Umbilical cord milking reduces need for red cell transfusions and improves neonatal adaptation in preterm infants: Meta-analysis

Umbilical cord milking-benefits and risks

The most common methods for providing additional placental blood to a newborn are delayed cord clamping (DCC) and umbilical cord milking (UCM). However, DCC carries the potential risk of hypothermia due to extended exposure to the cold environment in the operating room or delivery room, as well as a delay in performing resuscitation. As an alternative, umbilical cord milking (UCM) and delayed cord clamping with resuscitation (DCC-R) have been studied, as they allow for immediate resuscitation after birth. Given the relative ease of performing UCM compared to DCC-R, UCM is being strongly considered as a practical option in non-vigorous term and near-term neonates, as well as preterm neonates requiring immediate respiratory support. However, the safety profile of UCM, particularly in premature newborns, remains a concern. This review will highlight the currently known benefits and risks of umbilical cord milking and explore ongoing studies.

Umbilical Cord Management in Late Preterm and Term Infants: A Randomized Controlled Trial

OBJECTIVE

The study aimed to compare the effects of three different methods of umbilical cord management on hematological parameters in term and late-preterm infants.

STUDY DESIGN

A randomized controlled trial comparing intact-umbilical cord milking (I-UCM) with cut-umbilical cord milking (C-UCM) and immediate cord clamping (ICC) in neonates born >35 weeks' gestation.

RESULTS

A total of 587 infants were evaluated. Of these, 197 were assigned to I-UCM, 190 to C-UCM, and 200 to ICC. Mean hemoglobin and hematocrit levels at 48 hours of age were higher in I-UCM group compared with the ICC group (p = 0.002 and p = 0.010, respectively).

CONCLUSION

These findings suggest that I-UCM is more beneficial choice. Further trials are needed to assess the various long- and short-term effects of different cord milking methods.

KEY POINTS

· This is the first study comparing these three methods (I-UCM, C-UCM, and ICC) concurrently.. · I-UCM is more beneficial choice.. · Although the terms I-UCM and C-UCM are often used interchangeably, these are different procedures..

Perinatal care for the extremely preterm infant

Being born preterm (prior to 37 weeks of completed gestation) is a leading cause of childhood death up to five years of age, and is responsible for the demise of around one million preterm infants each year. Rates of prematurity, which range from approximately 5 to 18% of births, are increasing in most countries. Babies born extremely preterm (less than 28 weeks' gestation) and in particular, in the periviable (20^0/7-25^6/7 weeks) period, are at the highest risk of death, or the development of long-term disabilities. The perinatal care of extremely preterm infants and their mothers raises a number of clinical, technical, and ethical challenges. Focusing on 'micropremmies', or those born in the periviable period, this paper provides an update regarding the aetiology and impacts of periviable preterm birth, advances in the antenatal, intrapartum, and acute post-natal management of these infants, and a review of counselling/support approaches for engaging with the infant's family. It concludes with an overview of emerging technology that may assist in improving outcomes for this at-risk population.

Short-term efficacy of umbilical cord milking in preterm infants: systematic review and meta-analysis

BACKGROUND

To systematically evaluate short-term efficacy of UCM versus other interventions in preterm infants.

METHODS

Six engines were searched until February 2020 for randomized controlled trials (RCTs) assessing UCM versus immediate cord clamping (ICC), delayed cord clamping (DCC), or no intervention. Primary outcomes were overall mortality, intraventricular hemorrhage (IVH), and patent ductus arteriosus (PDA); secondary outcomes were need for blood transfusion, mean blood pressure (MBP), serum hemoglobin (Hb), and ferritin levels. Random-effects meta-analyses were used.

