Relationship between oscillatory volume and oscillatory pressure in neonatal high-frequency oscillatory ventilators: an in vitro study

OBJECTIVE

We analysed the relationship between oscillatory volume (VOSC) and pressure amplitude (ΔP) in six neonatal high-frequency oscillatory (HFO) ventilators and related it to (1) the accuracy of VOSC and ΔP measurements and (2) the maximal delivered ΔP.

DESIGN

In vitro study.

SETTING

Neonatal intensive care unit.

INTERVENTIONS

Ventilators tested were VN800 (Dräger), Servo-n (Maquet Getinge), SensorMedics 3100A (Vyaire Medical), Fabian HFOi (Vyaire Medical), SLE6000 (SLE UK) and Humming Vue (Metran). We changed various settings and mechanical characteristics of the test lung to mimic preterm and term conditions.

MAIN OUTCOME MEASURES

For each condition, we measured VOSC and ΔP. We assessed the accuracy of the VOSC and ΔP measurements versus a reference measurement system using linear regression and Bland-Altman analysis. We evaluated the maximum delivered ΔP at different oscillatory frequencies.

RESULTS

We observed large variability between machines in the ΔP displayed at any target VOSC. Most ventilators over-read ΔP with errors up to 30 cmH2O or 60%. The error in the measurement of VOSC was up to ±2 mL or ±30%. We observed high variability in the accuracy of ΔP and VOSC measurements; the SLE6000 committed the lowest errors in ΔP measurements and the Fabian HFOi in VOSC. The maximum delivered ΔP varied depending on the ventilator, being maximal for the Humming Vue, followed by the SLE6000 and SensorMedics 3100A.

CONCLUSIONS

The variability in the relationship between VOSC and ΔP among HFO ventilators is largely explained by the variable accuracy in ΔP and VOSC measurement. Different ventilators also exhibit important differences in the maximal generated ΔP.

Asthma, classical conditioning, and the autonomic nervous system - a hypothesis for why children wheeze

Paediatric asthma is an increasing global healthcare problem for which current treatments are not always effective. This review explores how abnormal triggering of the autonomic diving reflex might be important in explaining research findings and the real-world experience of asthma. It hypothesises that the way in which stress during pregnancy is associated with childhood asthma could be through effects on the developing nervous system. This results in increased parasympathetic responsiveness and specifically, excessive triggering of the diving reflex in response to wetting and cooling of the face and nose as occurs with upper airway infections and allergic rhinitis. In aquatic mammals the reflex importantly includes the contraction of airway smooth muscle to minimise lung volume and prevent nitrogen narcosis from diving at depth. Misfiring of this reflex in humans could result in the pathological airway narrowing that occurs in asthma. The diving reflex, and possibly also smooth muscle, is a vestigial remnant of our aquatic past. The hypothesis further suggests that classically conditioned reflex responses to neutral cues and contexts that were present at the same time as the stimuli that initially caused symptoms, become of themselves ongoing triggers of recurrent wheeze. Symptoms occurring in this way, irrespective of the presence of allergens and ongoing airway sensitisation, explain why allergen avoidance is poorly effective in alleviating wheeze and why asthma is made worse by stress. Interventions to suppress the diving reflex and to prevent reflex conditioned wheezing could result in more effective asthma management.

Stepwise genetic approach for the diagnosis of primary ciliary dyskinesia in highly consanguineous populations

BACKGROUND

The American Thoracic Society guidelines for the diagnosis of primary ciliary dyskinesia (PCD) consider the presence of a bi-allelic pathogenic variant confirmatory for the diagnosis of PCD, with genetic testing recommended when other confirmatory diagnostic tests are less accessible. We present our experience with genetic testing as first line with a proposed algorithm for high consanguinity populations.

METHODS

Patients with a suspected diagnosis of PCD underwent genetic testing according to a diagnostic algorithm composed of three steps: (1) patients with a previously known causative familial/Bedouin tribal pathogenic variant completed direct testing for a single variant; (2) if the initial test was negative or there was no known pathogenic variant, a PCD genetic panel was completed; (3) if the panel was negative, whole exome sequencing (WES) was completed.

