A physiologic approach to cord clamping: Clinical issues

Niermeyer Maternal Health, Neonatology, and Perinatology (2015) 1:21 DOI 10.1186/s40748-015-0022-5 REVIEW Open Access A physiologic approach to cord clamping: Clinical issues Susan Niermeyer Abstract Background: Recent experimental physiology data and a large, population-based observational study have changed umbilical cord clamping from a strictly time-based construct to a more complex equilibrium involving circulatory changes and the onset of respirations in the newly born infant. However, available evidence is not yet sufficient to optimize the management of umbilical cord clamping. Findings: Current guidelines vary in their recommendations and lack advice for clinicians who face practical dilemmas in the delivery room. This review examines the evidence around physiological outcomes of delayed cord clamping and cord milking vs. immediate cord clamping. Gaps in the existing evidence are highlighted, including the optimal time to clamp the cord and the interventions that should be performed before clamping in infants who fail to establish spontaneous respirations or are severely asphyxiated, as well as those who breathe spontaneously. Conclusion: Behavioral and technological changes informed by further research are needed to promote adoption and safe practice of physiologic cord clamping. Keywords: Umbilical cord, Placental transfusion, Resuscitation, Respiration, Infant, Newborn, Infant, Premature Background “In the time of Hippocrates the cord was not cut until the placenta was delivered….Since the time of Levret it has been established as a general rule, among accoucheurs, to separate the child from the mother as soon as it has passed through the vulva, and that it is never necessary to wait for the expulsion of the foetal appendages. At first view the conduct of the ancients appears to be more rational and more physiological than that of the moderns; it seems that the placenta ought immediately to follow the foetus, or at least be separated from the uterus before the cord can be prudently cut; that before it is divided, the circulation ought to be permitted gradually to take on its new type, which soon becomes similar to that of the adult; but in reality it is not perceived that the present mode of practice produces the least inconvenience to the foetus, and is certainly better for the mother.” 1 – Prof. A.A. Velpeau, 1829 [1] Correspondence: Section of Neonatology, University of Colorado School of Medicine, 13121 E. 17th Avenue, Mail Stop 8402, Aurora, CO 80045, USA For centuries, lively debate has surrounded the question of when to clamp and cut the umbilical cord of the newly born infant, and practices have ranged from one extreme to the other. From the time of the Ancient Greeks, midwives have described the value of waiting to clamp the cord until pulsations stop or until the placenta is delivered [1]. This approach is taken to its furthest modern extent in Lotus birth, when the umbilical cord and placenta remain attached to the infant until natural separation at the umbilicus occurs after several days. As Prof. Velpeau pointed out in his Treatise on Midwifery in 1829, a different practice arose among accoucheurs, male midwives or obstetricians, who perceived that immediate cord clamping and cutting offered benefit to the mother and posed no “inconvenience” to the newborn [1]. Recently, the obstetrical practice of immediate cord clamping has been modified by policy statements from the American College of Obstetricians and Gynecologists (ACOG), the Royal College of Obstetricians and Gynaecologists, and the The Royal College of Midwives [2–4]. The ACOG statement received endorsement from the American Academy of Pediatrics [5]; the International Liaison © 2015 Niermeyer. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Niermeyer Maternal Health, Neonatology, and Perinatology (2015) 1:21 Page 2 of 13 Table 1 Targets for further research on physiologic umbilical cord clamping Table 1 Targets for further research on physiologic umbilical cord clamping (Continued) Population Polycythemia Extremely low birth weight/extremely preterm infants Infants with evidence of asphyxia – antepartum/intrapartum Infants born in low-resource settings Intervention (delayed cord clamping with multiple covariates) Term infants and growth-restricted infants Technique-specific differences (delayed clamping vs. umbilical cord milking) Neurodevelopment Antenatal corticosteroid administration before preterm birth Toddler, preschool, elementary school outcomes Type of maternal anesthesia Sex-specific differences Uterine activity (contractions or operative delivery without labor) Correlation with iron status Administration of uterotonic relative to cord clamping Brain microstructure/development (advanced imaging i.e. MRI) Onset of respirations relative to cord clamping Spontaneous Assisted ventilation Position of infant relative to placenta Duration of delay before clamping Behavior Prevalence/duration of exclusive breastfeeding Mortality Maternal obstetrical outcomes Physiologic characteristics postpartum Comparison Postpartum hemorrhage Delay in cord clamping with and without resuscitation Intraoperative complications Initial steps (drying, clearing airway, specific stimulation to breathe) Positive-pressure ventilation Sustained inflation CPAP Intermittent positive-pressure ventilation Umbilical cord milking vs. delayed cord clamping Active milking (length of cord segment, rate, number of passes) Draining of cord segment Outcome Need for resuscitation Physiologic characteristics during postnatal stabilization Temperature Blood pressure Blood glucose Need for volume expanders/pressors (per defined criteria) Committee on Resuscitation recommended delayed cord clamping for infants who do not require immediate resuscitation [6]; and the World Health Organization (WHO) reiterated their recommendation to delay cord clamping for 1–3 min while initiating simultaneous essential newborn care [7]. Still, all current practice guidelines vary slightly in their emphasis and details, and all suggest that delayed cord clamping may not be feasible or desirable in every situation, especially when immediate resuscitation is required. This review will relate recent experimental physiology data to clinical studies, examine the practical dilemmas faced by clinicians, and identify gaps in knowledge as well as directions for further research to more ful (...truncated)