RESULTS

Fourteen RCTs (n = 1708) were included. In comparison to ICC, UCM did not decrease mortality (RR 0.5, 95% CI 0.2-1.1), IVH (RR 0.7, 95% CI 0.5-1.0), or PDA (RR 1.0, 95% CI 0.7-1.5). However, UCM reduced need of blood transfusion (RR 0.5, 95% CI 0.3-0.9) and increased MBP (MD 2.5 mm Hg, 95% CI 0.5-4.5), Hb (MD 1.2 g/dL, 95% CI 0.8-1.6), and ferritin (MD 151.4 ng/dL, 95% CI 59.5-243.3). In comparison to DCC, UCM did not reduce mortality, IVH, PDA, or need of blood transfusion but increased MBP (MD 3.7, 95% CI 0.6-6.9) and Hb (MD 0.3, 95% CI -0.2-0.8). Only two RCTs had high risk of bias.

CONCLUSIONS

UCM did not decrease short-term clinical outcomes in comparison to ICC or DCC in preterm infants. Intermediate outcomes improved significantly with UCM.

IMPACT

In 14 randomized controlled trials (RCTs), umbilical cord milking (UCM) did not reduce mortality, intraventricular hemorrhage, or patent ductus arteriosus compared to immediate (ICC) or delayed cord clamping (DCC). UCM improved mean blood pressure and hemoglobin levels compared to ICC or DCC. In comparison to ICC, UCM reduced the need for blood transfusion. We updated searches until February 2020, stratified by type of control, and performed subgroup analyses. There was low quality of evidence about clinical efficacy of UCM. Most of RCTs had low risk of bias. UCM cannot be recommended as standard of care for preterm infants.

Umbilical cord milking in preterm infants: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of the efficacy and safety of umbilical cord milking in preterm infants.

DESIGN

Randomised controlled trials comparing umbilical cord milking with delayed cord clamping/immediate cord clamping in preterm infants were identified by searching databases, clinical trial registries and reference list of relevant studies in November 2019. Fixed effects model was used to pool the data on various clinically relevant outcomes.

MAIN OUTCOME MEASURES

Mortality and morbidities in preterm neonates.

RESULTS

Nineteen studies (2014 preterm infants) were included. Five studies (n=922) compared cord milking with delayed cord clamping, whereas 14 studies (n=1092) compared milking with immediate cord clamping. Cord milking, as opposed to delayed cord clamping, significantly increased the risk of intraventricular haemorrhage (grade III or more) (risk ratio (RR): 1.95 (95% CI 1.01 to 3.76), p=0.05). When compared with immediate cord clamping, cord milking reduced the need for packed RBC transfusions (RR:0.56 (95% CI 0.43 to 0.73), p<0.001). There was limited information on long-term neurodevelopmental outcomes. The grade of evidence was moderate or low for the various outcomes analysed.

CONCLUSION

Umbilical cord milking, when compared with delayed cord clamping, significantly increased the risk of severe intraventricular haemorrhage in preterm infants, especially at lower gestational ages. Cord milking, when compared with immediate cord clamping, reduced the need for packed RBC transfusions but did not improve clinical outcomes. Hence, cord milking cannot be considered as placental transfusion strategy in preterm infants based on the currently available evidence.

The Impact of Nutrition-Specific and Nutrition-Sensitive Interventions on Hemoglobin Concentrations and Anemia: A Meta-review of Systematic Reviews

Anemia is a multifactorial condition arising from inadequate nutrition, infection, chronic disease, and genetic-related etiologies. Our aim was to assess the impact of nutrition-sensitive and nutrition-specific interventions on hemoglobin (Hb) concentrations and anemia to inform the prioritization and scale-up of interventions to address the multiple causes of anemia. We performed a meta-review synthesis of information by searching multiple databases for reviews published between 1990 and 2017 and used standard methods for conducting a meta-review of reviews, including double independent screening, extraction, and quality assessment. Quantitative pooling and narrative syntheses were used to summarize information. Hb concentration and anemia outcomes were pooled in specific population groups (children aged <5 y, school-age children, and pregnant women). Methodological quality of the systematic reviews was assessed using Assessing the Methodological Quality of Systematic Reviews (AMSTAR) criteria. Of the 15,444 records screened, we identified 118 systematic reviews that met inclusion criteria. Reviews focused on nutrition-specific interventions (96%). Daily and intermittent iron supplementation, micronutrient powders, malaria treatment, use of insecticide-treated nets (ITNs), and delayed cord clamping were associated with increased Hb concentration in children aged <5 y. Among children older than 5 y, daily and intermittent iron supplementation and deworming, and in pregnant women, daily iron-folic acid supplementation, use of ITNs, and delayed cord clamping, were associated with increased Hb concentration. Similar results were obtained for the reduced risk of anemia outcome. This meta-review suggests the importance of nutrition-specific interventions for anemia and highlights the lack of evidence to understand the influence of nutrition-sensitive and multifaceted interventions on the condition.

