive care nurseries from a 2010 baseline of 8.0% to <4.0% by 2012 and sustain for 6 months using quality improvement (QI) methodology.

METHODS

A multidisciplinary NEC QI team used the Vermont Oxford Network definition of NEC and the Institute for Healthcare Improvement model. The specific aims were evidenced based and included (1) standardized early human milk feedings, (2) conservative feeding guidelines during blood transfusions and indomethacin treatment, and (3) restriction of ranitidine use in VLBW infants. Inclusion criteria included VLBW infants admitted within the study period without NEC. Exclusion criteria included established NEC or spontaneous intestinal perforation unrelated to NEC. The incidence of NEC and NEC-related surgery were tracked using statistical process control methodology.

RESULTS

The baseline NEC rate in 2010 was 8% (27 NEC cases in 335 VLBW infants). After initiation of early human-milk feeding and conservative feeds during blood transfusions guidelines in November 2011, only 3.1% (19 of 606 VLBW infants) had developed NEC through December 2013 (P = .001). Special cause variation was noted in June 2012 establishing a new centerline at 3.1%. NEC-related mortality decreased from a 2010 baseline mean of 2.7% to a new baseline mean of 0.9% from January 2011 to December 2013.

CONCLUSIONS

Implementation of QI initiatives decreased the NEC rate from 8.0% to <4.0%. Early human milk feedings and conservative feeding during blood transfusion policies appear to have significant impact on NEC reduction.

CONTRIBUTING FACTORS FOR DEVELOPMENT OF NECROTIZING ENTEROCOLITIS IN PRETERM INFANTS IN THE NEONATAL INTENSIVE CARE UNIT

BACKGROUND

necrotizing enterocolitis is a serious condition that affects mostly preterm infants, with high mortality rate.

AIM

to estimate the influence of potentially contributing factors of this multifactorial disease.

METHODS

the study group included 51 necrotizing enterocolitis infants who were less than 37 week gestation who were hospitalized in NICU during a five year period. The control group consisted of 71 patients with approximately the same gestational age and birth weight. Average gestational age in the study group was 30.2 weeks (SD 3.7), average birth weight 1502g (SD 781.5). Average postnatal age in the time of the presenting NEC was 18.2 days (SD 12.8).

RESULTS

Logistic regression estimates the influence of risk factors, which in our study related to the treatment of preterm infants on the likelihood of NEC development. Our regression model consisted of seven independent variables (nosocomial infections, mechanical ventilation, nasal continuous positive pressure, morphine, inotropes, blood transfusions, and H2 blockers), which were shown to have a statistically significant impact, X2 (7, n=1222) = 49.522, p<0.0001; two independent variables (nosocomial infection and H2 blockers use) were statistically significant. Preterm infants with nosocomial infection had a three times greater chance of developing NEC, and infants who received H2 blockers had a 1.5 higher risk.

CONCLUSIONS

Underlying pathology of very low birth weight infants and their treatment in NICU contribute to NEC development. Identifying risk factors can be crucial for the early diagnosis and outcome of disease. Awareness of risk factors should influence changes in practice to reduce the risk of NEC.

Red blood cell transfusions increase fecal calprotectin levels in premature infants

OBJECTIVE

We hypothesized that red blood cell (RBC) transfusions influence intestinal inflammation in very low birth weight (VLBW) infants. We also suspected that hematocrit (Hct) at transfusions and RBC storage time correlate with intestinal inflammation.

STUDY DESIGN

VLBW infants, without major congenital defects, intestinal perforation or necrotizing enterocolitis, were enrolled prospectively. Fecal calprotectin (FC) levels were measured from stool samples collected before and after RBC transfusions. Data on Hct and RBC storage time were collected.

RESULT

Data from 42 RBC transfusions given to 26 infants revealed that FC levels increased faster than baseline after RBC transfusions (P=0.018) and were higher in multiple-transfused infants (0 to 48 and >48 h post transfusion, P=0.007 and P=0.005, respectively). Lower Hct and RBC storage >21 days correlated with higher FC levels (P=0.044 and P=0.013, respectively).

CONCLUSION

RBC transfusions, anemia and prolonged RBC storage were associated with an increase in intestinal inflammation.