RESULTS

Since the implementation of the protocol, diagnosis was confirmed by genetic testing in 21 patients. The majority of them were of Bedouin origin (81%) and had a positive history of consanguinity (65%). Nine patients (43%) had a sibling with a confirmed diagnosis. Most patients (15/21, 71%) were diagnosed by direct pathogenic variant testing and the remainder by genetic panel (19%) and WES (10%). Disease-causing variants were found in nine genes, with DNAL1 (24%) and DNAAF3, DNAAF5, ZMYND10 (14% each) as the most prevalent ones.

CONCLUSIONS

In highly consanguineous regions, a stepwise genetic testing approach is recommended. This approach may be particularly useful in areas where the ability to obtain confirmatory diagnostic tests through other modalities is less accessible.

Late surfactant administration after 48 hours of age in preterm neonates with respiratory insufficiency: a systematic review and meta-analysis

OBJECTIVE

To systematically review and meta-analyse the effect of late surfactant administration versus placebo in reducing the incidence of death or bronchopulmonary dysplasia (BPD) in preterm infants.

DESIGN

PubMed, EMBASE, CINAHL and Cochrane CENTRAL were searched until 30 May 2023, for randomised controlled trials (RCTs) comparing administration of surfactant after 48 hours of age versus placebo in preterm ventilator-dependent neonates. The primary outcome was incidence of death or BPD at 36 weeks' postmenstrual age (PMA). Secondary outcomes included incidence of BPD at 36 weeks PMA, pre-discharge mortality, use of postnatal steroids, post-discharge respiratory support, treatment with steroids or hospitalisation prior to 1-year corrected age.

RESULTS

Pooled analyses of four RCTs (N=850) showed no statistically significant difference between groups in the incidence of death or BPD at 36 weeks' PMA (relative risk (RR) 0.99; 95% CI 0.90 to 1.10; Grades of Recommendation, Assessment, Development and Evaluation (GRADE): moderate). Late surfactant administration significantly decreased the need for post-discharge respiratory support prior to 1-year corrected age (two RCTs; N=522; RR 0.72; 95% CI 0.59 to 0.89; GRADE: low). Other secondary outcomes did not differ significantly between the groups.

CONCLUSIONS

Administration of late surfactant does not improve the rates of death or BPD at 36 weeks when administered to preterm infants with prolonged respiratory insufficiency. Additional adequately powered trials are needed to establish the efficacy of late surfactant therapy in preterm infants.

PROSPERO REGISTRATION NUMBER

CRD42023432463.

Bronchopulmonary dysplasia: temporal trend from 2010 to 2019 in the Brazilian Network on Neonatal Research

OBJECTIVE

To evaluate the temporal trend of bronchopulmonary dysplasia (BPD) in preterm infants who survived to at least 36 weeks' post-menstrual age (PMA) and BPD or death at 36 weeks' PMA, and to analyse variables associated with both outcomes.

DESIGN

Retrospective cohort with data retrieved from an ongoing national registry.

SETTING

19 Brazilian university public hospitals.

PATIENTS

Infants born between 2010 and 2019 with 23-31 weeks and birth weight 400-1499 g.

MAIN OUTCOME MEASURES

Temporal trend was evaluated by Prais-Winsten model and variables associated with BPD in survivors or BPD or death were analysed by logistic regression.

RESULTS

Of the 11 128 included infants, BPD in survivors occurred in 22%, being constant over time (annual per cent change (APC): -0.80%; 95% CI: -2.59%; 1.03%) and BPD or death in 45%, decreasing over time (APC: -1.05%; 95% CI: -1.67%; -0.43%). Being male, small for gestational age, presenting with respiratory distress syndrome, air leaks, needing longer duration of mechanical ventilation, presenting with treated patent ductus arteriosus and late-onset sepsis were associated with an increase in the chance of BPD. For the outcome BPD or death, maternal bleeding, multiple gestation, 5-minute Apgar <7, late-onset sepsis, necrotising enterocolitis and intraventricular haemorrhage were added to the variables reported above as increasing the chance of the outcome.