Grading the evidence to identify strategies to modify risk for necrotizing enterocolitis

Although risk for necrotizing enterocolitis (NEC) is often presented from the perspective of a premature infant's vulnerability to nonmodifiable risk factors, in this paper we describe the evidence and present recommendations to manage modifiable risks that are amenable to clinical actions. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria, we present recommendations in the context of their supporting evidence in a way that balances risks (e.g. potential harm, cost) and benefits. Across the prenatal, intrapartum, early and late clinical course, strategies to limit NEC risk in premature infants are presented. Our goal is to summarize modifiable NEC risk factors, grade the evidence to offer quality improvement (QI) targets for healthcare teams and offer a patient-family advocate's perspective on how to engage parents to recognize and reduce NEC risk.

Umbilical Cord Milking in Infants Born at <37 Weeks of Gestation: A Systematic Review and Meta-Analysis

Umbilical cord milking (UCM) could be an alternative in cases where delayed umbilical cord clamping cannot be performed, therefore our objective was to evaluate the effects of UCM in newborns <37 weeks’ gestation. In this systematic review and meta-analysis, we searched MEDLINE, EMBASE, CINAHL, the Cochrane Database of Clinical Trials, the clinicaltrails.gov database for randomized UCM clinical trials with no language restrictions, which we then compared with other strategies. The sample included 2083 preterm infants. The results of our meta-analysis suggest that UCM in premature infants can reduce the risk of transfusion (relative risk (RR)= 0.78 [95% confidence interval (CI),0.67–0.90]) and increase hemoglobin(pooled weighted mean difference (PWMD)= 0.89 g/L[95%CI 0.55–1.22]) and mean blood pressure (PWMD=1.92 mmHg [95% CI 0.55–3.25]). Conversely, UCM seems to increase the risk of respiratory distress syndrome (RR = 1.54 [95% CI 1.03–2.29]), compared to the control groups. In infants born at <33 weeks, UCM was associated with a reduced risk of transfusion (RR= 0.81 [95%CI 0.66–0.99]), as well as higher quantities of hemoglobin (PWMD= 0.91 g/L[95%CI 0.50–1.32]). UCM reduces the risk of transfusion in preterm infants, and increases initial hemoglobin, hematocrit, and mean blood pressure levels with respect to controls.

Neuroprotection Strategies in Preterm Encephalopathy

Advances in neonatology have led to unprecedented improvements in neonatal survival such that those born as early as 22 weeks of gestation now have some chance of survival, and over 70% of those born at 24 weeks of gestation survive. Up to 50% of infants born extremely preterm develop poor outcomes involving long-term neurodevelopmental impairments affecting cognition and learning, or motor problems such as cerebral palsy. Poor outcomes arise because the preterm brain is vulnerable both to direct injury (by events such as intracerebral hemorrhage, infection, and/or hypoxia), or indirect injury due to disruption of normal development. This neonatal brain injury and/or dysmaturation is called "encephalopathy of prematurity". Current and future strategies to improve outcomes in this population include prevention of preterm birth, and pre-, peri-, and postnatal approaches to protect the developing brain. This review will describe mechanisms of preterm brain injury, and current and upcoming therapies in the antepartum and postnatal period to improve preterm encephalopathy.

