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

Positive end expiratory pressure and respiratory system resistance between self-inflating bag and T-piece resuscitator in a cadaveric piglet lung model

INTRODUCTION

In neonatal resuscitation, T-piece resuscitator (TPR) are used widely, but the evidence is limited for their use in infants born at term gestation. The aim of this study was to compare the delivered positive end expiratory pressure (PEEP) and respiratory system resistance (Rrs) using TPR and self-inflating bag (SIB) in a cadaveric piglet model.

METHODS

Cadaveric newborn piglets were tracheotomised, intubated (cuffed tube) and leak tested. Static lung compliance was measured. Positive pressure ventilation was applied by TPR and SIB in a randomized sequence with varying, inflations per minute (40, 60 and 80 min) and peak inspiratory pressures (18 and 30 cmH₂O). PEEP was constant at 5 cmH₂O. The lungs were washed with saline and static lung compliance was re-measured; ventilation sequences were repeated. Lung inflation data for the respiratory mechanics were measured using a respiratory function monitor and digitally recorded for both pre and post-lung wash inflation sequences. A paired sample t-test was used to compare the mean and standard deviation.

RESULTS

The mean difference in PEEP (TPR vs. SIB) was statistically significant at higher inflation rates of 60 and 80 bpm. At normal lung compliance, mean difference was 1.231 (p = 0.000) and 2.099 (p = 0.000) with PIP of 18 and 30 cmH₂O respectively. Significantly higher Rrs were observed when using a TPR with higher inflation rates of 60 and 80 bpm at varying lung compliance.

CONCLUSION

TPR is associated with significantly higher PEEP in a compliant lung model, which is probably related to the resistance of the TPR circuit. The effect of inadvertent PEEP on lung mechanics and hemodynamics need to be examined in humans. Further studies are needed to assess devices used to provide PEEP (TPR, SIB with PEEP valve, Anaesthetic bag with flow valve) during resuscitation of the newborn.

European Resuscitation Council Guidelines 2021: Newborn resuscitation and support of transition of infants at birth

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

T-piece resuscitator or self-inflating bag during neonatal resuscitation: a scoping review

BACKGROUND

To identify the evidence for administering positive pressure ventilation (PPV) to infants at birth by either T-piece resuscitator (TPR) or self-inflating bag (SIB), and to determine whether a full systematic review (SR) is warranted.

METHODS

Guided by the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for scoping reviews, eligible studies included peer-reviewed human studies, prospectively or retrospectively comparing a TPR vs. SIB for administering PPV at birth. Databases searched were OVID Medline, PubMed, Embase and the Cochrane Central Register of Controlled Trials. Review Manager software was used for the data analysis.

RESULTS

Following electronic literature search and review, data from four eligible studies (3 RCT and 1 observational study), enrolling a total of 2889 patients, were included. Studies differed regarding the investigated populations, reported outcomes and came from different geographical areas. In particular for preterm infants, use of TPR for providing PPV may improve survival, result in fewer intubations at birth and decrease the incidence of bronchopulmonary dysplasia.

CONCLUSIONS

This scoping review identified two new studies with substantive new evidence, pointing towards improved survival, decreased bronchopulmonary dysplasia and fewer intubations at birth, in particular among preterm infants treated with TPR. Full SR of the literature is advised.

IMPACT

This scoping review identified studies comparing TPR vs. SIB for respiratory support of newborn infants previously not included in the International Liaison Committee on Resuscitation (ILCOR) recommendations. Our review found substantive new evidence highlighting that device choice may impact the outcomes of compromised newborn infants'. This scoping review stipulates the need for full SR and updated meta-analysis of studies investigating supportive equipment for stabilizing infants at birth in order to inform ILCOR treatment recommendations.

[Newborn resuscitation and support of transition of infants at birth]

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

Positive End-Expiratory Pressure in Newborn Resuscitation Around Term: A Randomized Controlled Trial

BACKGROUND

International guidelines for resuscitation recommend using positive end-expiratory pressure (PEEP) during ventilation of preterm newborns. Reliable PEEP-valves for self-inflating bags have been lacking, and effects of PEEP during resuscitation of term newborns are insufficiently studied. The objective was to determine if adding a new PEEP valve to the bag-mask during resuscitation of term and near-term newborns could improve heart rate response.

METHODS

This randomized controlled trial was performed at Haydom Lutheran Hospital in Tanzania (September 2016 to June 2018). Helping Babies Breathe-trained midwives performed newborn resuscitation using self-inflating bags with or without a new, integrated PEEP valve. All live-born newborns who received bag-mask ventilation at birth were eligible. Heart rate response measured by ECG was the primary outcome, and clinical outcome and ventilation data were recorded.

RESULTS

Among 417 included newborns (median birth weight 3200 g), 206 were ventilated without and 211 with PEEP. We found no difference in heart rate response. Median (interquartile range) measured PEEP in the PEEP group was 4.7 (2.0-5.6) millibar. The PEEP group received lower tidal volumes (4.9 [1.9-8.2] vs 6.3 [3.9-10.5] mL/kg; P = .02) and had borderline lower expired CO₂ (2.9 [1.5-4.3] vs 3.3 [1.9-5.0] %; P = .05). Twenty four-hour mortality was 9% in both groups.

CONCLUSIONS

We found no evidence for improved heart rate response during bag-mask ventilation with PEEP compared with no PEEP. The PEEP valve delivered a median PEEP within the intended range. The findings do not support routine use of PEEP during resuscitation of newborns around term.