CONCLUSION

The frequency of BPD in survivors was constant and BPD or death decreased by 1.05% at each study year. These results show some improvement in perinatal care in Brazilian units which resulted in a reduction of BPD or death, but further improvements are still needed to reduce BPD in survivors.

Respiratory outcomes and survival after unplanned extubation in the NICU: a prospective cohort study from the SEPREVEN trial

OBJECTIVE

To compare reintubation rates after planned extubation and unplanned extubation (UE) in patients in neonatal intensive care units (NICUs), to analyse risk factors for reintubation after UE and to compare outcomes in patients with and without UE.

DESIGN

Prospective, observational study nested in a randomised controlled trial (SEPREVEN/Study on Epidemiology and PRevention of adverse EVEnts in Neonates). Outcomes were expected to be independent of the intervention tested.

SETTING

12 NICUs in France with a 20-month follow-up, starting November 2015.

PATIENTS

n=2280 patients with a NICU stay >2 days, postmenstrual age ≤42 weeks on admission.

INTERVENTIONS/EXPOSURE

Characteristics of UE (context, timing, sedative administration in the preceding 6 hours, weaning from ventilation at time of UE) and patients.

MAIN OUTCOME MEASURES

Healthcare professional-reported UE rates, reintubation/timing after extubation, duration of mechanical ventilation, mortality and bronchopulmonary dysplasia (BPD).

RESULTS

There were 162 episodes of UE (139 patients, median gestational age (IQR) 27.3 (25.6-31.7) weeks). Cumulative reintubation rates within 24 hours and 7 days of UE were, respectively, 50.0% and 57.5%, compared with 5.5% and 12.3% after a planned extubation. Independent risk factors for reintubation within 7 days included absence of weaning at the time of UE (HR, 95% CI) and sedatives in the preceding 6 hours (HR 1.93, 95% CI 1.04 to 3.60). Mortality at discharge did not differ between patients with planned extubation or UE. UE was associated with a higher risk of BPD.

CONCLUSION

In the SEPREVEN trial, reintubation followed UE in 58% of the cases, compared with 12% after planned extubation.

TRIAL REGISTRATION NUMBER

NCT02598609.

Air pollution and childhood respiratory consultations in primary care: a systematic review

BACKGROUND

Outdoor air pollution is a known risk factor for respiratory morbidity worldwide. Compared with the adult population, there are fewer studies that analyse the association between short-term exposure to air pollution and respiratory morbidity in children in primary care.

OBJECTIVE

To evaluate whether children in a primary care setting exposed to outdoor air pollutants during short-term intervals are at increased risk of respiratory diagnoses.

METHODS

A search in Medline, the Cochrane Library, Web of Science and Embase databases throughout March 2023. Percentage change or risk ratios with corresponding 95% CI for the association between air pollutants and respiratory diseases were retrieved from individual studies. Risk of bias assessment was conducted with the Newcastle-Ottawa Scale (NOS) for cohort or case-control studies and an adjusted NOS for time series studies.

RESULTS

From 1366 studies, 14 were identified as meeting the inclusion criteria. Most studies had intermediate or high quality. A meta-analysis was not conducted due to heterogeneity in exposure and health outcome. Overall, studies on short-term exposure to air pollutants (carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2) and particulate matter ≤10 µm (PM10)) were associated with increased childhood respiratory consultations in primary care. In general, exposure to ozone was associated with a reduction in respiratory consultations.

CONCLUSIONS

The evidence suggests CO, SO2, NO2, PM10 and PM2.5 are risk factors for respiratory diseases in children in primary care in the short term. However, given the heterogeneity of the studies, interpretation of these findings must be done with caution.

PROSPERO REGISTRATION NUMBER

CRD42022259279.

What is cystic fibrosis screen positive inconclusive diagnosis? And what is it not?

