Delayed cord clamping is associated with improved dynamic cerebral autoregulation and decreased incidence of intraventricular hemorrhage in preterm infants

Deferred Cord Clamping in Twin Pregnancies Across Canada: A National Survey of Practices

OBJECTIVE

Guidelines recommending deferred cord clamping (DCC), delaying cord clamping for at least 30 seconds post-birth, have shown significant benefits in preterm singleton births. However, evidence supporting DCC in twins is scarce due to limited trial data, leading to practice variations. This study aims to assess current reported DCC practices for twin pregnancies in tertiary hospitals across Canada.

METHODS

A web-based survey was distributed to neonatologists and obstetrician investigators associated with the Canadian Neonatal and Preterm Birth Networks operating maternity and neonatal units.

RESULTS

The site response rate was 93% (28/30 sites), with 83% (25/30) for neonatologists and 56% (17/30) for obstetricians. The majority had a local protocol for twin pregnancies (obstetricians 13/17, neonatologists 21/25). While all centres practised DCC in dichorionic-diamniotic twins, a difference was noted for monochorionic-diamniotic twins, with 56% of neonatologists and 65% of obstetricians performing DCC. During cesarean delivery, most obstetricians (76.5%) placed the firstborn on the mother's thighs. Neonatologists varied in their practices, with 32% placing the baby on the mother's abdomen, 32% on the mother's thighs, and 28% holding the baby at the height of the perineum. Divergent opinions were observed regarding contraindications, including risks of postpartum hemorrhage and velamentous cord insertion.

CONCLUSIONS

DCC is reported to be practised in most twin deliveries among Canadian Neonatal and Preterm Birth Network centres. However, there are wide variations in practice, especially concerning the characteristics of the twins in which DCC is performed. Future research should investigate optimal cord clamping management in twins to standardize practices and maximize benefits.

Cerebral autoregulation in pediatric and neonatal intensive care: A scoping review

Deranged cerebral autoregulation (CA) is associated with worse outcome in adult brain injury. Strategies for monitoring CA and maintaining the brain at its 'best CA status' have been implemented, however, this approach has not yet developed for the paediatric population. This scoping review aims to find up-to-date evidence on CA assessment in children and neonates with a view to identify patient categories in which CA has been measured so far, CA monitoring methods and its relationship with clinical outcome if any. A literature search was conducted for studies published within 31st December 2022 in 3 bibliographic databases. Out of 494 papers screened, this review includes 135 studies. Our literature search reveals evidence for CA measurement in the paediatric population across different diagnostic categories and age groups. The techniques adopted, indices and thresholds used to assess and define CA are heterogeneous. We discuss the relevance of available evidence for CA assessment in the paediatric population. However, due to small number of studies and heterogeneity of methods used, there is no conclusive evidence to support universal adoption of CA monitoring, technique, and methodology. This calls for further work to understand the clinical impact of CA monitoring in paediatric and neonatal intensive care.

A randomised controlled trial comparing umbilical cord milking to delayed cord clamping at birth in preterm infants 28-36 weeks gestational age

Delayed cord clamping (DCC) is an established practice in perinatology with multiple benefits. However, in instances where the implementation of DCC is not viable, it needs alternatives, especially during caesarean deliveries. A non-inferiority randomized, non-blinded, trial was conducted at a tertiary care referral unit in South India among the preterm newborns (28-36 weeks) randomized to DCC as opposed to intact-umbilical cord milking (UCM). The primary objective was to compare the mean haemoglobin values between the two groups, and the secondary outcome was to compare death and/or major IVH (> Grade II). Of the 132 eligible newborn infants, 99 were randomized to two study groups. Of the 59 and 40 randomised to UCM and DCC, 54 and 36 received the allocated intervention respectively. Preterm infants who underwent UCM had significantly higher haemoglobin (19.97 ± 1.44) as compared to DCC group (18.62 ± 0.98) p-0.0001. The rates of mortality and/or major IVH were comparable between the two groups.

CONCLUSION

UCM may be a feasible alternative to DCC especially in settings where the latter is not achievable, without increasing the risk of adverse effects to the preterm infants, this finding needing further confirmation with larger sample.

