Respiratory function monitoring to reduce mortality and morbidity in newborn infants receiving resuscitation

Corrective steps to enhance ventilation in the delivery room

OBJECTIVE

The clinical impact of ventilation corrective steps for delivery room positive pressure ventilation (PPV) is not well studied. We aimed to characterise the performance and effect of ventilation corrective steps (MRSOPA (Mask adjustment, Reposition airway, Suction mouth and nose, Open mouth, Pressure increase and Alternative airway)) during delivery room resuscitation of preterm infants.

DESIGN

Prospective observational study of delivery room PPV using video and respiratory function monitor recordings.

SETTING

Tertiary academic delivery hospital.

PATIENTS

Preterm infants <32 weeks gestation.

MAIN OUTCOME MEASURE

Mean exhaled tidal volume (Vte) of PPV inflations before and after MRSOPA interventions, categorised as inadequate (<4 mL/kg); appropriate (4-8 mL/kg), or excessive (>8 mL/kg). Secondary outcomes were leak (>30%) and obstruction (Vte <1 mL/kg), and infant heart rate.

RESULTS

There were 41 corrective interventions in 30 infants, with a median duration of 15 (IQR 7-29) s. The most frequent intervention was a combination of Mask/Reposition and Suction/Open. Mean Vte was inadequate before 16/41 interventions and became adequate following 6/16. Mean Vte became excessive after 6/41 interventions. Mask leak, present before 13/41 interventions, was unchanged after 4 and resolved after 9. Obstruction was present before five interventions and was subsequently resolved only once. MRSOPA interventions introduced leak in two cases and led to obstruction in one case. The heart rate was <100 beats per minute before 31 interventions and rose to >100 beats per minute after 14/31 of these.

CONCLUSIONS

Ventilation correction interventions improve tidal volume delivery in some cases, but lead to ineffective or excessive tidal volumes in others. Mask leak and obstruction can be induced by MRSOPA manoeuvres.

Provider visual attention on a respiratory function monitor during neonatal resuscitation

BACKGROUND

A respiratory function monitor (RFM) provides real-time positive pressure ventilation feedback. Whether providers use RFM during neonatal resuscitation is unknown.

METHODS

Ancillary study to the MONITOR(NCT03256578) randomised controlled trial. Neonatal resuscitation leaders at two centres wore eye-tracking glasses, and visual attention (VA) patterns were compared between RFM-visible and RFM-masked groups.

RESULTS

14 resuscitations (6 RFM-visible, 8 RFM-masked) were analysed. The median total gaze duration on the RFM was significantly higher with a visible RFM (29% vs 1%, p<0.01), while median total gaze duration on other physical objects was significantly lower with a visible RFM (3% vs 8%, p=0.02). Median total gaze duration on the infant was lower with RFM visible, although not statistically significantly (29% vs 46%, p=0.05).

CONCLUSION

Providers' VA patterns differed during neonatal resuscitation when the RFM was visible, emphasising the importance of studying the impact of additional delivery room technology on providers' behaviour.

Predictors for expired CO2 in neonatal bag-mask ventilation at birth: observational study

BACKGROUND

Expired carbon dioxide (ECO2) indicates degree of lung aeration immediately after birth. Favourable ventilation techniques may be associated with higher ECO2 and a faster increase. Clinical condition will however also affect measured values. The aim of this study was to explore the relative impact of ventilation factors and clinical factors on ECO2 during bag-mask ventilation of near-term newborns.

METHODS

Observational study performed in a Tanzanian rural hospital. Side-stream measures of ECO2, ventilation data, heart rate and clinical information were recorded in 434 bag-mask ventilated newborns with initial heart rate <120 beats per minute. We studied ECO2 by clinical factors (birth weight, Apgar scores and initial heart rate) and ventilation factors (expired tidal volume, ventilation frequency, mask leak and inflation pressure) in random intercept models and Cox regression for time to ECO2 >2%.

RESULTS

ECO2 rose non-linearly with increasing expired tidal volume up to >10 mL/kg, and sufficient tidal volume was critical for the time to reach ECO2 >2%. Ventilation frequency around 30/min was associated with the highest ECO2. Higher birth weight, Apgar scores and initial heart rate were weak, but significant predictors for higher ECO2. Ventilation factors explained 31% of the variation in ECO2 compared with 11% for clinical factors.