Since screening for cystic fibrosis (CF) was incorporated into the newborn screening program, the number of recognised variants in the CF transmembrane conductance regulator (CFTR) gene has significantly increased. This has led to the discovery of combinations of gene variants with an uncertain prognosis. One outcome is the designation of 'cystic fibrosis screen positive inconclusive diagnosis' (CFSPID). While the majority of these children are expected to be unaffected by their CFTR variants, a small proportion have been seen to develop symptoms or increasing sweat chloride levels over time, which may reflect dysfunction of the CFTR protein.As the number of children with CFSPID increases, paediatricians and those working in primary care are more likely to encounter them in their practice. It is important that professionals have an understanding of CFSPID: what it is and, importantly, what it is not (ie, they do not have CF). In this article, we hope to explore this using some example cases, illustrating the ways in which these children may present symptomatically and how to manage them.

Prolonged use of closed-loop inspired oxygen support in preterm infants: a randomised controlled trial

OBJECTIVE

This randomised study in preterm infants on non-invasive respiratory support investigated the effectiveness of automated oxygen control (A-FiO2) in keeping the oxygen saturation (SpO2) within a target range (TR) during a 28-day period compared with manual titration (M-FiO2).

DESIGN

A single-centre randomised control trial.

SETTING

A level III neonatal intensive care unit.

PATIENTS

Preterm infants (<28 weeks' gestation) on non-invasive respiratory support.

INTERVENTIONS

A-FiO2 versus M-FiO2 control.

METHODS

Main outcomes were the proportion of time spent and median area of episodes in the TR, hyperoxaemia, hypoxaemia and the trend over 28 days using a linear random intercept model.

RESULTS

23 preterm infants (median gestation 25.7 weeks; birth weight 820 g) were randomised. Compared with M-FiO2, the time spent within TR was higher in the A-FiO2 group (68.7% vs 48.0%, p<0.001). Infants in the A-FiO2 group spent less time in hyperoxaemia (13.8% vs 37.7%, p<0.001), but no difference was found in hypoxaemia. The time-based analyses showed that the A-FiO2 efficacy may differ over time, especially for hypoxaemia. Compared with the M-FiO2 group, the A-FiO2 group had a larger intercept but with an inversed slope for the daily median area below the TR (intercept 70.1 vs 36.3; estimate/day -0.70 vs 0.69, p<0.001).

CONCLUSION

A-FiO2 control was superior to manual control in keeping preterm infants on non-invasive respiratory support in a prespecified TR over a period of 28 days. This improvement may come at the expense of increased time below the TR in the first days after initiating A-FiO2 control.

TRIAL REGISTRATION NUMBER

NTR6731.

Identifying effect modifiers of systemic hydrocortisone treatment initiated 7-14 days after birth in ventilated very preterm infants on long-term outcome: secondary analysis of a randomised controlled trial

OBJECTIVE

To explore clinical effect modifiers of systemic hydrocortisone in ventilated very preterm infants for survival and neurodevelopmental outcome at 2 years' corrected age (CA).

DESIGN

Secondary analysis of a randomised placebo-controlled trial.

SETTING

Dutch and Belgian neonatal intensive care units.

PATIENTS

Infants born <30 weeks' gestational age (GA), ventilator-dependent in the second week of postnatal life.

INTERVENTION

Infants were randomly assigned to systemic hydrocortisone (cumulative dose 72.5 mg/kg; n=182) or placebo (n=190).

MAIN OUTCOME MEASURES

The composite of death or neurodevelopmental impairment (NDI) at 2 years' CA and its components. Candidate effect modifiers (GA, small for GA, respiratory index, sex, multiple births, risk of moderate/severe bronchopulmonary dysplasia or death) were analysed using regression models with interaction terms and subpopulation treatment effect pattern plots.

