Efficacy and user preference of two CO2 detectors in an infant mannequin randomized crossover trial

Expired carbon dioxide during newborn resuscitation as predictor of outcome

AIM

To explore and compare expired CO₂ (ECO₂) and heart rate (HR), during newborn resuscitation with bag-mask ventilation, as predictors of 24-h outcome.

METHODS

Observational study from March 2013 to June 2017 in a rural Tanzanian hospital. Side-stream measures of ECO₂, ventilation parameters, HR, clinical information, and 24-h outcome were recorded in live born bag-mask ventilated newborns with initial HR < 120 bpm. We analysed the data using logistic regression models and compared areas under the receiver operating curves (AUC) for ECO₂ and HR within three selected time intervals after onset of ventilation (0-30 s, 30.1-60 s and 60.1-300 s).

RESULTS

Among 434 included newborns (median birth weight 3100 g), 378 were alive at 24 h, 56 had died. Both ECO₂ and HR were independently significant predictors of 24-h outcome, with no differences in AUCs. In the first 60 s of ventilation, ECO₂ added extra predictive information compared to HR alone. After 60 s, ECO₂ lost significance when adjusted for HR. In 70% of newborns with initial ECO₂ <2% and HR < 100 bpm, ECO₂ reached ≥2% before HR ≥ 100 bpm. Survival at 24 h was reduced by 17% per minute before ECO₂ reached ≥2% and 44% per minute before HR reached ≥100 bpm.

CONCLUSIONS

Higher levels and a faster rise in ECO₂ and HR during newborn resuscitation were independently associated with improved survival compared to persisting low values. ECO₂ increased before HR and may serve as an earlier predictor of survival.

Paediatric exhaled CO2 detector causes leaks

OBJECTIVE

To assess leakage caused by the Pedi-Cap.

METHODS

Bench test I: Pedi-Caps were connected between the Neopuff and a test lung and placed underwater to detect the leak. Bench test II: the disposable Avea VarFlex Flow Transducer measured the leak. Retrospective analysis: recordings of intubations in the delivery room were analysed.

RESULTS

The (rippled) male end of the Pedi-Cap is the origin of the leak. In bench test I, 32% of the Pedi-Caps caused inevitable extensive leaks and 34% caused leaks that diminished after sealing the end. In bench test II (n=44) and the retrospective analysis (n=17), the flow transducer measured 22% (18-60) and 39% (8-82) leakage, respectively. Leakage decreased after removal of the Pedi-Cap (before vs after; 17% (7-75) vs 4% (2-10), p=0.004).

CONCLUSION

The Pedi-Cap causes the leak which can compromise respiratory support. We recommend to remove the Pedi-Cap directly after change of colour and to be cautious when using the device as evaluation tool.

Enhanced monitoring during neonatal resuscitation

Immediately after birth through spontaneous breaths, infants' clear lung liquid replacing it with air, and gradually establishing a functional residual capacity to achieve gas exchange. Most infants start breathing independently after birth and ~3% of infants who require positive pressure ventilation. When newborns fail to start breathing the current neonatal resuscitation guidelines recommend initiatingpositive pressure ventilationusing a face mask and a ventilation device. Adequate ventilation is the cornerstone of successful neonatal resuscitation; therefore, it is mandatory that anybody involved in neonatal resuscitation is trained in mask ventilation techniques. One of the main problems with mask ventilation is that it is very subjective with direct feedback lacking and not uncommonly, the resuscitator does not realise that their technique is unsatisfactory. Many studies have shown that monitoring tidal volume and leak around the mask or endotracheal tube enables the resuscitator to identify the problem and adjust their technique to reduce the leak and deliver and appropriate tidal volume. This chapter discusses the currently available monitoring devices used during stabilization/resuscitation in the delivery room.

Bag Valve Mask Ventilation as a Perceptual-Cognitive Skill

Objective This study used a high-fidelity infant mannequin to examine the relationship between the quality of bag valve mask ventilation (BVMV) and how providers of varying levels of experience use visual feedback (e.g., electronic vital signs) to guide their performance. Background BVMV is a common and critical procedure for managing pediatric respiratory emergencies. However, providers do not consistently deliver effective BVMV. Efforts to improve BVMV have ignored the question of how providers effectively use feedback often available during BVMV. Method Six expert and six novice respiratory therapists completed two simulations of an infant requiring BVMV. In one, the technology failed to display SpO₂, an important but somewhat redundant visual cue. Eye movements, verbal reports, and ventilation rate (in breaths per minute) were measured in each simulation. Results Regardless of SpO₂ availability, eye movements and verbal reports suggested that novices depended strongly on electronic vital signs and when SpO₂ was absent ventilated at a faster rate (exceeding the recommended range of ventilation rates) than when SpO₂ was present. Experts' ventilation rates were comparable and within the recommended range in both conditions. When SpO₂ was absent, experts emphasized information from direct observation of the patient that novices neglected. Conclusion Individual differences in the use of feedback during BVMV contribute to the quality of BVMV. This work bears on the theoretical discussions involving the use of automation and nontechnological cues to guide performance. Application These results have the potential to expand the current understanding of factors underlying effective BVMV with implications for training novice providers.

End user bag-mask ability and perceptions of two infant resuscitation mannequins

AIM

To examine user ability and preference in performing bag-mask ventilation (BMV) with four different configurations of infant mannequins.