Clamping the Umbilical Cord in Premature Deliveries (CUPiD): Neuromonitoring in the Immediate Newborn Period in a Randomized, Controlled Trial of Preterm Infants Born at <32 Weeks of Gestation

OBJECTIVE

To compare cerebral activity and oxygenation in preterm infants (<32 weeks of gestation) randomized to different cord clamping strategies.

STUDY DESIGN

Preterm infants born at <32 weeks of gestation were randomized to immediate cord clamping, umbilical cord milking (cord stripped 3 times), or delayed cord clamping for 60 seconds with bedside resuscitation. All infants underwent electroencephalogram (EEG) and cerebral near infrared spectroscopy for the first 72 hours after birth. Neonatal primary outcome measures were quantitative measures of the EEG (17 features) and near infrared spectroscopy over 1-hour time frames at 6 and 12 hours of life.

RESULTS

Forty-five infants were recruited during the study period. Twelve infants (27%) were randomized to immediate cord clamping, 19 (42%) to umbilical cord milking, and 14 (31%) to delayed cord clamping with bedside resuscitation. There were no significant differences between groups for measures of EEG activity or cerebral near infrared spectroscopy. Three of the 45 infants (6.7%) were diagnosed with severe IVH (2 in the immediate cord clamping group, 1 in the umbilical cord milking group; P = .35).

CONCLUSIONS

There were no differences in cerebral EEG activity and cerebral oxygenation values between cord management strategies at 6 and 12 hours.

TRIAL REGISTRATION

ISRCTN92719670.

Umbilical cord milking reduces the risk of intraventricular hemorrhage in preterm infants born before 32 weeks of gestation

OBJECTIVE

Intraventricular hemorrhage (IVH) is a common complication in extremely preterm infants. We aimed to demonstrate that umbilical cord milking (UCM) would reduce the incidence of IVH in this at risk population.

STUDY DESIGN

We compared the incidence of IVH in a prospective cohort of consecutively born preterm infants <32 weeks' gestation receiving UCM (n = 33) with a historical cohort that underwent immediate cord clamping (ICC) (n = 36).

RESULTS

No significant differences regarding perinatal characteristics were present between both groups except for chorioamnionitis and preterm rupture of membranes which were more frequent in the UCM group. There was a significant reduction in the incidence of IVH in the UCM group as compared to the ICC group (UCM vs. ICC = 12 vs. 33%, p = 0.037; OR = 0.276 (95% CI 0.079-0.967; p = 0.033; NNT = 4.7) and a reduction in the number of transfusions (UCM vs. ICC = 56 vs. 30%, p = 0.035; OR = 0.348 (0.129-0.938; p = 0.033; NNT = 3.8). UCM was safe for mothers (similar decrease in maternal hemoglobin) and offspring.

CONCLUSION

UCM significantly reduced the incidence of IVH in preterm infants < 32 weeks' gestation without associated complications for mother or offspring.

Haemodynamic effects of umbilical cord milking in premature sheep during the neonatal transition

OBJECTIVE

Umbilical cord milking (UCM) at birth may benefit preterm infants, but the physiological effects of UCM are unknown. We compared the physiological effects of two UCM strategies with immediate umbilical cord clamping (UCC) and physiological-based cord clamping (PBCC) in preterm lambs.

METHODS

At 126 days' gestational age, fetal lambs were exteriorised, intubated and instrumented to measure umbilical, pulmonary and cerebral blood flows and arterial pressures. Lambs received either (1) UCM without placental refill (UCMwoPR); (2) UCM with placental refill (UCMwPR); (3) PBCC, whereby ventilation commenced prior to UCC; or (4) immediate UCC. UCM involved eight milks along a 10 cm length of cord, followed by UCC.