RESULTS

The composite outcome was available in 356 (96.0%) of 371 patients (one consent withdrawn). For this outcome, treatment effect heterogeneity was seen across GA subgroups (<27 weeks: hydrocortisone (n=141) vs placebo (n=156), 54.6% vs 66.2%; OR 0.61 (95% CI 0.38 to 0.98); ≥27 weeks: hydrocortisone (n=30) vs placebo (n=31), 66.7% vs 45.2%; OR 2.43 (95% CI 0.86 to 6.85); p=0.02 for interaction). This effect was also found for the component death (<27 weeks: 20.1% vs 32.1%; OR 0.53 (95% CI 0.32 to 0.90); ≥27 weeks: 28.1% vs 16.1%; OR 2.04 (95% CI 0.60 to 6.95); p=0.049 for interaction) but not for the component NDI. No differential treatment effects were observed across other subgroups.

CONCLUSION

This secondary analysis suggests that in infants <27 weeks' GA, systemic hydrocortisone may improve the outcome death or NDI, mainly driven by its component death. There was insufficient evidence for other selected candidate effect modifiers.

Pulmonary function outcomes after tuberculosis treatment in children: a systematic review and meta-analysis

BACKGROUND

Despite tuberculosis (TB) being a curable disease, current guidelines fail to account for the long-term outcomes of post-tuberculosis lung disease-a cause of global morbidity despite successful completion of effective treatment. Our systematic review aimed to synthesise the available evidence on the lung function outcomes of childhood pulmonary tuberculosis (PTB).

METHODS

PubMed, ISI Web of Science, Cochrane Library and ProQuest databases were searched for English-only studies without time restriction (latest search date 22 March 2023). Inclusion criteria were (1) patients who had TB with pulmonary involvement at age ≤18 years; (2) pulmonary function tests (PFTs) performed on patients after treatment completion; and (3) observational studies, including cohort and cross-sectional studies. We adhered to the recommendations of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

RESULTS

From 8040 records, 5 studies were included (involving n=567 children), with spirometry measures from 4 studies included in the meta-analyses. The effect sizes of childhood TB on forced expiratory volume in the first second and forced vital capacity z-scores were estimated to be -1.53 (95% CI -2.65, -0.41; p=0.007) and -1.93 (95% CI -3.35, -0.50; p=0.008), respectively.

DISCUSSION

The small number of included studies reflects this under-researched area, relative to the global burden of TB. Nevertheless, as childhood PTB impacts future lung function, PFTs (such as spirometry) should be considered a routine test when evaluating the long-term lung health of children beyond their completion of TB treatment. PROSPERO registration number CRD42021250172.

Xylitol for the prevention of acute otitis media episodes in children aged 1-5 years: a randomised controlled trial

OBJECTIVE

To investigate the regular use of xylitol, compared with sorbitol, to prevent acute otitis media (AOM), upper respiratory tract infections (URTIs) and dental caries.

DESIGN

Blinded randomised controlled trial with a 6-month study period.

SETTING

Enrolment took place at 11 primary care practices in Ontario, Canada.

PATIENTS

Children aged 1-5 years who did not use xylitol or sorbitol at enrolment.

INTERVENTIONS

Children were randomly assigned to use a placebo syrup with sorbitol or xylitol syrup two times per day for 6 months.

MAIN OUTCOME MEASURES

Primary outcome was the number of clinician-diagnosed AOM episodes over 6 months. Secondary outcomes were caregiver-reported URTIs and dental caries.

RESULTS

Among the 250 randomised children, the mean (SD) age was 38±14 months and there were 124 girls (50%). There were three clinician-diagnosed AOM episodes in the 125 placebo group participants and six in the 125 xylitol group participants (OR 2.04; 95% CI 0.43, 12.92; p=0.50). There was no difference in number of caregiver-reported URTI episodes (rate ratio (RR) 0.88; 95% CI 0.70, 1.11) between the placebo (4.2 per participant over 6 months; 95% CI 3.6, 5.0) and xylitol (3.7; 95% CI 3.2, 4.4) groups. Dental caries were reported for four participants in the placebo group and two in the xylitol group (OR 0.42; 95% CI 0.04, 3.05; p=0.42). In a post-hoc analysis of URTIs during the COVID-19 pandemic, the rate among the 59 participants receiving placebo was 2.3 per participant over 6 months (95% CI 1.8, 3.0) and for the 55 receiving xylitol, 1.3 over 6 months (95% CI 0.92, 1.82; RR 0.56; 95% CI 0.36, 0.87). The most common adverse event was diarrhoea (28% with placebo; 34% with xylitol).