CONCLUSIONS

Our findings indicate that higher tidal volumes than currently recommended and a low ventilation frequency around 30/min are associated with improved lung aeration during newborn resuscitation. Low ECO2 may be used to identify unfavourable ventilation technique. Clinical factors are also associated with persistently low ECO2 and must be accounted for in the interpretation.

Improving quality of care and outcome at very preterm birth: the Preterm Birth research programme, including the Cord pilot RCT

Background

Being born very premature (i.e. before 32 weeks’ gestation) has an impact on survival and quality of life. Improving care at birth may improve outcomes and parents’ experiences.

Objectives

To improve the quality of care and outcomes following very preterm birth.

Design

We used mixed methods, including a James Lind Alliance prioritisation, a systematic review, a framework synthesis, a comparative review, qualitative studies, development of a questionnaire tool and a medical device (a neonatal resuscitation trolley), a survey of practice, a randomised trial and a protocol for a prospective meta-analysis using individual participant data.

Setting

For the prioritisation, this included people affected by preterm birth and health-care practitioners in the UK relevant to preterm birth. The qualitative work on preterm birth and the development of the questionnaire involved parents of infants born at three maternity hospitals in southern England. The medical device was developed at Liverpool Women’s Hospital. The survey of practice involved UK neonatal units. The randomised trial was conducted at eight UK tertiary maternity hospitals.

Participants

For prioritisation, 26 organisations and 386 individuals; for the interviews and questionnaire tool, 32 mothers and seven fathers who had a baby born before 32 weeks’ gestation for interviews evaluating the trolley, 30 people who had experienced it being used at the birth of their baby (19 mothers, 10 partners and 1 grandmother) and 20 clinicians who were present when it was being used; for the trial, 261 women expected to have a live birth before 32 weeks’ gestation, and their 276 babies.

Interventions

Providing neonatal care at very preterm birth beside the mother, and with the umbilical cord intact; timing of cord clamping at very preterm birth.

Main outcome measures

Research priorities for preterm birth; feasibility and acceptability of the trolley; feasibility of a randomised trial, death and intraventricular haemorrhage.

Review methods

Systematic review of Cochrane reviews (umbrella review); framework synthesis of ethics aspects of consent, with conceptual framework to inform selection criteria for empirical and analytical studies. The comparative review included studies using a questionnaire to assess satisfaction with care during childbirth, and provided psychometric information.

Results

Our prioritisation identified 104 research topics for preterm birth, with the top 30 ranked. An ethnographic analysis of decision-making during this process suggested ways that it might be improved. Qualitative interviews with parents about their experiences of very preterm birth identified two differences with term births: the importance of the staff appearing calm and of staff taking control. Following a comparative review, this led to the development of a questionnaire to assess parents’ views of care during very preterm birth. A systematic overview summarised evidence for delivery room neonatal care and revealed significant evidence gaps. The framework synthesis explored ethics issues in consent for trials involving sick or preterm infants, concluding that no existing process is ideal and identifying three important gaps. This led to the development of a two-stage consent pathway (oral assent followed by written consent), subsequently evaluated in our randomised trial. Our survey of practice for care at the time of birth showed variation in approaches to cord clamping, and that no hospitals were providing neonatal care with the cord intact. We showed that neonatal care could be provided beside the mother using either the mobile neonatal resuscitation trolley we developed or existing equipment. Qualitative interviews suggested that neonatal care beside the mother is valued by parents and acceptable to clinicians. Our pilot randomised trial compared cord clamping after 2 minutes and initial neonatal care, if needed, with the cord intact, with clamping within 20 seconds and initial neonatal care after clamping. This study demonstrated feasibility of a large UK randomised trial. Of 135 infants allocated to cord clamping ≥ 2 minutes, 7 (5.2%) died and, of 135 allocated to cord clamping ≤ 20 seconds, 15 (11.1%) died (risk difference –5.9%, 95% confidence interval –12.4% to 0.6%). Of live births, 43 out of 134 (32%) allocated to cord clamping ≥ 2 minutes had intraventricular haemorrhage compared with 47 out of 132 (36%) allocated to cord clamping ≤ 20 seconds (risk difference –3.5%, 95% CI –14.9% to 7.8%).

Limitations

Small sample for the qualitative interviews about preterm birth, single-centre evaluation of neonatal care beside the mother, and a pilot trial.