TRIAL REGISTRATION

CTRI (Clinical Trial Registry-India) registration number: CTRI/2020/04/024566 (registered prospectively on 13/04/2020).

WHAT IS KNOWN

• Delayed cord clamping (DCC) is recommended as a standard of care for all the stable term and preterm newborn babies at birth.

WHAT IS NEW

• Intact umbilical cord milking may be a reasonable choice of cord management when DCC is unsuccessful, without increasing adverse effects for the new born.

Comparing two different placental transfusion strategies for very preterm infants at birth: a matched-pairs study

OBJECTIVE

To evaluate the clinical outcomes of using the extra-uterine placental transfusion (EPT) approach in very preterm infants (VPIs, gestational age <32 weeks) and compare this to delayed cord clamping (DCC) after birth.

METHODS

In this matched pairs study, we compared the clinical outcomes of the EPT group to those of the DCC group. EPT were performed in fifty-three VPIs, of whom 27 were singletons and 25 were twins. The singleton VPIs were matched for gestational age (±5 days) and delivery mode, and the twin VPIs were matched between each other with the first twin subjected to DCC and the second twin to EPT. Data on the infants were collected and analysed as an overall group. A twin subgroup consisting of DCC and EPT groups was also analysed separately. The primary study outcome was either death or major morbidities.

RESULTS

In total, 100 infants were included (n = 50 EPT group, n = 50 DCC group). The gestational ages of the DCC and EPT groups were (29.16 ± 1.76) and (29.12 ± 1.84) weeks, respectively. There were no differences in either deaths or major morbidities and other clinical outcomes, including the resuscitation variables, haemoglobin levels and red blood cell transfusion, between the two groups. In twin subgroups (gestational age 29.05 ± 1.89 weeks), EPT was associated with a higher rate of necrotizing enterocolitis (NEC) when compared with DCC (odds ratio = 7 (95% CI, 1.06 to 56.89), p = 0.031).

CONCLUSIONS

In twin subgroups, the incidence of NEC was higher in the EPT group when compared to the DCC group and therefore based on an abundance of caution the use of EPT in very preterm twins is not recommended.

Effect of delayed cord clamping on cerebral hemodynamics in preterm infants

Background

Unstable cerebral hemodynamics is an important cause of intracranial hemorrhage in premature infants. The increased blood flow of delayed cord clamping (DCC) compared to immediate cord clamping (ICC) is equivalent to 1/3-1/4 of newborn blood volume. Our objective was to assess whether the increased blood flow causes fluctuations in cerebral blood flow and how.

Methods

This experiment was a prospective, observational study. Neonatologists selected preterm infants eligible for inclusion and exclusion, and divided them into DCC group and ICC group according to the way of umbilical cord ligation performed by obstetrics department, and matched them 1:1 according to gestational age. The peak systolic velocity （PSV) ，end diastolic velocity (EDV)，and resistance index (RI) of middle cerebral artery was measured by Mindray M9 color ultrasonic diagnostic instrument within 1 h, 24±1 h, 48±1 h, 72±1 h, respectively.

Results

There was no significant difference in PSV, EDV and RI in middle cerebral artery between DCC group and ICC group (P > 0.05). There were no significant differences between groups and time (P > 0.05). The hemoglobin and hematocrit in DCC group were higher than those in ICC group within 2 h after birth (P < 0.05). (P > 0.05).

Conclusion

DCC can increase hemoglobin and hematocrit in preterm infants, but does not cause cerebral blood flow fluctuation within a certain range. DCC is a safe method of placental transfusion.

With or Without Nasal Continuous Positive Airway Pressure During Delayed Cord Clamping in Premature Infants <32 Weeks: A Randomized Controlled Trial Using an Intention-To-Treat Analysis

OBJECTIVE

To assess whether providing nasal continuous positive airway pressure (nCPAP) during delayed cord clamping is beneficial for preterm infants <32 weeks.