CONCLUSIONS

Regular use of xylitol did not prevent AOM, URTIs or dental caries in a trial with limited statistical power. A post-hoc analysis indicated that URTIs were less common with xylitol exposure during the COVID-19 pandemic, but this finding could be spurious.

TRIAL REGISTRATION NUMBER

NCT03055091.

Apnoea-triggered increase in fraction of inspired oxygen in preterm infants: a randomised cross-over study

OBJECTIVES

To investigate the impact of a pre-emptive apnoea triggered oxygen response on oxygen saturation (SpO2) targeting following central apnoea in preterm infants.

DESIGN

Interventional crossover study of a 12-hour period of automated oxygen control with an apnoea response (AR) module, nested within a crossover study of a 24-hour period of automated oxygen control compared with aggregated data from two flanking 12-hour periods of manual control.

SETTING

Neonatal intensive care unit PATIENTS: Preterm infants receiving non-invasive respiratory support and supplemental oxygen; median (IQR) birth gestation 27 (26-28) weeks, postnatal age 17 (12-23) days.

INTERVENTION

Automated oxygen titration with an automated control algorithm modified to include an AR module. Alterations to inspired oxygen concentration (FiO2) were actuated by a motorised blender. Desired SpO2 range was 90-94%. Apnoea detection was by capsule pneumography.

MAIN OUTCOME MEASURES

Duration, magnitude and area under the curve (AUC) of SpO2 deviations following apnoea; frequency and duration of apnoeic events. Comparisons between periods of manual, automated and automated control with AR module.

RESULTS

In 60 studies in 35 infants, inclusion of the AR module significantly reduced AUC for SpO2 deviations below baseline compared with both automated and manual control (manual: 87.1%±107.6% s, automated: 84.6%±102.8% s, AR module: 79.4%±102.7% s). However, there was a coincident increase in SpO2 overshoot (AUC (SpO2>SpO2(onset)); manual: 44.3±99.9% s, automated: 54.7%±103.4% s, AR module: 65.7%±126.2% s).

CONCLUSION

Automated control with a pre-emptive apnoea-triggered FiO2 boost resulted in a modest reduction in post-apnoea hypoxaemia, but was followed by a greater SpO2 overshoot.

TRIAL REGISTRATION NUMBER

ACTRN12616000300471.

Ultrasound assessment of endotracheal tube depth in neonates: a prospective feasibility study

OBJECTIVE

To examine the reliability of a novel ultrasound (US) method for assessment of endotracheal tube (ETT) position in neonates.

DESIGN

Prospective, observational, single-centre, feasibility study.

SETTING

Level III neonatal intensive care unit.

PATIENTS

Term and preterm neonates requiring endotracheal intubation.

INTERVENTION

US measurement of the ETT tip to right pulmonary artery (RPA) distance was used to determine ETT position according to one-fourth to three-fourths estimated tracheal length for weight. US demonstration of pleural sliding and diaphragmatic movement was also assessed. Chest radiography (CXR) was performed following each intubation.

MAIN OUTCOME MEASURES

Agreement between US assessment of ETT tip position and CXR served as the gold standard. Sensitivity, specificity, positive and negative predictive values for each US method and correlation between ETT tip to RPA distance on US, and ETT tip to carina distance on CXR were assessed.

RESULTS

Forty-two US studies were performed on 33 intubated neonates. US evaluation of ETT-RPA distance identified 100% of ETTs positioned correctly: 77% deep and 80% high, demonstrating strong agreement with CXR (kappa=0.822). Sensitivity was 78%, specificity 100%, positive predictive value 100% and negative predictive value 86%. US ETT-RPA distance strongly correlated with CXR ETT-carina distance (r=0.826). No significant agreement was found between CXR and US assessment of pleural sliding and diaphragmatic movement. No adverse events were encountered during US scans.

