Examining the efficacy of cord clamp delay

In the first seconds of life, a newborn undergoes the transition from fetal to neonatal, which includes the clearing of liquid from airways and changes in the cardiovascular output. The timing of cord clamping is an important step in ensuring the successful transition for the newborn. At the virtual 2021 Pediatric Academic Societies meeting, Georg M. Schmölzer, MD, PhD, neonatologist at the Centre for the Studies of Asphyxia and Resuscitation at the Royal Alexandra Hospital in Edmonton, Alberta, Canada, spoke about the latest recommendations for delayed cord clamping.

Umbilical cord management impacts 130 million infants every year and it impacts the volume of placental transfusion as well as the cardiovascular transition at the onset of breathing. There are a variety of cord management techniques used, including immediate cord clamping, which is clamping in the first 30 seconds of life; delayed clamping, which is clamping after 30 seconds of life; cord milking; or tying the clamp timing to a physiological response like the cessation of cord pulsation. The recommendations for the past decade indicate that cord clamping should be delayed in infants who are breathing and crying. However, if an infant is not breathing or crying, the cord should be clamped so that resuscitation efforts can be started as soon as possible.

The benefits of cord clamping include improved neurodevelopment, a lower incidence of anemia or iron deficiency, and improvements in certain parameters such as cerebral oxygenation. Schmölzer stated that previous research indicated that higher hemoglobin and hematocrit levels in the first 24 hours of life were more likely with delayed cord clamping. A Swedish study that looked at neurodevelopmental outcomes in children who had delayed cord clamping versus early cord clamping showed higher scores across all areas of neurodevelopment, including movement, problem solving, and person-social skills.

Potential risks associated with delaying cord clamping include hypothermia, over-transfusion, jaundice, symptomatic polycythemia, persistent pulmonary hypertension, and delays in resuscitation efforts. However, recent research indicates that there is no increased risk of hyperbilirubinemia with delayed cord clamping. Additionally, a delay in cord clamping was not associated with increased admission to the neonatal intensive care unit. Clinicians should remember, though, that there is no hard and fast rule for delayed cord clamping, and the benefits of doing it with children delivered via cesarean, who were growth restricted, or who are monochorionic twins, remains uncertain.

Schmölzer closed his session with a take-away message that cord clamping should be delayed in infants who are healthy and term. Cord clamping should be delayed at least 60 seconds and can be delayed by as much as 180 seconds in limited-resource environments.

Reference

1. Schmölzer GM. At birth: delayed cord clamping: one size fits all?. Pediatric Academic Societies Meeting 2021; May 1, 2021; virtual. Accessed May 1, 2021.