Neonatal Transfusion Medicine: Five Major Unanswered Research Questions for the Twenty-First Century

Blood component transfusions are important to the care of preterm neonates; however, their use in clinical practice often is not based on high levels of evidence. Five major questions for neonates are discussed: (1) What is the optimal red blood cell (RBC) transfusion threshold? (2) What is the optimal platelet transfusion threshold? (3) Does the storage age of an RBC unit affect outcomes? (4) Does RBC transfusion contribute to the pathogenesis of necrotizing enterocolitis? and (5) Which new practices should be used to prevent transfusion-transmitted infections? Although definitive answers to these questions do not exist, future research should help answer them.

Variability in splanchnic tissue oxygenation during preterm red blood cell transfusion given for symptomatic anaemia may reveal a potential mechanism of transfusion-related acute gut injury

BACKGROUND

There is increasing evidence indicating an association between red blood cell (RBC) transfusions and necrotising enterocolitis (NEC) in preterm infants, especially late-onset NEC. This phenomenon is referred to as transfusion-related acute gut injury (TRAGI). One theory as to a pathophysiological mechanism is that transfusion may result in an ischemia-reperfusion injury to intestinal tissue. We tested the hypothesis that there is significantly greater variability during transfusion in splanchnic tissue oxygen saturation (SrSO2) than in cerebral tissue oxygen saturation (CrSO2).

MATERIALS AND METHODS

This was a prospective, observational study using near-infrared spectroscopy to monitor SrSO2 and CrSO2 in preterm neonates undergoing RBC transfusion for symptomatic anaemia. Mean, standard deviation, highest and lowest SrSO2 and CrSO2 values during each transfusion were determined. The greatest difference in SrSO2 and CrSO2 during each transfusion was calculated, along with the coefficient of variation.

RESULTS

We studied 37 subjects. Throughout all transfusions, the mean SrSO2 was 45.6% ±13.8 and the mean CrSO2 was 65.4% ±6.9 (p<0.001). The variability of SrSO2 was significantly greater than that of CrSO2. Averaging data from all subjects, the greatest difference in SrSO2 was 43.8% ±13.4 compared with 23.3% ±7.6 for CrSO2 (p<0.001). The mean coefficient of variation in all transfusions was 20.5% for SrSO2 and 6.0% for CrSO2 (p<0.001). Increasing post-conceptional age did not affect SrSO2 variability (R(2) =0.022; p=0.379), whereas CrSO2 variability during transfusion decreased with increasing post-conceptional age (R(2)=0.209; p=0.004).

DISCUSSION

In preterm infants, there is a large degree of tissue oxygenation variability in splanchnic tissue during RBC transfusion and this does not change with increasing maturity. We speculate that these findings, combined with lower average tissue oxygenation, may demonstrate susceptibility of the preterm gut to TRAGI.

Decreased hazard of necrotizing enterocolitis in preterm neonates receiving red cell transfusions

BACKGROUND AND OBJECTIVES

Many observational studies reporting a temporal association between red cell transfusions (RBCTs) and necrotizing enterocolitis (NEC) in preterm infants fail to take into account RBCTs in infants without NEC. The objective of this study was to investigate the association between RBCTs and NEC in an analytical retrospective cohort study with minimization of selection and measurement bias and controlling for clinical covariates.

METHODS

Inborn preterm infants [23-32 weeks gestational age (GA)] without major congenital anomalies were eligible. Association of RBCT and modified Bell's Stage ≥2A NEC was explored using bivariate analyses and verified using multivariable Cox regression.

RESULTS

Of 627 eligible infants, 305 neither received RBCT nor developed NEC and 12 developed NEC prior to RBCT. Of 310 infants with RBCT, 27 developed NEC. Compared to infants without NEC, infants with NEC received significantly lower number of RBCTs before diagnosis of NEC (p = 0.000). On multivariable Cox regression controlling for clinical covariates, dichotomous RBCT exposure was associated with 60% reduced hazard for NEC.

CONCLUSIONS

RBCT exposure was associated with decreased hazards for NEC in preterm infants in this study; factors previously reported to be associated with NEC remained statistically significant predictors.

How is national recipient hemovigilance conducted in the United States?

