Evaluation of respiratory function monitoring at the resuscitation of prematurely born infants

Newborn face mask ventilation training using a standardised intervention and respiratory function monitor: a before and after manikin study

OBJECTIVE

The International Liaison Committee on Resuscitation has recommended improvements in training for neonatal resuscitation, highlighting the potential role of respiratory function monitors (RFMs). Our objective was to determine whether a manikin-based, standardised face mask ventilation training intervention using an RFM with a simple visual display reduced face mask leak.

DESIGN

Multicentre, before and after study. Participants and instructors were blinded to the RFM display during both assessment periods.

PARTICIPANTS

Healthcare professionals working or training in a hospital providing maternity and neonatal services.

INTERVENTION

All participants underwent a training intervention on positive pressure ventilation using a modified, leak-free manikin and RFM. The intervention consisted of a demonstration of optimal face mask ventilation technique, training in RFM interpretation with corrective strategies for common scenarios and a period of deliberate practice. Each participant performed 30 s of positive pressure ventilation blinded to the RFM display before and after training.

MAIN OUTCOME MEASURES

The primary outcome was face mask leak (%) measured after training. Secondary outcome measures included expired tidal volume, inflating pressures and ventilation rate. Adjustments made to technique during training were an important qualitative outcome.

RESULTS

Four hundred and fourteen participants were recruited over a 13-month period from April 2022, and 412 underwent analysis. Median (IQR) face mask leak before training was 31% (10-69%) compared with 10% (6-18%) after training (p<0.0001). Improvements were noted across all other ventilation parameters.

CONCLUSION

Standardised face mask ventilation training using an RFM with simple visual feedback led to a significant reduction in leak.

The newborn delivery room of tomorrow: emerging and future technologies

Advances in neonatal care have resulted in improved outcomes for high-risk newborns with technologies playing a significant part although many were developed for the neonatal intensive care unit. The care provided in the delivery room (DR) during the first few minutes of life can impact short- and long-term neonatal outcomes. Increasingly, technologies have a critical role to play in the DR particularly with monitoring and information provision. However, the DR is a unique environment and has major challenges around the period of foetal to neonatal transition that need to be overcome when developing new technologies. This review focuses on current DR technologies as well as those just emerging and further over the horizon. We identify what key opinion leaders in DR care think of current technologies, what the important DR measures are to them, and which technologies might be useful in the future. We link these with key technologies including respiratory function monitors, electoral impedance tomography, videolaryngoscopy, augmented reality, video recording, eye tracking, artificial intelligence, and contactless monitoring. Encouraging funders and industry to address the unique technological challenges of newborn care in the DR will allow the continued improvement of outcomes of high-risk infants from the moment of birth. IMPACT: Technological advances for newborn delivery room care require consideration of the unique environment, the variable patient characteristics, and disease states, as well as human factor challenges. Neonatology as a speciality has embraced technology, allowing its rapid progression and improved outcomes for infants, although innovation in the delivery room often lags behind that in the intensive care unit. Investing in new and emerging technologies can support healthcare providers when optimising care and could improve training, safety, and neonatal outcomes.

Early origins of respiratory disease

Chronic respiratory morbidity is unfortunately common in childhood, particularly in those born very prematurely or with congenital anomalies affecting pulmonary development and those with sickle cell disease. Our research group, therefore, has focused on the early origins of chronic respiratory disease. This has included assessing antenatal diagnostic techniques and potentially therapeutic interventions in infants with congenital diaphragmatic hernia. Undertaking physiological studies, we have increased the understanding of the premature baby's response to resuscitation and evaluated interventions in the delivery suite. Mechanical ventilation modes have been optimised and randomised controlled trials (RCTs) with short- and long-term outcomes undertaken. Our studies highlighted respiratory syncytial virus lower respiratory tract infections (LRTIs) and other respiratory viral LRTIs had an adverse impact on respiratory outcomes of prematurely born infants, who we demonstrated have a functional and genetic predisposition to respiratory viral LRTIs. We have described the long-term respiratory outcomes for children with sickle cell disease and importantly identified influencing factors. In conclusion, it is essential to undertake long term follow up of infants at high risk of chronic respiratory morbidity if effective preventative strategies are to be developed.