CONCLUSION

US evaluation of ETT-RPA distance demonstrated excellent accuracy for determining ETT position in neonates compared with CXR. More research is needed to support its feasibility in clinical settings.

Use of pulse oximetry as an investigative test for paediatric respiratory sleep disorders

The article covers the following elements: practical and technological considerations for optimising data collection and output; reference ranges for oximetry parameters across the ages; things to consider when interpreting a pulse oximetry study (eg, sleep/wake times); the ability of pulse oximetry to predict obstructive sleep apnoea; using oximetry as a screening tool for sleep disordered breathing in children with Down syndrome; things to consider when setting up a home oximetry service; and a case of an infant being weaned from oxygen using pulse oximetry studies.

Near-fatal and fatal asthma and air pollution: are we missing an opportunity to ask key questions?

There is an increasing body of evidence supporting the link between asthma attacks and air pollution in children. To our knowledge, there has only been one reported case of a fatal asthma attack in a child associated with air pollution and this was in the UK. This article considers why there is a lack of evidence on fatal/near-fatal asthma and air pollution. We also explore three challenges. First, fatal and near-fatal asthma events are rare and not yet well understood. Second, measuring and interpreting personal exposure to air pollution with sufficient temporal and spatial detail are challenging to interpret in the context of individual fatal or near-fatal asthma attacks. Third, current studies are not designed to answer the question of whether or to what extent air pollution is associated with fatal/near-fatal asthma attacks in children. Conclusive evidence is not yet available and systems of data collection for both air pollution and fatal and near-fatal asthma attacks should be enhanced to ensure risk can be determined and impact minimised.

Haemoptysis: is it really from the lungs? The well child who spits out blood

Blood appearing in a previously well child's mouth may have many sources, and it should not be assumed to be haemoptysis, that is, coming from the respiratory tract below the larynx. In addition to the lungs and lower airways, consider also the upper airways, the mouth, gastrointestinal tract and cardiovascular conditions. This article discusses the differential diagnosis and appropriate investigations.

Ultra-high frequency lung ultrasound in preterm neonates: a test validation study on interpretation agreement and reliability

OBJECTIVE

To verify if increasing frequency, through the use of ultra-high frequency transducers, has an impact on lung ultrasound pattern recognition.

DESIGN

Test validation study.

SETTING

Tertiary academic referral neonatal intensive care unit.

PATIENTS

Neonates admitted with respiratory distress signs.

INTERVENTIONS

Lung ultrasound performed with four micro-linear probes (10, 15, 20 and 22 MHz), in random order. Anonymised images (600 dpi) were randomly included in a pictorial database: physicians with different lung ultrasound experience (beginners (n=7), competents (n=6), experts (n=5)) blindly assessed it. Conformity and reliability of interpretation were analysed using intraclass correlation coefficient (ICC), area under the curve (AUC) of the multi-class ROC analysis, correlation and multivariate linear regressions (adjusting for frequency, expertise and their interaction).

OUTCOME MEASURES

A (0-3) score based on classical lung ultrasound semiology was given to each image as done in the clinical routine.

RESULTS

ICC (0.902 (95% CI: 0.862 to 0.936), p<0.001) and AUC (0.948, p<0.001) on the whole pictorial database (48 images acquired on 12 neonates), and irrespective of the frequency and physicians' expertise, were excellent. Physicians detected more B-lines with increasing frequency: there was a positive correlation between score and frequency (ρ=0.117, p=0.001); multivariate analysis confirmed the score to be higher using 22 MHz-probes (β=0.36 (0.02-0.7), p=0.041).

CONCLUSION

Overall conformity and reliability of interpretations of lung ultrasound patterns were excellent. There were differences in the identification of the B-patterns and severe B-patterns as increasing probe frequency is associated with higher score given to these patterns.

Discharge criteria for inpatient paediatric asthma: a narrative systematic review

INTRODUCTION

Criteria-led discharges (CLDs) and inpatient care pathways (ICPs) aim to standardise care and improve efficiency by allowing patients to be discharged on fulfilment of discharge criteria. This narrative systematic review aims to summarise the evidence for use of CLDs and discharge criteria in ICPs for paediatric inpatients with asthma, and summarise the evidence for each discharge criterion used.