A national recipient hemovigilance system was introduced in the United States in 2010, when voluntary enrollment began as part of the National Healthcare Safety Network (NHSN) Hemovigilance Module. NHSN is a secure, Web-based surveillance system operated by the Centers for Disease Control and Prevention and used by US health care facilities to report a variety of patient safety information. The Hemovigilance Module is used for comprehensive monitoring of transfusion-related adverse events. Participating facilities can utilize analytic tools available within the module to identify opportunities for enhancing transfusion safety, evaluate the effectiveness of interventions, and compare facility specific transfusion-related data to aggregate national estimates. Data may be voluntarily shared by facilities with external partners for patient safety improvement initiatives and to fulfill reporting mandates. We describe the key characteristics of the Hemovigilance Module, highlight the benefits for participating facilities, and discuss the use of reported data for establishing national estimates of transfusion-associated adverse events to identify gaps in transfusion safety and opportunities for interventions. National hemovigilance systems are essential to recognize gaps in transfusion safety and identify opportunities for interventions to improve patient safety and outcomes.

Monitoring mesenteric tissue oxygenation with near-infrared spectroscopy during packed red blood cell transfusion in preterm infants

OBJECTIVE

To monitor altered mesenteric tissue oxygen saturation (StO2) before and after blood transfusion.

METHODS

We placed a 4-wavelength NIRS sensor (FORE-SIGHT, CASMED, Branford, CT USA) on the right lower abdominal quadrant prior to transfusion and measured StO2 for up to 48 hours post transfusion. Pulse oximetry (SpO2) data was collected simultaneously, with fractional tissue oxygen extraction (FTOE) and the [SpO2-StO2] difference calculated to normalize for hypoxic episodes. All data was combined and averaged in 30 minute windows for events before, during, and post transfusion to determine long term trends and analyzed using Repeated Measures ANOVA. 24 infants were enrolled in this study with 36 hours of data collected for 23 subjects and 48 hours for 16 subjects.

RESULTS

We found no significant differences in any of the parameters when compared pre and post transfusion values at 3, 6, 12, 24 and 36 hours post transfusion. For the 16 subjects monitored to 48 hours, there was a significant decrease in FTOE and near significant increase in StO2 and reciprocal decrease in [SpO2 - StO2] at 48 hours post transfusion.

CONCLUSIONS

There are several plausible mechanisms that may explain the relationship between necrotizing enterocolitis and PRBC transfusion; however, mesenteric tissue oxygen saturation changes did not clearly show that ischemia or re-perfusion injury to be one of the potential mechanisms.

Allogeneic umbilical cord blood red cell concentrates: an innovative blood product for transfusion therapy of preterm infants

BACKGROUND

Preterm infants often receive blood transfusions early in life. In this setting, umbilical cord blood (UCB) might be safer than adult blood (A) with respect to infectious and immunologic threats.

OBJECTIVES

To evaluate, as a first objective, the feasibility of fulfilling transfusion needs of preterm infants with allogeneic UCB red blood cell (RBC) concentrates and, as a secondary objective, to assess the safety of allogeneic cord blood transfusions.

METHODS

At the Neonatal Intensive Care Unit and the UNICATT Cord Blood Bank of 'A. Gemelli' Hospital in Rome, a prospective study was carried out over a 1-year period, enrolling newborns with gestational age ≤30 weeks and/or birth weight ≤1,500 g requiring RBC transfusions within the first 28 days of life. At first transfusion, patients were assigned to receive UCB-RBCs or A-RBCs depending on the availability of ABO-Rh(D)-matched UCB-RBC units. The same regimen (UCB-RBC or A-RBC units) was thereafter maintained, unless ABO-Rh(D)-matched UCB-RBC units were not available.

RESULTS

Overall, 23 UCB-RBC units were transfused to 9 patients; the requests for UCB-RBC units were met in 45% of patients at the first transfusion and in 78% at the subsequent transfusions. At a median follow-up of 57 days (range 6-219), no acute or delayed transfusion-related adverse events occurred. Hematocrit gain after transfusion and time intervals between transfusions were similar in the UCB-RBC and A-RBC group, as well.

CONCLUSIONS

Transfusing allogeneic UCB-RBC units in preterm infants appears a feasible and safe approach, although the transfusion needs of our study population were not completely covered. More data are necessary to validate this novel transfusion practice.

Packed red blood cell transfusion is not associated with increased risk of necrotizing enterocolitis in premature infants

OBJECTIVE

Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC.

STUDY DESIGN

We used a case-control design to match each case of NEC in our study population of infants born at<33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth.

RESULT

The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11).

CONCLUSION

In contrast to previous studies, our case-control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC.

