46 e-Letters

published between 2019 and 2022

  • Caution in extrapolating results to first two weeks of life

    I was interested to read this study looking at a question which is extremely important to mothers of preterm infants who need to exclusively express - "how frequently do I need to express?".

    The conclusion that there is no difference in average yield of mothers expressing 5, 6, 7, 8, and 9 times a day will be very useful to mothers who are similar to those included in the study - that is mothers of preterm babies aged at least 10 days (but mostly 15-20 days old), who have good daily expressed milk yield (average yield clustered around 750ml/day for these expressing frequencies). Therefore mothers in this group may feel more confident in reducing their expressing sessions down to a more manageable 5 or 6 per day, which reduces their burden of expressing.

    However it could be harmful to extrapolate outside of these characteristics, for example mothers attempting to establish their supply in the first 2 weeks of life. We know that this period may be a critical window to establish milk supply and this study cannot comment on the relationship of early expressing frequency to the establishment of adequate yield (which, to complicate matters further, is poorly defined in the context of prematurity, with a range of daily volume targets from 500-900ml suggested in the literature and by the Unicef Baby Friendly Initiative). Already I have seen the article summarised as "mothers of preterm infants should express milk at least 5 times a day" on social...

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  • Dr Ilana Levene

    Thank you for this interesting article, which really adds to our understanding of management of neonatal hypoglycaemia. However, your conclusion that a subset of babies should receive formula rather than breastfeed alongside gel, depending on their blood glucose level, is not supported by the evidence you have provided and ignores the potential harm associated with this approach.

    Your data states that alongside the first use of gel, breastfed babies are more likely to require a second gel. There is no literature to support the idea that experiencing a second transient hypoglycaemia in a carefully monitored baby in the first 48 hours of life is harmful (indeed UK guidance uses a treatment threshold of 2mmol/l for the entire first 48 hours of life), and alongside the second gel breastfeeding is as effective as formula so there is no reason to suppose from the data provided that breastfed babies are more likely to go on to require intravenous dextrose.

    Asking breastfeeding mothers to use formula instead of breastfeeding in the first hours of their baby's life is likely to undermine mothers' trust in breastfeeding, may impact on their milk supply through reduced stimulation in the critical time period and reduces the colostrum volume ingested, with its unique immune properties. It is not a recommendation to be made lightly.

  • UK neonatal resuscitation survey - a word of caution

    As authors of the 2015 guidelines we read with interest the “UK neonatal resuscitation survey” [1]. Comparison with 2012 shows a rewarding positive effect of successive guidelines on newborn resuscitation practice.

    However, we wanted to address this statement: “…updated guidelines have been criticised for failing to consider data from the Targeted Oxygen in the Resuscitation of Preterm Infants [To2rpido]”. To2rpido [2], published 2017, was unavailable for inclusion in 2015 ILCOR reviews of evidence. [3]. The analysis referred to was post-hoc and unprespecified. Clinicians were not blinded and recruitment was problematic. Enrolling only 5% of eligible infants, To2rpido was terminated after reaching 15% of targeted sample size due to loss of equipoise: ironically, clinicians were concerned about using high oxygen concentrations.

    Nonetheless, To2rpido generated such interest that it led to the first neonatal review in ILCOR’s continuous evidence evaluation strategy. [4] Utilising GRADE methodology to rate quality of evidence and strength of recommendations, To2rpido’s impact was downgraded because of high risk of bias. This review [4] continues to recommend “starting with a lower oxygen concentration (21–30%) compared to higher oxygen concentration (60–100%)” whilst highlighting many gaps in our current knowledge.

    The use of end-tidal CO2 (ETCO2) detection was not recommended because the guidelines, and Newborn Life Support (NLS) course, focus on airwa...

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  • Methodology concerns about a network meta-analysis

    Dear Editor,
    We read with great interest the network meta-analysis performed by Zeng et al [1]. The authors investigated the comparative efficacy and safety of different corticosteroids in the prevention of bronchopulmonary dysplasia in preterm infants. They included 47 RCTs with 6747 participants. We have several concerns about the study.
    First, it looks that the authors are unfamiliar with the procedures of network meta-analysis because there were obvious mistakes. Figure 1 in the study was network plot of different corticosteroids. In Figure 1, the circle size should be proportional to the sample size randomised to each intervention [2]. The line width should be proportional to the study numbers of each direct comparison. However, the circle size was not proportional to the sample size in Figure 1. The line width between dexamethasone (high dose) and placebo also seems inadequate.
    Second, various statistical methods or plots have been suggested to assist interpreting the results of network meta-analysis [3]. However, many of them were not performed or presented in this study. For example, since there were direct estimates (i.e., results of pairwise meta-analysis) and indirect estimates (i.e., results of network meta-analysis), the inconsistency between them should be assessed and explored because important inconsistency could threaten the validity of the results. Besides, the authors also didn’t assess small-study effects. Small-study effects could mat...

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  • Impact of delivered tidal volume on the occurrence of intraventricular haemorrhage in preterm infants during positive pressure ventilation in the delivery room

    There seems to be a descrepency regarding the number of babies intubatec in two groups. 56 babies were intubated in high tidal volume group against 14 intubated in the low tidal volume group as per the article. I wondering whether it might have contributed to the high incidence of IVH in the high tidal volume group.

  • Delivery of positive end-expiratory pressure to preterm lambs using common resuscitation devices

    I congratulate Dr Thio and colleagues on their study of PEEP delivery in common neonatal resuscitation devices. This study is timely as clinicians look for more refined strategies to support the preterm lung at birth. Such strategies will require a reliance on equipment in the delivery room.
    To allow for interpretation of the findings into the clinical context could the authors comment on the number, and characteristics, of lambs studied, and was this accounted for analysis in Table 1 (for example cluster analysis)? What was the pressure of medical gas supply?