RESULTS

A net volume of blood was transferred into the lamb during UCMwPR (8.8 mL/kg, IQR 8-10, P=0.01) but not during UCMwoPR (0 mL/kg, IQR -2.8 to 1.7) or PBCC (1.1 mL/kg, IQR -1.3 to 4.3). UCM had no effect on pulmonary blood flow, but caused large fluctuations in mean carotid artery pressures (MBP) and blood flows (CABF). In UCMwoPR and UCMwPR lambs, MBP increased by 12%±1% and 8%±1% and CABF increased by 32%±2% and 15%±2%, respectively, with each milk. Cerebral oxygenation decreased the least in PBCC lambs (17%, IQR 13-26) compared with UCMwoPR (26%, IQR 23-25, P=0.03), UCMwPR (35%, IQR 27-44, P=0.02) and immediate UCC (34%, IQR 28-41, P=0.02) lambs.

CONCLUSIONS

UCMwoPR failed to provide placental transfusion, and UCM strategies caused considerable haemodynamic disturbance. UCM does not provide the same physiological benefits of PBCC. Further review of UCM is warranted before adoption into routine clinical practice.

Benefits of umbilical cord milking versus delayed cord clamping on neonatal outcomes in preterm infants: A systematic review and meta-analysis

BACKGROUND

Optimum timing of umbilical cord clamping has not been established in preterm infants.

OBJECTIVES

We compared the short- and long-term effects of umbilical cord milking (UCM) versus delayed cord clamping (DCC) on infants born at less than 37 weeks of gestation.

SEARCH METHODS

A systematic review and meta-analysis was conducted according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" statement. We searched CINAHL, CENTRAL, EMBASE, MEDLINE, PubMed and ClinicalTrials.gov for relevant randomized controlled trials (RCTs).

SELECTION CRITERIA

We included individual and clustered RCTs comparing UCM to DCC for infants born before 37 weeks of gestation.

DATA COLLECTION AND ANALYSIS

Four reviewers independently assessed trial quality and eligibility for inclusion.

MAIN RESULTS

Two trials (255 preterm infants, 23 0/7 to 32 6/7 weeks of gestation) were included in the analysis. UCM was associated with fewer intraventricular hemorrhages (IVHs) (two trials, 255 infants; relative risk [RR] 0.45, 95% confidence interval [CI] 0.20 to 0.98, low quality of evidence) and UCM was an increased proportion of infants with a Bayley score at 2 years of age (two trials, 174 infants; Cognitive: RR 1.14, 95% CI 1.03 to 1.26, Language: RR 1.24, 95% CI 1.03 to 1.49, low quality of evidence) compared to DCC.

CONCLUSIONS

UCM wasn't reduced in-hospital mortality and need for transfusion compared to DCC. But our study suggests that UCM may lower the risk of IVH and improve certain neurodevelopmental outcomes compared to DCC in preterm infants.

Impact of umbilical cord milking and pasteurized donor human milk on necrotizing enterocolitis: a retrospective review

BACKGROUND

Necrotizing enterocolitis (NEC) is a serious complication of prematurity. Our objective was to evaluate the impact of an umbilical cord milking protocol (UCM) and pasteurized donor human milk (PDHM) on NEC rates in infants less than 30 weeks gestational age from January 1, 2010 to September 30, 2016. We hypothesized an incremental decrease in NEC after each intervention.

METHODS

We performed a retrospective review of 638 infants born less than 30 weeks gestational age. Infants were grouped into three epochs: pre-UCM/pre-PDHM (Epoch 1, n = 159), post-UCM/pre-PDHM (Epoch 2, n = 133), and post-UCM/post-PDHM (Epoch 3, n = 252). The incidence of NEC, surgical NEC, and NEC/death were compared. Logistic regression was used to determine independent significance of time epoch, gestational age, birth weight, and patent ductus arteriosus for NEC, surgical NEC, and death/NEC.

RESULTS

At birth, infants in Epoch 1 were younger than Epoch 2 and 3 (26.8 weeks versus 27.3 and 27.2, respectively, P = 0.036) and smaller (910 g versus 1012 and 983, respectively, P = 0.012). Across epochs, there was a significant correlation between patent ductus arteriosus treatment and NEC rate (P < 0.001, Cochran-Mantel-Haenszel). There was a significant decrease in rates of NEC, surgical NEC, and NEC/death between groups. Logistic regression showed this as significant for rates of NEC and surgical NEC between Epoch 1 and 3. Patent ductus arteriosus was a significant variable affecting the incidence of NEC, but not surgical NEC or death/NEC.

