Physiological-based cord clamping in very preterm infants: the Aeration, Breathing, Clamping 3 (ABC3) trial—study protocol for a multicentre randomised controlled trial

Ronny Knol*, Emma Brouwer, Thomas van den Akker, Philip L.J. DeKoninck, Enrico Lopriore, Wes Onland, Marijn J. Vermeulen, M. Elske van den Akker–van Marle, Leti van Bodegom–Vos, Willem P. de Boode, Anton H. van Kaam, Irwin K.M. Reiss, Graeme R. Polglase, G. Jeroen Hutten, Sandra A. Prins, Estelle E.M. Mulder, Christian V. Hulzebos, Sam J. van Sambeeck, Mayke E. van der Putten, Inge A. ZonnenbergStuart B. Hooper, Arjan B. te Pas

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

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Background: International guidelines recommend delayed umbilical cord clamping (DCC) up to 1 min in preterm infants, unless the condition of the infant requires immediate resuscitation. However, clamping the cord prior to lung aeration may severely limit circulatory adaptation resulting in a reduction in cardiac output and hypoxia. Delaying cord clamping until lung aeration and ventilation have been established (physiological-based cord clamping, PBCC) allows for an adequately established pulmonary circulation and results in a more stable circulatory transition. The decline in cardiac output following time-based delayed cord clamping (TBCC) may thus be avoided. We hypothesise that PBCC, compared to TBCC, results in a more stable transition in very preterm infants, leading to improved clinical outcomes. The primary objective is to compare the effect of PBCC on intact survival with TBCC. Methods: The Aeriation, Breathing, Clamping 3 (ABC3) trial is a multicentre randomised controlled clinical trial. In the interventional PBCC group, the umbilical cord is clamped after the infant is stabilised, defined as reaching heart rate > 100 bpm and SpO2 > 85% while using supplemental oxygen < 40%. In the control TBCC group, cord clamping is time based at 30–60 s. The primary outcome is survival without major cerebral and/or intestinal injury. Preterm infants born before 30 weeks of gestation are included after prenatal parental informed consent. The required sample size is 660 infants. Discussion: The findings of this trial will provide evidence for future clinical guidelines on optimal cord clamping management in very preterm infants at birth. Trial registration: NCT03808051. First registered on January 17, 2019.

Original languageEnglish
Article number838
Issue number1
Publication statusPublished - 1 Oct 2022

Bibliographical note

Funding Information:
The trial is funded by The Netherlands Organisation for Health Research and Development (project number 852001902). AtP is a recipient of an NWO innovational research incentives scheme (VIDI 91716428). RK received a grant from the Sophia Children’s Hospital Foundation (Rotterdam, S17-14). This project was sponsored by the Gisela Thier Fund (Leiden).

Publisher Copyright: © 2022, The Author(s).


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