Resuscitators' opinions on using a respiratory function monitor during neonatal resuscitation

AIM

The aim of this study was to assess the resuscitators' opinions of the usefulness and clinical value of using a respiratory function monitor (RFM) when resuscitating extremely preterm infants with positive pressure ventilation.

METHODS

The link to an online survey was sent to 106 resuscitators from six countries who were involved in a multicentre trial that compared the percentage of inflations within a predefined target range with and without the RFM. The resuscitators were asked to assess the usefulness and clinical value of the RFM. The survey was online for 4 months after the trial ended in May 2019.

RESULTS

The survey was completed by 74 (70%) resuscitators of which 99% considered the RFM to be helpful during neonatal resuscitation and 92% indicated that it influenced their decision-making. The majority (76%) indicated that using the RFM improved their practice and made resuscitation more effective, even when the RFM was not available. Inadequate training was the key issue that limited the effectiveness of the RFM: 45% felt insufficiently trained, and 78% felt more training in using and interpreting the RFM would have been beneficial.

CONCLUSION

Resuscitators considered the RFM to be helpful to guide neonatal resuscitation, but sufficient training was required to achieve the maximum benefit.

Respiratory function monitoring to improve the outcomes following neonatal resuscitation: a systematic review and meta-analysis

IMPORTANCE

Animal and observational human studies report that delivery of excessive tidal volume (V_T) at birth is associated with lung and brain injury. Using a respiratory function monitor (RFM) to guide V_T delivery might reduce injury and improve outcomes.

OBJECTIVE

To determine whether use of an RFM in addition to clinical assessment versus clinical assessment alone during mask ventilation in the delivery room reduces in-hospital mortality and morbidity of infants <37 weeks' gestation.

STUDY SELECTION

Randomised controlled trials (RCTs) comparing RFM in addition to clinical assessment versus clinical assessment alone during mask ventilation in the delivery room of infants born <37 weeks' gestation.

DATA ANALYSIS

Risk of bias was assessed using Covidence Collaboration tool and pooled into a meta-analysis using a random-effects model. The primary outcome was death prior to discharge.

MAIN OUTCOME

Death before hospital discharge.

RESULTS

Three RCTs enrolling 443 infants were combined in a meta-analysis. The pooled analysis showed no difference in rates of death before discharge with an RFM versus no RFM, relative risk (RR) 95% (CI) 0.98 (0.64 to 1.48). The pooled analysis suggested a significant reduction for brain injury (a combination of intraventricular haemorrhage and periventricular leucomalacia) (RR 0.65 (0.48 to 0.89), p=0.006) and for intraventricular haemorrhage (RR 0.69 (0.50 to 0.96), p=0.03) in infants receiving positive pressure ventilation with an RFM versus no RFM.

CONCLUSION

In infants <37 weeks, an RFM in addition to clinical assessment compared with clinical assessment during mask ventilation resulted in similar in-hospital mortality, significant reduction for any brain injury and intraventricular haemorrhage. Further trials are required to determine whether RFMs should be routinely available for neonatal resuscitation.

Technology in the delivery room supporting the neonatal healthcare provider's task

Very preterm infants are a unique and highly vulnerable group of patients that have a narrow physiological margin within which interventions are safe and effective. The increased understanding of the foetal to neonatal transition marks the intricacy of the rapid and major physiological changes that take place, making delivery room stabilisation and resuscitation an increasingly complex and sophisticated activity for caregivers to perform. While modern, automated technologies are progressively implemented in the neonatal intensive care unit (NICU) to enhance the caregivers in providing the right care for these patients, the technology in the delivery room still lags far behind. Diligent translation of well-known and promising technological solutions from the NICU to the delivery room will allow for better support of the caregivers in performing their tasks. In this review we will discuss the current technology used for stabilisation of preterm infants in the delivery room and how this could be optimised in order to further improve care and outcomes of preterm infants in the near future.

