EARLY VERSUS DELAYED CORD CLAMPING AT BIRTH; IN SICKNESS AND IN HEALTH

The BabySaver: Design of a New Device for Neonatal Resuscitation at Birth with Intact Placental Circulation

The initial bedside care of premature babies with an intact cord has been shown to reduce mortality; there is evidence that resuscitation of term babies with an intact cord may also improve outcomes. This process has been facilitated by the development of bedside resuscitation surfaces. These new devices are unaffordable, however, in most of sub-Saharan Africa, where 42% of the world’s 2.4 million annual newborn deaths occur. This paper describes the rationale and design of BabySaver, an innovative low-cost mobile resuscitation unit, which was developed iteratively over five years in a collaboration between the Sanyu Africa Research Institute (SAfRI) in Uganda and the University of Liverpool in the UK. The final BabySaver design comprises two compartments; a tray to provide a firm resuscitation surface, and a base to store resuscitation equipment. The design was formed while considering contextual factors, using the views of individual women from the community served by the local hospitals, medical staff, and skilled birth attendants in both Uganda and the UK.

Maternity health professionals' perspectives of cord clamp timing, cord blood banking and cord blood donation: a qualitative study

Background

Parents today have several options for the management of their infant’s cord blood during the third stage of labour. Parents can choose to have their infant’s cord clamped early or to have deferred cord clamping. If the cord is clamped early, cord blood can be collected for private cord blood banking or public cord blood donation for use later if needed. If cord clamping is deferred, the placental blood physiologically transfuses to the neonate and there are physiological advantages to this. These benefits include a smoother cardiovascular transition and increased haemoglobin levels while not interfering with the practice of collecting cord blood for gases if needed. The aim of this study is to explore Australian maternity health professionals’ perspectives towards cord clamp timing, cord blood banking and cord blood donation.

Methods

Fourteen maternity health professionals (midwives and obstetricians) from both private and public practice settings in Australia participated in semi-structured interviews either in person or by telephone. Interviews were transcribed and data analysed using thematic analysis.

Results

Overall there was strong support for deferred cord clamping, and this was seen as important and routinely discussed with parents as part of antenatal care. However, support did not extend to the options of cord blood banking and donation and to routinely informing parents of these options even when these were available at their birthing location.

Conclusion

Formalised education for maternity health professionals is needed about the benefits and implications of cord blood banking and cord blood donation so that they have the confidence to openly discuss all options of cord clamp timing, cord blood banking and cord blood donation to facilitate informed decision-making by parents.

Transition from fetal to neonatal circulation: Modeling the effect of umbilical cord clamping

Hemodynamics of the fetal to neonatal transition are orchestrated through complex physiological changes and results in cardiovascular adaptation to the adult biventricular circulation. Clinical practice during this critical period can influence vital organ physiology for normal newborns, premature babies and congenital heart defect patients. Particularly, the timing of the cord clamping procedure, immediate (ICC) vs. delayed cord clamping (DCC), is hypothesized to be an important factor for the transitory fetal hemodynamics. The clinical need for a quantitative understanding of this physiology motivated the development of a lumped parameter model (LPM) of the fetal cardio-respiratory system covering the late-gestation to neonatal period. The LPM was validated with in vivo clinical data and then used to predict the effects of cord clamping procedures on hemodynamics and vital gases. Clinical time-dependent resistance functions to simulate the vascular changes were introduced. For DCC, placental transfusion (31.3 ml) increased neonatal blood volume by 11.7%. This increased blood volume is reflected in an increase in preload pressures by ~20% compared to ICC, which in turn increased the cardiac output (CO) by 20% (COICC=993 ml/min; CODCC=1197 ml/min). Our model accurately predicted dynamic flow patterns in vivo. DCC was shown to maintain oxygenation if the onset of pulmonary respiration was delayed or impaired. On the other hand, a significant 25% decrease in oxygen saturations was observed when applying ICC under the same physiological conditions. We conclude that DCC has a significant impact on newborn hemodynamics, mainly because of the improved blood volume and the sustained placental respiration.

Investigating developmental cardiovascular biomechanics and the origins of congenital heart defects

Innovative research on the interactions between biomechanical load and cardiovascular (CV) morphogenesis by multiple investigators over the past 3 decades, including the application of bioengineering approaches, has shown that the embryonic heart adapts both structure and function in order to maintain cardiac output to the rapidly growing embryo. Acute adaptive hemodynamic mechanisms in the embryo include the redistribution of blood flow within the heart, dynamic adjustments in heart rate and developed pressure, and beat to beat variations in blood flow and vascular resistance. These biomechanically relevant events occur coincident with adaptive changes in gene expression and trigger adaptive mechanisms that include alterations in myocardial cell growth and death, regional and global changes in myocardial architecture, and alterations in central vascular morphogenesis and remodeling. These adaptive mechanisms allow the embryo to survive these biomechanical stresses (environmental, maternal) and to compensate for developmental errors (genetic). Recent work from numerous laboratories shows that a subset of these adaptive mechanisms is present in every developing multicellular organism with a “heart” equivalent structure. This chapter will provide the reader with an overview of some of the approaches used to quantify embryonic CV functional maturation and performance, provide several illustrations of experimental interventions that explore the role of biomechanics in the regulation of CV morphogenesis including the role of computational modeling, and identify several critical areas for future investigation as available experimental models and methods expand.