STUDY DESIGN

A randomized controlled trial was performed from March 2020 to May 2021. Premature infants (<32 weeks of gestational age; n = 160) were allocated to receive at least 60 s of delayed cord clamping with nCPAP (DCC+nCPAP; n = 80) or without nCPAP (DCC only; n = 80). For both groups, after the umbilical cord was clamped, the infants were carried immediately to the resuscitation room to continue receiving standard transition. The primary outcome was the mechanical ventilation (MV) rate within 24 h of life. The measurements related to early respiratory support effect before cord clamping including positive end-expiratory pressure (PEEP) and FiO₂ during transition/leaving the delivery room, intubation rate during transition, pulmonary surfactant (PS) administration ≥2 times after birth, extubation failure, and incidence of bronchopulmonary dysplasia (BPD) were collected as the secondary outcomes. Furthermore, other neonatal short-term outcomes and safety assessment were also included.

RESULTS

The measurements were calculated using intention-to-treat analysis. The median time for cord clamping were 60 s with interquartile range (IQR) (60.00-60.00 vs. 60.00-70.00) in both groups. There were no difference in the primary outcome of MV rate within 24 h of life (p = 0.184). The arterial blood gas pH at 1 h after birth in the DCC+nCPAP group was 7.28 ± 0.08 vs. 7.25 ± 0.07 in the control group (mean difference = 0.01, 95% CI: -0.01-0.05, p = 0.052), which approached statistical significance. There was no significant statistical difference in the other short-term neonatal outcomes and the safety indicators between the two groups.

CONCLUSIONS

Our study showed that delayed cord clamping with nCPAP was feasible and safe in preterm infants with gestational age <32 weeks. Although there was a trend toward a higher arterial blood gas pH at 1 h after birth in the DCC+nCPAP group, DCC+nCPAP neither resulted in a corresponding measurable clinical improvement nor did it reduce subsequent neonatal morbidity. A larger multi-center study including more infants with gestational age <28 weeks is needed to evaluate the full effects of DCC in combination with nCPAP in preterm infants.

A neonatal neuroNICU collaborative approach to neuromonitoring of posthemorrhagic ventricular dilation in preterm infants

Morbidity and mortality in prematurely born infants have significantly improved due to advancement in perinatal care, development of NeuroNICU collaborative multidisciplinary approaches, and evidence-based management protocols that have resulted from a better understanding of perinatal risk factors and neuroprotective treatments. In premature infants with intraventricular hemorrhage (IVH), the detrimental secondary effect of posthemorrhagic ventricular dilation (PHVD) on the neurodevelopmental outcome can be mitigated by surgical intervention, though management varies considerably across institutions. Any benefit derived from the use of neuromonitoring to optimize surgical timing and technique stands to improve neurodevelopmental outcome. In this review, we summarize (1) the approaches to surgical management of PHVD in preterm infants and outcome data; (2) neuromonitoring modalities and the effect of neurosurgical intervention on this data; (3) our resultant protocol for the monitoring and management of PHVD. In particular, our protocol incorporates cerebral near-infrared spectroscopy (NIRS) and transcranial doppler ultrasound (TCD) to better understand cerebral physiology and to enable the hypothesis-driven study of the management of PHVD. IMPACT: Review of the published literature concerning the use of near-infrared spectroscopy (NIRS) and a cerebral Doppler ultrasound to study the effect of cerebrospinal fluid drainage on infants with posthemorrhagic ventricular dilation. Presentation of our institution's evidence-based protocol for the use of NIRS and cerebral Doppler ultrasound to study the optimal neurosurgical treatment of posthemorrhagic ventricular dilation, an as yet inadequately studied area.

Delayed cord clamping: Time for physiologic implementation

Delayed cord clamping has been shown to be beneficial in both preterm and term babies. Practice guidelines have not been consistent between centers and the practice of delayed cord clamping has not been standardized. The concept of physiologic-based cord clamping emerged into practice as well. Cord milking has different physiological effect and might be harmful in preterm babies.

[Effect of delayed cord clamping and umbilical cord milking on cerebral hemodynamics in preterm infants: a randomized double-blind controlled trial]

OBJECTIVE

To compare the effect of delayed cord clamping (DCC) versus umbilical cord milking (UCM) on cerebral blood flow in preterm infants.