Lung Protection During Mechanical Ventilation in the Premature Infant

Mechanical ventilation can be life-saving for the premature infant, but is often injurious to immature and underdeveloped lungs. Lung injury is caused by atelectrauma, oxygen toxicity, and volutrauma. Lung protection must include appropriate lung recruitment starting in the delivery suite and throughout mechanical ventilation. Strategies include open lung ventilation, positive end-expiratory pressure, and volume-targeted ventilation. Respiratory function monitoring, such as capnography and ventilator graphics, provides clinicians with continuous real-time information and an adjunct to optimize lung-protective ventilatory strategies. Further research is needed to assess which lung-protective strategies result in a decrease in long-term respiratory morbidity.

Tools to assess lung aeration in neonates with respiratory distress syndrome

AIM

Respiratory distress syndrome is a common condition among preterm neonates, and assessing lung aeration assists in diagnosing the disease and helping to guide and monitor treatment. We aimed to identify and analyse the tools available to assess lung aeration in neonates with respiratory distress syndrome.

METHODS

A systematic review and narrative synthesis of studies published between January 1, 2004, and August 26, 2019, were performed using the OVID Medline, PubMed, Embase and Scopus databases.

RESULTS

A total of 53 relevant papers were retrieved for the narrative synthesis. The main tools used to assess lung aeration were respiratory function monitoring, capnography, chest X-rays, lung ultrasound, electrical impedance tomography and respiratory inductive plethysmography. This paper discusses the evidence to support the use of these tools, including their advantages and disadvantages, and explores the future of lung aeration assessments within neonatal intensive care units.

CONCLUSION

There are currently several promising tools available to assess lung aeration in neonates with respiratory distress syndrome, but they all have their limitations. These tools need to be refined to facilitate convenient and accurate assessments of lung aeration in neonates with respiratory distress syndrome.

End-tidal carbon dioxide levels during resuscitation and carbon dioxide levels in the immediate neonatal period and intraventricular haemorrhage

Abnormal levels of end-tidal carbon dioxide (EtCO₂) during resuscitation in the delivery suite are associated with intraventricular haemorrhage (IVH) development. Our aim was to determine whether carbon dioxide (CO₂) levels in the first 3 days after birth reflected abnormal EtCO₂ levels in the delivery suite, and hence, a prolonged rather than an early insult resulted in IVH. In addition, we determined if greater EtCO₂level fluctuations during resuscitation occurred in infants who developed IVH. EtCO₂ levels during delivery suite resuscitation and CO₂ levels on the neonatal unit were evaluated in 58 infants (median gestational age 27.3 weeks). Delta EtCO₂ was the difference between the highest and lowest level of EtCO₂. Thirteen infants developed a grade 3-4 IVH (severe group). There were no significant differences in CO₂ levels between those who did and did not develop an IVH (or severe IVH) on the NICU. The delta EtCO₂ during resuscitation differed between infants with any IVH (6.2 (5.4-7.5) kPa) or no IVH (3.8 (2.7-4.3) kPA) (p < 0.001) after adjusting for differences in gestational age. Delta EtCO₂ levels gave an area under the ROC curve of 0.940 for prediction of IVH.Conclusion: The results emphasize the importance of monitoring EtCO₂ levels in the delivery suite.What is Known:• Abnormal levels of carbon dioxide (CO₂) in the first few days after birth and abnormal end-tidal CO₂levels (EtCO₂) levels during resuscitation are associated in preterm infants with the risk of developing intraventricular haemorrhage (IVH).What is New:• There were no significant differences in NICU CO₂levels between those who developed an IVH or no IVH.• There was a poor correlation between delivery suite ETCO₂levels and NICU CO₂levels.• Large fluctuations in EtCO₂during resuscitation in the delivery suite were highly predictive of IVH development in preterm infants.

Respiratory monitors to teach newborn facemask ventilation: a randomised trial

OBJECTIVE

The International Liaison Committee on Resuscitation has found that there is a need for high-quality randomised trials of training interventions that improve the effectiveness of resuscitation skills. The objective of this study was to determine whether using a respiratory function monitor (RFM) during mask ventilation training with a manikin reduces facemask leak.