CONCLUSIONS

An umbilical cord milking protocol and pasteurized donor human milk availability was associated with decreased rates of NEC and surgical NEC. This suggests an additive effect of these interventions in preventing NEC.

Effect of Milking Maneuver in Preterm Infants: A Randomized Controlled Trial

OBJECTIVE

To assess the short and medium-term effects of milking maneuver (MM) compared with early cord clamping for infants born before 37 weeks of pregnancy.

MATERIAL AND METHODS

138 infants between 24+0 and 36+6 weeks of gestation were allocated to MM or early cord clamping. Primary outcomes were the requirement of red blood cell transfusions or phototherapy.

RESULTS

Initial hemoglobin was significantly higher in the MM group by 1.675 g/dL (p < 0.05) and initial hematocrit by 5.36% (p < 0.05), but no differences in the need of transfusion during the first 30 days after delivery were found (RR 0.8; 95% CI 0.22-2.85). Peak serum bilirubin was similar in both groups (11,097 ± 3.21 vs. 11,247 ± 3.56 mg/dL, p = 0.837). Phototherapy requirements were higher in the MM group (RR 1.62; 95% CI 1.1-2.38). No differences regarding the need of oral iron supplementation, platelet transfusion, respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, periventricular leukomalacia, meconium aspiration syndrome, use of surfactant, days of oxygen supplementation, need of vasopressors, length of stay in the neonatal intensive care unit, or postpartum hemorrhage were found.

CONCLUSION

MM does not reduce the need for red blood cell transfusions and increases phototherapy requirements in preterm infants.

Whole blood volumes associated with milking intact and cut umbilical cords in term newborns

OBJECTIVE

The objective of this study is to determine placental transfusion blood volumes with intact and cut umbilical cord milking in term newborns.

STUDY DESIGN

Sixty women at ≥37 weeks' gestation were enrolled. Following delivery, the umbilical cord was immediately clamped and cut to separate the newborn. Either intact umbilical cord milking (I-UCM) of the placental-umbilical cord unit or cut umbilical cord milking (C-UCM) of the cut umbilical cord segment was performed. For I-UCM, the cord underwent milking three or four times while being attached to placental circulation. For C-UCM, a 10, 20, or 30 cm cord segment was cut separately and milked four times. Blood volumes were compared between I-UCM and C-UCM methods.

RESULTS

Mean blood volume with I-UCM (×4) was increased compared to the 30 cm C-UCM technique (48.5 ± 19.0 vs. 24.8 ± 4.0 mL, P < 0.001). For C-UCM, blood volume increased proportionally to cord length and, by the second milking, 98.1 ± 4.5% of blood volume was delivered.

CONCLUSION

I-UCM provides a greater blood volume than C-UCM. With C-UCM, milking the cord more than twice offers no additional advantage.

Safety of umbilical cord milking in very preterm neonates: a randomized controlled study

Objective

To investigate the safety of umbilical cord milking on both the mother and neonate among very preterm deliveries of less than 33 weeks of gestation.

Methods

Pregnant women who were expected to deliver at between 24 0/7 and 32 6/7 weeks of gestation were randomized to either the umbilical cord milking or immediate cord clamping group. Maternal and neonatal data associated with delivery, in addition to neonatal morbidity and mortality data, were collected and analyzed.