METHODS

This was a single-center, prospective, double-blind, randomized controlled trial. A total of 46 preterm infants, with a gestational age of 30-33⁺⁶ weeks, who were born in Suining Central Hospital from November 2, 2018 to November 15, 2019 were enrolled and randomly divided into DCC group and UCM group, with 23 infants in each group. The primary outcome indexes included cerebral hemodynamic parameters[peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI)] measured by ultrasound within 0.5-1 hour, (24±1) hours, (48±1) hours, and (72±1) hours after birth. Secondary outcome indexes included hematocrit, hemoglobin, red blood cell count, and serum total bilirubin levels on the first day after birth and the incidence rate of intraventricular hemorrhage during hospitalization.

RESULTS

A total of 21 preterm infants in the DCC group and 23 in the UCM group were included in the statistical analysis. There was no significant difference in PSV, EDV, and RI between the two groups at all time points after birth (P > 0.05). There was also no significant difference between the two groups in the hematocrit, hemoglobin, red blood cell count and total bilirubin levels on the first day after birth, and the incidence rate of intraventricular hemorrhage during hospitalization (P > 0.05).

CONCLUSIONS

DCC and UCM have a similar effect on cerebral hemodynamics in preterm infants with a gestational age of 30-33⁺⁶ weeks.

[Risk factors for endotracheal intubation during resuscitation in the delivery room among very preterm infants]

OBJECTIVE

To explore the risk factors for endotracheal intubation during resuscitation in the delivery room among very preterm infants.

METHODS

A retrospective analysis was performed for 455 very preterm infants who were admitted to the neonatal intensive care unit from January 2017 to December 2019. They were divided into an intubation group (n=79) and a non-intubation group (n=376) according to whether endotracheal intubation was performed during resuscitation. The risk factors for endotracheal intubation during resuscitation were evaluated by multivariate logistic regression analysis.

RESULTS

The intubation rate was 17.4% (79/455). Compared with the intubation group, the non-intubation group had significantly higher gestational age, birth weight, and rates of caesarean birth, delayed cord clamping (DCC), resuscitation quality improvement, regular use of antenatal glucocorticoids in mothers and premature rupture of membranes > 18 hours (P < 0.05), but significantly lower rates of maternal gestational diabetes mellitus, placental abruption, placenta previa or placenta previa status, and maternal thyroid dysfunction (P < 0.05). Regular use of antenatal glucocorticoids in mothers (OR=0.368, P < 0.05) and DCC (OR=0.222, P < 0.05) were protective factors against intubation during resuscitation, while younger gestational age, birth weight < 750 g, maternal gestational diabetes mellitus, and placenta previa or placenta previa status were risk factors for intubation during resuscitation (P < 0.05).

CONCLUSIONS

Very preterm infants with younger gestational age, birth weight < 750 g, maternal diabetes mellitus, placenta previa or placenta previa status may have a higher risk for endotracheal intubation after birth. The regular use of antenatal glucocorticoids and DCC can reduce the risk of intubation during resuscitation in very preterm infants.

[Effect of delayed cord clamping and umbilical cord milking on cerebral hemodynamics in preterm infants: a randomized double-blind controlled trial]

OBJECTIVE

To compare the effect of delayed cord clamping (DCC) versus umbilical cord milking (UCM) on cerebral blood flow in preterm infants.

METHODS

This was a single-center, prospective, double-blind, randomized controlled trial. A total of 46 preterm infants, with a gestational age of 30-33+6 weeks, who were born in Suining Central Hospital from November 2, 2018 to November 15, 2019 were enrolled and randomly divided into DCC group and UCM group, with 23 infants in each group. The primary outcome indexes included cerebral hemodynamic parameters[peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI)] measured by ultrasound within 0.5-1 hour, (24±1) hours, (48±1) hours, and (72±1) hours after birth. Secondary outcome indexes included hematocrit, hemoglobin, red blood cell count, and serum total bilirubin levels on the first day after birth and the incidence rate of intraventricular hemorrhage during hospitalization.