DESIGN

Stratified, parallel-group, randomised controlled trial. Outcome assessors were blinded to group allocation.

SETTING

Thirteen hospitals in Australia, including non-tertiary sites.

PARTICIPANTS

Consecutive sample of healthcare professionals attending a structured newborn resuscitation training course.

INTERVENTIONS

An RFM providing real-time, objective, leak, flow and volume information was attached to the facemask during 1.5 hours of newborn ventilation and simulation training using a manikin. Participants were randomised to have the RFM display visible (intervention) or masked (control), using a computer-generated randomisation sequence.

MAIN OUTCOME MEASURES

The primary outcome was facemask leak measured after neonatal facemask ventilation training. Tidal volume was an important secondary outcome measure.

RESULTS

Participants were recruited from May 2016 to November 2017. Of 402 eligible participants, two refused consent. Four hundred were randomised, 200 to each group, of whom 194 in each group underwent analysis. The median (IQR) facemask leak was 23% (8%-41%) in the RFM visible group compared with 35% (14%-67%) in the masked group, p<0.0001, difference (95% CI) in medians 12 (4 to 22).

CONCLUSIONS

The display of information from an RFM improved the effectiveness of newborn facemask ventilation training.

TRIAL REGISTRATION NUMBER

ACTRN12616000542493, pre-results.

Tidal volume monitoring during initial resuscitation of extremely prematurely born infants

Background Airway obstruction can occur during facemask (FM) resuscitation of preterm infants at birth. Intubation bypasses any upper airway obstruction. Thus, it would be expected that the occurrence of low expiratory tidal volumes (VTes) would be less in infants resuscitated via an endotracheal tube (ETT) rather than via an FM. Our aim was to test this hypothesis. Methods Analysis was undertaken of respiratory function monitoring traces made during initial resuscitation in the delivery suite to determine the peak inflating pressure (PIP), positive end expiratory pressure (PEEP), the VTe and maximum exhaled carbon dioxide (ETCO2) levels and the number of inflations with a low VTe (less than 2.2 mL/kg). Results Eighteen infants were resuscitated via an ETT and 11 via an FM, all born at less than 29 weeks of gestation. Similar inflation pressures were used in both groups (17.2 vs. 18.8 cmH2O, P = 0.67). The proportion of infants with a low median VTe (P = 0.6) and the proportion of inflations with a low VTe were similar in the groups (P = 0.10), as was the lung compliance (P = 0.67). Infants with the lowest VTe had the stiffest lungs (P < 0.001). Conclusion Respiratory function monitoring during initial resuscitation can objectively identify infants who may require escalation of inflation pressures.

UK neonatal resuscitation survey

BACKGROUND

Previous surveys have demonstrated that neonatal resuscitation practices on the delivery suite vary between UK units, particularly according to the hospital's neonatal unit's level. Our aim was to determine if recent changes to the Resuscitation Council guidelines had influenced clinical practice.

METHODS

Surveys of resuscitation practices at UK delivery units carried out in 2012 and 2017 were compared.

RESULTS

Comparing 2017 with 2012, initial resuscitation using air was more commonly used in both term (98% vs 75%, p<0.001) and preterm (84% vs 34%, p<0.001) born infants. Exhaled carbon dioxide monitoring was more frequently employed in 2017 (84% vs 19%, p<0.001). There were no statistically significant differences in practices according to the level of neonatal care provided by the hospital.

CONCLUSION

There have been significant changes in neonatal resuscitation practices in the delivery suite since 2012 regardless of the different levels of neonatal care offered.

Visual attention on a respiratory function monitor during simulated neonatal resuscitation: an eye-tracking study

OBJECTIVE

A respiratory function monitor (RFM) may improve positive pressure ventilation (PPV) technique, but many providers do not use RFM data appropriately during delivery room resuscitation. We sought to use eye-tracking technology to identify RFM parameters that neonatal providers view most commonly during simulated PPV.