Results

Of the 66 preterm deliveries included in the study, 34 were randomized into the milking and 32 into the clamping group. Differences between maternal pre- and post-partum hemoglobin levels were 1.35 g/dL in the milking and 1.58 g/dL in the clamping group (P=0.451). Neonatal Apgar scores at both 1 and 5 minutes, initial blood gas analysis results, body temperature at admission, need for early intubation, and maximum bilirubin levels were all similar between the 2 groups. However, neonatal hemoglobin levels at birth (15.79 vs. 14.69 g/dL; P<0.05) and at 24 hours of age (14.83 vs. 13.29 g/dL; P<0.05) were significantly higher in the milking group. Neonates in the clamping group required more blood transfusion (1.78 vs. 0.93; P=0.049), and a higher percentage of neonates in the clamping group required inotropic drugs (63% vs. 29%; P=0.007). The mortality rate was significantly lower in the milking group (6% vs. 28%; P=0.015).

Conclusion

Umbilical cord milking can be a safe and beneficial procedure for both the mother and the neonate in deliveries of less than 33 weeks of gestation.

Towards evidence-based resuscitation of the newborn infant

Effective resuscitation of the newborn infant has the potential to save many lives around the world and reduce disabilities in children who survive peripartum asphyxia. In this Series paper, we highlight some of the important advances in the understanding of how best to resuscitate newborn infants, which includes monitoring techniques to guide resuscitative efforts, increasing awareness of the adverse effects of hyperoxia, delayed umbilical cord clamping, the avoidance of routine endotracheal intubation for extremely preterm infants, and therapeutic hypothermia for hypoxic-ischaemic encephalopathy. Despite the challenges of performing high-quality clinical research in the delivery room, researchers continue to refine and advance our knowledge of effective resuscitation of newborn infants through scientific experiments and clinical trials.

Providing a Placental Transfusion in Newborns Who Need Resuscitation

Over the past decade, there have been several studies and reviews on the importance of providing a placental transfusion to the newborn. Allowing a placental transfusion to occur by delaying the clamping of the umbilical cord is an extremely effective method of enhancing arterial oxygen content, increasing cardiac output, and improving oxygen delivery. However, premature and term newborns who require resuscitation have impaired transitional hemodynamics and may warrant different methods to actively provide a placental transfusion while still allowing for resuscitation. In this review, we will provide evidence for providing a placental transfusion in these circumstances and methods for implementation. Several factors including cord clamping time, uterine contractions, umbilical blood flow, respirations, and gravity play an important role in determining placental transfusion volumes. Finally, while many practitioners agree that a placental transfusion is beneficial, it is not always straightforward to implement and can be performed using different methods, making this basic procedure important to discuss. We will review three placental transfusion techniques: delayed cord clamping, intact umbilical cord milking, and cut-umbilical cord milking. We will also review resuscitation with an intact cord and the evidence in term and preterm newborns supporting this practice. We will discuss perceived risks versus benefits of these procedures. Finally, we will provide key straightforward concepts and implementation strategies to ensure that placental-to-newborn transfusion can become routine practice at any institution.

The Role of Mucosal Immunity in the Pathogenesis of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is the most devastating gastrointestinal disease of prematurity. Although the precise cause is not well understood, the main risk factors thought to contribute to NEC include prematurity, formula feeding, and bacterial colonization. Recent evidence suggests that NEC develops as a consequence of intestinal hyper-responsiveness to microbial ligands upon bacterial colonization in the preterm infant, initiating a cascade of aberrant signaling events, and a robust pro-inflammatory mucosal immune response. We now have a greater understanding of important mechanisms of disease pathogenesis, such as the role of cytokines, immunoglobulins, and immune cells in NEC. In this review, we will provide an overview of the mucosal immunity of the intestine and the relationship between components of the mucosal immune system involved in the pathogenesis of NEC, while highlighting recent advances in the field that have promise as potential therapeutic targets. First, we will describe the cellular components of the intestinal epithelium and mucosal immune system and their relationship to NEC. We will then discuss the relationship between the gut microbiota and cell signaling that underpins disease pathogenesis. We will conclude our discussion by highlighting notable therapeutic advancements in NEC that target the intestinal mucosal immunity.

[Focus on placental transfusion for preterm neonates: Delayed cord clamping and/or milking?]

