Is delayed cord clamping in preterm infants as safe as immediate clamping regarding 2-years outcomes?

Abstract

Delayed cord clamping (DCC) has already been established in healthy term infants,1 and there is growing evidence that DCC might also have beneficial effects in preterm infants.1-4 Current ERC guidelines recommend DCC for at least 30 seconds in preterm infants who do not need resuscitation.5 So far, approaches of incorporating DCC into stabilisation or resuscitation of preterm infants have not been widely established. However, stabilisation of preterm infants with umbilical cord intact has been described in individual studies2, 3, 6, 7 but long-term follow-up data are scarce. This prospective randomised trial compared DCC after at least 120 seconds and immediate neonatal care with cord intact, with prompt cord clamping within 20 seconds followed by neonatal care, evaluating the survival and neurodevelopmental outcome at two years corrected age. Short-term outcomes of enrolled infants were published separately.7 Initially created as a feasibility study, no formal sample size calculation was done. Neurodevelopmental outcome was assessed by means of Bayley-III Scale and/or parent-completed ASQ-3 questionnaire, if available; otherwise by routine clinical data. Study design aimed at delaying cord clamping for at least 2 minutes and was achieved in 60% of patients.8 This time-based approach of cord clamping contrasts with studies favouring physiological-based cord clamping (PBCC), this fact highlighting the ongoing search for optimal time of clamping.1-3 The study showed a non-significant decrease in the compound measure of mortality or adverse neurodevelopmental outcome in the DCC group. Regarding adverse neurodevelopmental outcome alone there were no differences between the two groups. Despite a tendency towards better outcome at 2 years corrected age in the DCC group, a higher loss to follow-up was observed in infants with poor outcome at discharge in the DCC group. Strengths of the present study include its prospective character, the inclusion of preterm infants and its focus on long-term neurodevelopmental follow-up. However, median GA was 29 weeks in both groups, and only a minority of infants (13%) was born below 26 weeks’ GA.7 Heterogeneity of assessment and classification of neurodevelopmental outcome as well as missing data are important limitations of this study. Overall data were available in 80.7% of cases; valid Bayley-III results exist in nearly half of all infants. The remaining data were assessed by means of ASQ-3 parents' questionnaire potentially lacking objectivity, and in a minority of cases by means of routine clinical data. However, ASQ-3 questionnaires have been evaluated as a screening tool in neonatal neurodevelopmental follow-up.9 In conclusion, this study reported neurodevelopmental outcome at 2 years corrected age in a large proportion of infants. However, assessment was heterogenous and the study was not sufficiently powered to allow for proper analyses of benefits and harms of DCC in preterm infants, thus hampering meaningful conclusions on outcome. Further randomised controlled trials adequately designed and powered to assess short-term and long-term outcomes are needed. https://ebneo.org/2020/03/delayed-cord-clamping-preterm-infants/ None.