METHODS

Participants provided a 30-second period of BMV to a Resusci Baby mannequin (RB), NeoNatalie mannequin (NN), NN filled with air (NNA), NN filled with water (NNW) and NN filled with 50% air and 50% water mix (NNAW). Participants rated the fidelity of each configuration.

RESULTS

Of the 20 participants, 65% rated NNW as having a high level of fidelity (HLF) 'to hold' (50% for NNAW, 10% for RB and 0% for NNA) (p < 0.001). Half rated NNAW as having a HLF in 'tone' (40% for NNW, 20% for RB and 5% for NNA) (p = 0.008). About 45% of participants rated NNAW as having a HLF in 'appearance' (45% for the RB, 20% for NNA and 15% for NNW) (p = 0.035). About 35% of participants rated NNAW as having a HLF in how it 'felt to touch' (30% for NNW, 15% for RB and 10% for NNA) (p = 0.008). Half of participants rated NNAW as having a HLF in terms of 'weight' (45% for NNW, 40% for RB and 0% for NNA) (p = 0.003). Participants delivered the greatest number of effective ventilations to the NNW mannequin.

CONCLUSION

The NNW and NNAW configurations had the highest fidelity and had the highest percentage of effective ventilations delivered.

Quantitative or qualitative carbon dioxide monitoring for manual ventilation: a mannequin study

AIM

To compare the effectiveness of an in-line EtCO2 detector (DET) and a quantitative EtCO2 detector (CAP), both attached to a t-piece resuscitator, during PPV via a face mask.

METHODS

Paediatric trainees were randomly assigned to determine the method of PPV they commenced with (No device (ND), DET or CAP). Participants used each method for 2 min. Participants were video-recorded to determine the amount of effective ventilations delivered with each method.

RESULTS

Twenty-three paediatric trainees provided a total of 6035 ventilations, and 91.2% were deemed effective. The percentages of median effective ventilations with the ND, the DET and the CAP were 91.0%, 93.0% and 94.0%, respectively. Fourteen (61%) of the trainees indicated a preference for the DET method, 8 (35%) for the CAP method, and 1 (4%) of the trainees indicated a preference for the ND method. Capnography was the most effective method per patient.

CONCLUSION

There was no adverse effect with the addition of EtCO2 detectors. Trainees favoured methods of EtCO2 monitoring during ventilation. The NeoStat device was the preferred device by the majority. The greatest efficacy was achieved with the capnography device. Capnography may enhance face mask ventilation.

Pedi-cap color change precedes a significant increase in heart rate during neonatal resuscitation

INTRODUCTION

Heart rate is the most important indicator of infant well-being during neonatal resuscitation. The Nellcor Pedi-Cap turns gold when exposed to exhaled gas with CO₂>15 mmHg. The aim of this study was to determine if Pedi-Cap gold color change during neonatal resuscitation precedes an increase in heart rate in babies with bradycardia receiving mask ventilation.

METHODS

This was a single-center retrospective review of video recordings and physiologic data of newborns with bradycardia receiving mask positive pressure ventilation during neonatal resuscitation. Subjects were included if the baby's HR<100 BPM within the first 90 s of resuscitation. The primary outcome was the change in HR prior to Pedi-Cap gold color change compared to the HR after Pedi-Cap gold color change.

RESULTS

Forty-one newborns during the study period had HR<100 BPM and received mask positive pressure ventilation with a Pedi-Cap. The median heart rate 10s prior to Pedi-Cap gold color change was 75 BPM (IQR 62-85) and increased to 136 BPM (IQR 113-158) 30 s after gold color change (p<0.001). SpO₂ increased from 45 ± 17% prior to Pedi-Cap gold color change to 52 ± 17% 30s after gold color change (p=0.001).

CONCLUSIONS

Colorimetric CO₂ detection during mask positive pressure ventilation in neonatal resuscitation precedes a significant increase in heart rate and SpO₂. The Pedi-Cap can be easily applied during resuscitation, requires no electricity, provides immediate feedback and may be a useful, simple tool early in resuscitation and may be especially useful in resource limited settings.

A review of carbon dioxide monitoring in preterm newborns in the delivery room

INTRODUCTION

The physiologic adaptation to extra uterine life during the immediate neonatal period is unique. Many newborns require assistance in this adaptive process. Recent evidence now supports titrating oxygen to guide resuscitation but no guidance is provided on utilizing exhaled CO2 measurements.

AIM

To review the current evidence relating to the use of CO2 monitoring in preterm newborns in the delivery room.

METHODS

Search was performed using the Cochrane Central Register of Controlled Trials, MEDLINE (1966-2014) and PREMEDLINE, EMBASE (1980-2014), CINAHL (1982-2014), Web of Science (1975-2014) and the Oxford Database of Perinatal Trials.

RESULTS

The search revealed 21 articles relating to CO2 detection, either quantitative or qualitative, in the newborn infant. The majority of these were observational studies, eight relating to CO2 detection as a means of confirming correct endotracheal tube placement in the newborn infant. The other indication is for mask ventilation, and there is one randomized control trial and four observational studies of CO2 detection during mask ventilation. The overall recommendation for CO2 detection for both clinical uses in the delivery suite is level B.

DISCUSSION

CO2 detection may be of particular benefit for preterm infants in the delivery suite. However there is a need for further research into CO2 detection, in particular capnography, as a means of confirming effective PPV in neonatal resuscitation.