Anemia of prematurity remains a common complication despite recent advances in perinatal and neonatal medicine. The delayed cord clamping (at least 30seconds as recommended) has several benefits: increased hemoglobin and hematocrit levels at birth, improved initial hemodynamic, decreased incidence of transfusions and intraventricular hemorrhages. When the birth transition is difficult, wait 30seconds before clamping can be impossible. So as not to interfere with the neonatal resuscitation, the "milking" has been proposed as an alternative method to the delayed cord clamping. This is a safe and easy method, which can be done either by an obstetrician or pediatrician with comparable results for the child on his hemodynamic, hematological and neurological status. It still lacks technical information on this method and neurodevelopmental outcomes of these preterm infants.

Preterm Cord Blood Contains a Higher Proportion of Immature Hematopoietic Progenitors Compared to Term Samples

BACKGROUND

Cord blood contains high number of hematopoietic cells that after birth disappear. In this paper we have studied the functional properties of the umbilical cord blood progenitor cells collected from term and preterm neonates to establish whether quantitative and/or qualitative differences exist between the two groups.

METHODS AND RESULTS

Our results indicate that the percentage of total CD34+ cells was significantly higher in preterm infants compared to full term: 0.61% (range 0.15-4.8) vs 0.3% (0.032-2.23) p = 0.0001 and in neonates <32 weeks of gestational age (GA) compared to those ≥32 wks GA: 0.95% (range 0.18-4.8) and 0.36% (0.15-3.2) respectively p = 0.0025. The majority of CD34+ cells co-expressed CD71 antigen (p<0.05 preterm vs term) and grew in vitro large BFU-E, mostly in the second generation. The subpopulations CD34+CD38- and CD34+CD45- resulted more represented in preterm samples compared to term, conversely, Side Population (SP) did not show any difference between the two group. The absolute number of preterm colonies (CFCs/10microL) resulted higher compared to term (p = 0.004) and these progenitors were able to grow until the third generation maintaining an higher proportion of CD34+ cells (p = 0.0017). The number of colony also inversely correlated with the gestational age (Pearson r = -0.3001 p<0.0168).

CONCLUSIONS

We found no differences in the isolation and expansion capacity of Endothelial Colony Forming Cells (ECFCs) from cord blood of term and preterm neonates: both groups grew in vitro large number of endothelial cells until the third generation and showed a transitional phenotype between mesenchymal stem cells and endothelial progenitors (CD73, CD31, CD34 and CD144)The presence, in the cord blood of preterm babies, of high number of immature hematopoietic progenitors and endothelial/mesenchymal stem cells with high proliferative potential makes this tissue an important source of cells for developing new cells therapies.

Prevention of the anaemia of prematurity

Despite recent advances in neonatal and perinatal medicine, extremely low birth weight infants (ELBW) are at high risk of developing anaemia of prematurity (AOP) requiring packed red blood cell (RBC) transfusions. The benefit of transfusing allogenic RBCs for AOP is a controversial issue, except for disturbances in tissue oxygenation. Although the role of erythropoietin (EPO) in the pathophysiology of AOP is well known, neither early nor late recombinant human EPO therapy alters the number or volume of RBC transfusions. It is also known that one-half of the feto-placental blood volume remains outside the newborn infant's circulation at 30 weeks of gestation if the umbilical cord is clamped immediately. Delayed cord clamping (DCC) and umbilical cord milking (UCM) are the main methods for enhancing placental transfusion. The basic principle of these approaches depends on providing high haemoglobin (Hb) levels to premature infants in the delivery room. The enhancement of placental transfusion clearly results in higher Hb levels at birth, reducing the need for RBC transfusions as well as creating a better haemodynamic status during the initial hours of life. To date, enhancement of placental transfusion in the delivery room by either DCC or UCM seems to be the best preventive measure for AOP. Yet, studies on the associated neurodevelopmental outcomes are insufficient to reach a conclusion. This review summarizes the pathophysiology, treatment and preventative strategies of anaemia of prematurity in light of the current literature.