One size will never fit all: the future of research in pediatric transfusion medicine

There is concern at the National Heart, Lung, and Blood Institute (NHLBI) and among transfusion medicine specialists regarding the small number of investigators and studies in the field of pediatric transfusion medicine (PTM). Accordingly, the objective of this article is to provide a snapshot of the clinical and translational PTM research considered to be of high priority by pediatricians, neonatologists, and transfusion medicine specialists. Included is a targeted review of three research areas of importance: (i) transfusion strategies, (ii) short- and long-term clinical consequences, and (iii) transfusion-transmitted infectious diseases. The recommendations by PTM and transfusion medicine specialists represent opportunities and innovative strategies to execute translational research, observational studies, and clinical trials of high relevance to PTM. With the explosion of new biomedical knowledge and increasingly sophisticated methodologies over the past decade, this is an exciting time to consider transfusion medicine as a paradigm for addressing questions related to fields such as cell biology, immunology, neurodevelopment, outcomes research, and many others. Increased awareness of PTM as an important, fertile field and the promotion of accompanying opportunities will help establish PTM as a viable career option and advance basic and clinical investigation to improve the health and wellbeing of children.

Reducing necrotizing enterocolitis in very low birth weight infants using quality-improvement methods

OBJECTIVE

Owing to a rise in necrotizing enterocolitis (NEC, stage ⩾ 2) among very low birth weight (VLBW, birth weight <1500 g) infants from 4% in 2005 to 2006 to 10% in 2007 to 2008, we developed and implemented quality improvement (QI) initiatives. The objective was to evaluate the impact of QI initiatives on NEC incidence in VLBW infants.

STUDY DESIGN

In September 2009, we developed an NEC QI multidisciplinary team that conducted literature reviews and reviewed practices from other institutions to develop a feeding protocol, which was implemented in December 2009. The team tracked intervention compliance and occurrence of NEC stage ⩾ 2. In May 2010, we reviewed our nasogastric tube practice and relevant literature to develop a second intervention that reduced nasogastric tube indwelling time. The infants were divided into three groups: baseline (January 2008 to Novovember 2009, n219), QI phase 1 (December 2009 to May 2010, n62) and QI phase 2 (June 2010 to November 2011, n170).

RESULT

The NEC incidence did not decrease after implementation of the feeding protocol in QI phase 1 (19.4%) but did decline significantly after changing nasogastric tube management in QI phase 2 (2.9%). Multivariable logistic regression analysis demonstrated a significant relationship between QI phase and the incidence of NEC.

CONCLUSION

QI initiatives were effective in decreasing NEC incidence in our high human milk-feeding NICU. Nasogastric tube bacterial contamination may have contributed to our peak in NEC incidence.

Effect of umbilical cord milking on morbidity and survival in extremely low gestational age neonates

OBJECTIVE

Delayed umbilical cord clamping benefits extremely low gestational age neonates (ELGANs) but has not gained wide acceptance. We hypothesized that milking the umbilical cord (MUC) would avoid resuscitation delay but improve hemodynamic stability and reduce rates for composite outcome of severe intraventricular hemorrhage, necrotizing enterocolitis, and/or death before discharge.

STUDY DESIGN

We implemented a joint neonatal/maternal-fetal quality improvement process for MUC starting September 2011. The MUC protocol specified that infants who were born at <30 weeks of gestation undergo MUC 3 times over a duration of <30 seconds at delivery. Obstetric and neonatal data were collected until discharge. We compared the MUC group to retrospective ELGAN cohort delivered at our center between January 2010 and August 2011. Analysis was intention-to-treat.

RESULTS

We identified 318 ELGANs: 158 eligible for MUC and 160 retrospective control neonates. No adverse events were reported with cord milking. There was no difference in neonatal resuscitation, Apgar scores, or admission temperature. Hemodynamic stability was improved in the MUC group with higher mean blood pressures through 24 hours of age, despite less vasopressor use (18% vs 32%; P < .01). The initial hematocrit value was higher (50% vs 45%; P < .01), and red cell transfusions were fewer (57% vs 79%; P < .01) in MUC vs control infants. Presence of the composite outcome was significantly less in MUC vs the historic control infants (22% v 39%; odds ratio, 1.81; 95% confidence interval, 1.06-3.10). There were also reductions in intraventricular hemorrhage, necrotizing enterocolitis, and death before hospital discharge.