DESIGN

Mixed methods study. Neonatal providers performed RFM-guided PPV on a neonatal manikin while wearing eye-tracking glasses to quantify visual attention on displayed RFM parameters (ie, exhaled tidal volume, flow, leak). Participants subsequently provided qualitative feedback on the eye-tracking glasses.

SETTING

Level 3 academic neonatal intensive care unit.

PARTICIPANTS

Twenty neonatal resuscitation providers.

MAIN OUTCOME MEASURES

Visual attention: overall gaze sample percentage; total gaze duration, visit count and average visit duration for each displayed RFM parameter. Qualitative feedback: willingness to wear eye-tracking glasses during clinical resuscitation.

RESULTS

Twenty providers participated in this study. The mean gaze sample captured wa s 93% (SD 4%). Exhaled tidal volume waveform was the RFM parameter with the highest total gaze duration (median 23%, IQR 13-51%), highest visit count (median 5.17 per 10 s, IQR 2.82-6.16) and longest visit duration (median 0.48 s, IQR 0.38-0.81 s). All participants were willing to wear the glasses during clinical resuscitation.

CONCLUSION

Wearable eye-tracking technology is feasible to identify gaze fixation on the RFM display and is well accepted by providers. Neonatal providers look at exhaled tidal volume more than any other RFM parameter. Future applications of eye-tracking technology include use during clinical resuscitation.

Detection of exhaled carbon dioxide following intubation during resuscitation at delivery

OBJECTIVES

End tidal carbon dioxide (ETCO₂) monitoring can facilitate identification of successful intubation. The aims of this study were to determine the time to detect ETCO₂ following intubation during resuscitation of infants born prematurely and whether it differed according to maturity at birth or the Apgar scores (as a measure of the infant's condition after birth).

DESIGN

Analysis of recordings of respiratory function monitoring.

SETTING

Two tertiary perinatal centres.

PATIENTS

Sixty-four infants, with median gestational age of 27 (range 23-34)weeks.

INTERVENTIONS

Respiratory function monitoring during resuscitation in the delivery suite.

MAIN OUTCOME MEASURES

The time following intubation for ETCO₂ levels to be initially detected and to reach 4 mm Hg and 15 mm Hg.

RESULTS

The median time for initial detection of ETCO₂ following intubation was 3.7 (range 0-44) s, which was significantly shorter than the median time for ETCO₂ to reach 4 mm Hg (5.3 (range 0-727) s) and to reach 15 mm Hg (8.1 (range 0-827) s) (both P<0.001). There were significant correlations between the time for ETCO₂ to reach 4 mm Hg (r=-0.44, P>0.001) and 15 mm Hg (r=-0.48, P<0.001) and gestational age but not with the Apgar scores.

CONCLUSIONS

The time for ETCO₂ to be detected following intubation in the delivery suite is variable emphasising the importance of using clinical indicators to assess correct endotracheal tube position in addition to ETCO₂ monitoring. Capnography is likely to detect ETCO₂ faster than colorimetric devices.

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

BACKGROUND AND OBJECTIVES

Delivery of inadvertent high tidal volume (V_T) during positive pressure ventilation (PPV) in the delivery room is common. High V_T delivery during PPV has been associated with haemodynamic brain injury in animal models. We examined if V_T delivery during PPV at birth is associated with brain injury in preterm infants <29 weeks' gestation.

METHODS

A flow-sensor was placed between the mask and the ventilation device. V_T values were compared with recently described reference ranges for V_T in spontaneously breathing preterm infants at birth. Infants were divided into two groups: V_T<6  mL/kg or V_T>6 mL/kg (normal and high V_T, respectively). Brain injury (eg, intraventricular haemorrhage (IVH)) was assessed using routine ultrasound imaging within the first days after birth.