Conclusions

Our programme of research has improved understanding of parent experiences of very preterm birth, and informed clinical guidelines and the research agenda. Our two-stage consent pathway is recommended for intrapartum clinical research trials. Our pilot trial will contribute to the individual participant data meta-analysis, results of which will guide design of future trials.

Future work

Research in preterm birth should take account of the top priorities. Further evaluation of neonatal care beside the mother is merited, and future trial of alternative policies for management of cord clamping should take account of the meta-analysis.

Study registration

This study is registered as PROSPERO CRD42012003038 and CRD42013004405. In addition, Current Controlled Trials ISRCTN21456601.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 7, No. 8. See the NIHR Journals Library website for further project information.

Quality Improvement Project to Decrease Delivery Room Intubations in Preterm Infants

BACKGROUND AND OBJECTIVES

Avoidance of delivery room intubation (DRI) reduces death or bronchopulmonary dysplasia (BPD) in preterm neonates. Our objective with this quality improvement project was to decrease DRI rates by improving face mask positive pressure ventilation (Fm-PPV) among infants born ≤29 weeks' gestation.

METHODS

Key drivers of change were identified from a retrospective review of resuscitation records. A resuscitation bundle to optimize Fm-PPV including the use of a small round mask and end-tidal CO₂ detectors, increasing peak inspiratory pressure when indicated, and debriefing after each intubation were implemented in consecutive plan-do-study-act cycles. The DRI rate was tracked by using a control chart. Resuscitation practice and outcomes of pre-quality improvement cohort (QIC) (January 2014-September 2015) were compared with post-QIC (October 2015-December 2016).

RESULTS

Of the 314 infants who were resuscitated, 180 belonged to the pre-QIC and 134 to the post-QIC. The antenatal steroid administration rate was higher in the post-QIC (54% vs 88%). More infants in the post-QIC had resolution of bradycardia after Fm-PPV (56% vs 77%, P = .02). Infants in the post-QIC had lower DRI rates (58% vs 37%, P < .01), lower need for mechanical ventilation (85% vs 70%, P < .01), lower rates of BPD (26% vs 13%, P < .01), and severe retinopathy of prematurity (14% vs 5%, P = .01). Rates of DRI, BPD, and severe retinopathy of prematurity remained lower even after controlling for the potential confounders.

CONCLUSIONS

Implementation of a resuscitation bundle decreased the DRI rate and improved outcomes of preterm infants.

Potential and Limitations of Cochrane Reviews in Pediatric Cardiology: A Systematic Analysis

Evidence-based medicine has contributed substantially to the quality of medical care in pediatric and adult cardiology. However, our impression from the bedside is that a substantial number of Cochrane reviews generate inconclusive data that are of limited clinical benefit. We performed a systematic synopsis of Cochrane reviews published between 2001 and 2015 in the field of pediatric cardiology. Main outcome parameters were the number and percentage of conclusive, partly conclusive, and inconclusive reviews as well as their recommendations and their development over three a priori defined intervals. In total, 69 reviews were analyzed. Most of them examined preterm and term neonates (36.2%), whereas 33.3% included also non-pediatric patients. Leading topics were pharmacological issues (71.0%) followed by interventional (10.1%) and operative procedures (2.9%). The majority of reviews were inconclusive (42.9%), while 36.2% were conclusive and 21.7% partly conclusive. Although the number of published reviews increased during the three a priori defined time intervals, reviews with "no specific recommendations" remained stable while "recommendations in favor of an intervention" clearly increased. Main reasons for missing recommendations were insufficient data (n = 41) as well as an insufficient number of trials (n = 22) or poor study quality (n = 19). There is still need for high-quality research, which will likely yield a greater number of Cochrane reviews with conclusive results.

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.

Noninvasive Monitoring during Interhospital Transport of Newborn Infants

The main indications for interhospital neonatal transports are radiographic studies (e.g., magnet resonance imaging) and surgical interventions. Specialized neonatal transport teams need to be skilled in patient care, communication, and equipment management and extensively trained in resuscitation, stabilization, and transport of critically ill infants. However, there is increasing evidence that clinical assessment of heart rate, color, or chest wall movements is imprecise and can be misleading even in experienced hands. The aim of the paper was to review the current evidence on clinical monitoring equipment during interhospital neonatal transport.