CONCLUSION

MUC improves early hemodynamic stability and is associated with lower rates of serious morbidity and death among ELGANs.

Can a national dataset generate a nomogram for necrotizing enterocolitis onset?

OBJECTIVE

Mother's own milk and donor human milk use is increasing as a means of necrotizing enterocolitis (NEC) prevention. Early onset of enteral feeding has been associated with improvement of many outcomes but has not been shown to reduce the incidence of NEC. Better definition of the window of risk for NEC by gestational strata should improve resource management with respect to donor human milk and enhance our understanding of NEC timing and pathogenesis. Our objective was to establish a NEC dataset of sufficient size and quality, then build a generalizable model of NEC onset from the dataset across gestational strata.

STUDY DESIGN

We used de-identified data from the Pediatrix national dataset and filtered out all diagnostic confounders that could be identified by either specific diagnoses or logical exclusions (example dual diagnoses), with a specific focus on NEC and spontaneous intestinal perforation (SIP) as the outcomes of interest. The median day of onset was plotted against the gestational age for each of these diagnoses and analyzed for similarities and differences in the day of diagnosis.

RESULT

Onset time of medical NEC was inversely proportional to gestation in a linear relationship across all gestational ages. We found the medical NEC dataset displayed characteristics most consistent with a homogeneous disease entity, whereas there was a skew towards early presentation in the youngest gestation groups of surgical NEC (suggesting probable SIP contamination).

CONCLUSION

Our national dataset demonstrates that NEC onset occurs in an inverse stereotypic, linear relationship with gestational age at birth. Medical NEC is the most reliable sub-cohort for the purpose of determining the temporal window of NEC risk.

Red blood cell transfusion is not associated with necrotizing enterocolitis: a review of consecutive transfusions in a tertiary neonatal intensive care unit

OBJECTIVE

To explore the association between red blood cell transfusion and necrotizing enterocolitis (NEC) in a neonatal intensive care unit with liberal transfusion practices.

STUDY DESIGN

A retrospective cohort study was conducted for all infants weighing <1500 g who received at least 1 packed red blood cell transfusion between January 2008 and June 2013 in a tertiary neonatal intensive care unit. The primary outcome was NEC, defined as Bell stage II or greater. The temporal association of NEC and transfusion was assessed using multivariate Poisson regression.

RESULTS

The study sample included 414 very low birth weight infants who received 2889 consecutive red blood cell transfusions. Twenty-four infants (5.8%) developed NEC. Four cases of NEC occurred within 48 hours of a previous transfusion event. Using multivariate Poisson regression, we did not find evidence of a temporal association between NEC and transfusion (P = .32).

CONCLUSION

There was no association between NEC and red blood cell transfusion. Our results differ from previous studies and suggest that the association between NEC and transfusion may be contextual.

Feeding preterm infants during red blood cell transfusion is associated with a decline in postprandial mesenteric oxygenation

OBJECTIVE

To evaluate the mesenteric tissue oxygenation response in preterm infants fed and not fed during red blood cell (RBC) transfusions.

STUDY DESIGN

Prospective, observational comparison of mesenteric oxygenation using near-infrared spectroscopy in preterm infants (<33 weeks' at birth) who were fed or not fed during RBC transfusion. Tissue oxygenation means were examined up to 48 hours after each transfusion event.

RESULTS

Mean mesenteric regional oxygen saturation (rSO2) slopes during RBC transfusion of fed (n = 9) vs not fed (n = 8) infants ranged from -0.23 to +0.23 (mean 0.04) with no differences between groups (P = .480). However, following transfusions, postprandial mesenteric oxygenation means significantly declined in infants fed during transfusion compared with infants not fed during transfusion (P < .001). Infants fed during RBC transfusion had a mean 2.16 point decrease in rSO2 mesenteric oxygenation with each sequential feeding post-transfusion, whereas infants not fed during RBC transfusion increased their rSO2 postprandial mesenteric oxygenation by a mean of 2.09 points.

CONCLUSIONS

Mesenteric tissue oxygenation during RBC transfusion is not influenced by feeding status. However, infants fed during RBC transfusion had, for the next 15 hours, decreasing postprandial mesenteric tissue oxygenation patterns compared with infants not fed during RBC transfusion. Feeding during RBC transfusions may increase the risk for mesenteric ischemia and the development of transfusion-related necrotizing enterocolitis in preterm infants.