RESULTS

A total of 165 preterm infants were included, 124 (75%) had high V_T and 41 (25%) normal V_T. The mean (SD) gestational age and birth weight in high and normal V_T group was similar, 26 (2) and 26 (1) weeks, 858 (251) g and 915 (250) g, respectively. IVH in the high V_T group was diagnosed in 63 (51%) infants compared with 5 (13%) infants in the normal V_T group (P=0.008).Severe IVH (grade III or IV) developed in 33/124 (27%) infants in the high V_T group and 2/41 (6%) in the normal V_T group (P=0.01).

CONCLUSIONS

High V_T delivery during mask PPV at birth was associated with brain injury. Strategies to limit V_T delivery during mask PPV should be used to prevent high V_T delivery.

Relationship of resuscitation, respiratory function monitoring data and outcomes in preterm infants

Intraventricular haemorrhage (IVH) and bronchopulmonary dysplasia (BPD) are major complications of premature birth. We tested the hypotheses that prematurely born infants who developed an IVH or BPD would have high expiratory tidal volumes (V_TE) (V_TE > 6 ml/kg) and/or low-end tidal carbon dioxide (ETCO₂) levels (ETCO₂ levels < 4.5 kPa) as recorded by respiratory function monitoring or hyperoxia (oxygen saturation (SaO₂) > 95%) during resuscitation in the delivery suite. Seventy infants, median gestational age 27 weeks (range 23-33), were assessed; 31 developed an IVH and 43 developed BPD. Analysis was undertaken of 31,548 inflations. The duration of resuscitation did not differ significantly between the groups. Those who developed an IVH compared to those who did not had a greater number of inflations with a high V_TE and a low ETCO₂, which remained significant after correcting for differences in gestational age and birth weight between groups (p = 0.019). Differences between infants who did and did not develop BPD were not significant after correcting for differences in gestational age and birth weight. There were no significant differences in the duration of hyperoxia between the groups.Conclusions: Avoidance of high tidal volumes and hypocarbia in the delivery suite might reduce IVH development. What is known • Hypocarbia on the neonatal unit is associated with the development of intraventricular haemorrhage (IVH) and bronchopulmonary dysplasia (BPD). What is new • Infants who developed an IVH compared to those who did not had significantly more inflations with high expiratory tidal volumes and low ETCO₂s.

A Randomized Controlled Trial of End-Tidal Carbon Dioxide Detection of Preterm Infants in the Delivery Room

OBJECTIVE

To compare the ability of qualitative versus quantitative methods of end-tidal carbon dioxide (EtCO₂) detection to maintain normocarbia during face mask ventilation (FMV) of preterm infants (<32 weeks) in the delivery room.

STUDY DESIGN

Preterm infants <32 weeks were randomly assigned to the use of a disposable PediCap EtCO₂ detector (Covidien, Dublin, Ireland) (qualitative) or a Microstream side stream capnography device (Covidien) (quantitative) for FMV in the delivery room, via a NeoPuff T-piece resuscitator (Fisher and Paykel, Auckland, New Zealand). The primary outcome was the presence of normocarbia, based on partial pressure of CO₂ (PaCO₂) readings obtained in the neonatal intensive care unit within an hour of birth. Normocarbia was defined as a PaCO₂ measure between 37.5 and 60 mm Hg (5-8 kPa).

RESULTS

Of the 59 infants included, 59% (35/59) were within the PaCO₂ target range within an hour of birth. There was no difference in the primary outcome; 64% (21/33) of infants in the quantitative group were within the PaCO₂ range compared with 54% (14/26) in the qualitative group (P = .594); and 93% of participants <28 weeks' gestation were within the PaCO₂ normocarbic range (90% [9/10] in quantitative group and 100% [5/5] in the qualitative group [P = 1]). There was no difference in the intubation rate, days of ventilation, or bronchopulmonary dysplasia rates between the 2 groups.

CONCLUSIONS

Quantitative or qualitative EtCO₂ detection methods are both feasible for FMV in the delivery room. Although there was no difference in the incidence of normocarbia, the use of either form of EtCO₂ monitoring should be considered during newborn stabilization, especially in infants less than 28 weeks' gestation.

TRIAL REGISTRATION

ISRCTN: ISRCTN10934870.