RESULTS

A total of 21 preterm infants in the DCC group and 23 in the UCM group were included in the statistical analysis. There was no significant difference in PSV, EDV, and RI between the two groups at all time points after birth (P > 0.05). There was also no significant difference between the two groups in the hematocrit, hemoglobin, red blood cell count and total bilirubin levels on the first day after birth, and the incidence rate of intraventricular hemorrhage during hospitalization (P > 0.05).

CONCLUSIONS

DCC and UCM have a similar effect on cerebral hemodynamics in preterm infants with a gestational age of 30-33+6 weeks.

Neonatal NIRS monitoring: recommendations for data capture and review of analytics

Brain injury is one of the most consequential problems facing neonates, with many preterm and term infants at risk for cerebral hypoxia and ischemia. To develop effective neuroprotective strategies, the mechanistic basis for brain injury must be understood. The fragile state of neonates presents unique research challenges; invasive measures of cerebral blood flow and oxygenation assessment exceed tolerable risk profiles. Near-infrared spectroscopy (NIRS) can safely and non-invasively estimate cerebral oxygenation, a correlate of cerebral perfusion, offering insight into brain injury-related mechanisms. Unfortunately, lack of standardization in device application, recording methods, and error/artifact correction have left the field fractured. In this article, we provide a framework for neonatal NIRS research. Our goal is to provide a rational basis for NIRS data capture and processing that may result in better comparability between studies. It is also intended to serve as a primer for new NIRS researchers and assist with investigation initiation.

Umbilical cord blood cells for the treatment of preterm white matter injury: Potential effects and treatment options

Preterm birth is a global public health problem. A large number of preterm infants survive with preterm white matter injury (PWMI), which leads to neurological deficits, and has multifaceted etiology, clinical course, monitoring, and outcomes. The principal upstream insults leading to PWMI initiation are hypoxia-ischemia and infection and/or inflammation and the key target cells are late oligodendrocyte precursor cells. Current PWMI treatments are mainly supportive, and thus have little effect in terms of protecting the immature brain or repairing injury to improve long-term outcomes. Umbilical cord blood (UCB) cells comprise abundant immunomodulatory and stem cells, which have the potential to reduce brain injury, mainly due to anti-inflammatory and immunomodulatory mechanisms, and also through their release of neurotrophic or growth factors to promote endogenous neurogenesis. In this review, we briefly summarize PWMI pathogenesis and pathophysiology, and the specific properties of different cell types in UCB. We further explore the potential mechanism by which UCB can be used to treat PWMI, and discuss the advantages of and potential issues related to UCB cell therapy. Finally, we suggest potential future studies of UCB cell therapy in preterm infants.

Cerebral Autoregulation in Sick Infants: Current Insights

Cerebrovascular autoregulation is the ability to maintain stable cerebral blood flow within a range of cerebral perfusion pressures. When cerebral perfusion pressure is outside the limits of effective autoregulation, the brain is subjected to hypoperfusion or hyperperfusion, which may cause vascular injury, hemorrhage, and/or hypoxic white matter injury. Infants born preterm, after fetal growth restriction, with congenital heart disease, or with hypoxic-ischemic encephalopathy are susceptible to a failure of cerebral autoregulation. Bedside assessment of cerebrovascular autoregulation would offer the opportunity to prevent brain injury. Clinicians need to know which patient populations and circumstances are associated with impaired/absent cerebral autoregulation.

Recent advances in perinatal neuroprotection

Perinatal brain injury is a major cause of neurological disability in both premature and term infants. In this review, we summarize the evidence behind some established neuroprotective practices such as administration of antenatal steroids, intrapartum magnesium for preterm delivery, and therapeutic hypothermia. In addition, we examine emerging practices such as delayed cord clamping, postnatal magnesium administration, recombinant erythropoietin, and non-steroidal anti-inflammatory agents and finally inform the reader about novel interventions, some of which are currently in trials, such as xenon, melatonin, topiramate, allopurinol, creatine, and autologous cord cell therapy.