Enhanced Monitoring of the Preterm Infant during Stabilization in the Delivery Room

Monitoring of preterm infants in the delivery room (DR) remains limited. Current guidelines suggest that pulse oximetry should be available for all preterm infant deliveries, and that if intubated a colorimetric carbon dioxide detector should provide verification of correct endotracheal tube placement. These two methods of assessment represent the extent of objective monitoring of the newborn commonly performed in the DR. Monitoring non-invasive ventilation effectiveness (either by capnography or respiratory function monitoring) and cerebral oxygenation (near-infrared spectroscopy) is becoming more common within research settings. In this article, we will review the different modalities available for cardiorespiratory and neuromonitoring in the DR and assess the current evidence base on their feasibility, strengths, and limitations during preterm stabilization.

Accuracy of currently available neonatal respiratory function monitors for neonatal resuscitation

This study aimed to test the accuracy in volume measurements of three available respiratory function monitors (RFMs) for neonatal resuscitation and the effect of changing gas conditions. The Florian, New Life Box Neo-RSD (NLB Neo-RSD) and NICO RFM were tested on accuracy with volumes of 10 and 20 mL and on changes in volume measurements under changing gas conditions (oxygen level 21-100 % and from cold dry air (24 ± 2 °C) to heated humidified air (37 °C). Volume differences >10 % were considered clinically relevant. We found that the mean (SD) volume difference was clinically acceptable for all devices (10, 20 mL): Florian (+8.4 (1.2)%, +8.4 (0.5)%); NLB Neo-RSD (+5.8 (1.1)%, +4.3 (1.4)%); and NICO (-8.2 (0.9)%, -8.7 (0.8)%). Changing from cold dry to heated humidified air increased the volume difference using the Florian (cold dry air, heated humidified air (+5.2 (1.2)%, +12.2 (0.9)%) but not NLB Neo-RSD (+2.0(1.6)%, +3.4(2.8)%) and NICO (-2.3 % (0.8), +0.1 (0.6)%). Similarly, when using heated humidified air, increasing oxygen enlarged increased the volume difference using the Florian (oxygen 21 %, 100 %: +12.2(1.0)%, +19.8(1.1)%), but not NLB Neo-RSD (+0.2(1.9)%, +1.1(2.8)%) and NICO (-5.6(0.9)%, -3.7(0.9)%). Clinically relevant changes occurred when changing both gas conditions (Florian +25.7(1.7)%; NLB Neo-RSD +3.8(2.4)%; NICO -5.7(1.4)%).

CONCLUSION

The available RFMs demonstrated clinically acceptable deviations in volume measurements, except for the Florian when changing gas conditions.

WHAT IS KNOWN

•Respiratory function monitors (RFMs) are increasingly used for volume measurements during respiratory support of infants at birth. •During respiratory support at birth, gas conditions can change quickly, which can influence the volume measurements. What is new: •The available RFMs have clinically acceptable deviations when measuring the accuracy of volume measurements. •The RFM using a hot wire anemometer demonstrated clinically relevant deviations in volume measurements when changing the gas conditions. These deviations have to be taken into account when interpreting the volumes directly at birth.

Unraveling the Links Between the Initiation of Ventilation and Brain Injury in Preterm Infants

The initiation of ventilation in the delivery room is one of the most important but least controlled interventions a preterm infant will face. Tidal volumes (V T) used in the neonatal intensive care unit are carefully measured and adjusted. However, the V Ts that an infant receives during resuscitation are usually unmonitored and highly variable. Inappropriate V Ts delivered to preterm infants during respiratory support substantially increase the risk of injury and inflammation to the lungs and brain. These may cause cerebral blood flow instability and initiate a cerebral inflammatory cascade. The two pathways increase the risk of brain injury and potential life-long adverse neurodevelopmental outcomes. The employment of new technologies, including respiratory function monitors, can improve and guide the optimal delivery of V Ts and reduce confounders, such as leak. Better respiratory support in the delivery room has the potential to improve both respiratory and neurological outcomes in this vulnerable population.