METHODS

Database search using keywords was performed using Medline, Embase and PubMed for studies published until 9 June 2022. Inclusion criteria included: paediatric patients <18 years old, admitted to hospital with asthma or wheeze and use of CLD, nurse-led discharge or ICP. Reviewers screened studies, extracted data and assessed study quality using the Quality Assessment with Diverse Studies tool. Results were tabulated. Meta-analysis was not performed due to heterogeneity of study designs and outcomes.

RESULTS

Database search identified 2478 studies. 17 studies met the inclusion criteria. Common discharge criteria include bronchodilator frequency, oxygen saturation and respiratory assessment. Discharge criteria definitions varied between studies. Most definitions were associated with improvements in length of stay (LOS) without increasing re-presentation or readmission.

CONCLUSION

CLDs and ICPs in the care of paediatric inpatients with asthma are associated with improvements in LOS without increasing re-presentations or readmissions. Discharge criteria lack consensus and evidence base. Common criteria include bronchodilator frequency, oxygen saturations and respiratory assessment. This study was limited by a paucity of high-quality studies and exclusion of studies not published in English. Further research is necessary to identify optimal definitions for each discharge criterion.

Neonatal high-frequency oscillatory ventilation: where are we now?

High-frequency oscillatory ventilation (HFOV) is an established mode of respiratory support in the neonatal intensive care unit. Large clinical trial data is based on first intention use in preterm infants with acute respiratory distress syndrome. Clinical practice has evolved from this narrow population. HFOV is most often reserved for term and preterm infants with severe, and often complex, respiratory failure not responding to conventional modalities of respiratory support. Thus, optimal, and safe, application of HFOV requires the clinician to adapt mean airway pressure, frequency, inspiratory:expiratory ratio and tidal volume to individual patient needs based on pathophysiology, lung volume state and infant size. This narrative review summarises the status of HFOV in neonatal intensive care units today, the lessons that can be learnt from the past, how to apply HFOV in different neonatal populations and conditions and highlights potential new advances. Specifically, we provide guidance on how to apply an open lung approach to mean airway pressure, selecting the correct frequency and use of volume-targeted HFOV.

Epidemiology of Robin sequence in the UK and Ireland: an active surveillance study

BACKGROUND

Birth prevalence of Robin sequence (RS) is commonly reported as 1 case per 8000-14 000 live births. These estimates are based on single-source case ascertainment and may miss infants who did not require hospital admission or those without overt upper airway obstruction at birth.

OBJECTIVES

To identify the true birth prevalence of RS with cleft palate in the UK and Ireland from a population-based birth cohort with high case ascertainment.

METHODS

Active surveillance of RS with cleft palate was carried out in the UK/Ireland using dual sources of case ascertainment: British Paediatric Surveillance Unit (BPSU) reporting card and nationally commissioned cleft services. Clinical data were collected from notifying clinicians at two time points.

RESULTS

173 live-born infants met the surveillance case definition, giving a birth prevalence of 1 case per 5250 live births (19.1 per 100 000 (95% CI 16.2 to 21.9)), and 1:2690 in Scotland. 47% had non-isolated RS, with Stickler syndrome the most common genetic diagnosis (12% RS cases). Birth prevalence derived from the combined data sources was significantly higher than from BPSU surveillance alone.

CONCLUSIONS

Birth prevalence of RS in the UK/Ireland derived from active surveillance is higher than reported by epidemiological studies from several other countries, and from UK-based anomaly registries, but consistent with published retrospective data from Scotland. Dual case ascertainment sources enabled identification of cases with mild or late-onset airway obstruction that were managed without hospital admission. Studies of aetiology and equivalent well-designed epidemiological studies from other populations are needed to investigate the identified geographical variability in birth prevalence.

Effectiveness of asthma preventer dispensing for preventing childhood asthma readmissions: a multisite cohort linkage study

OBJECTIVES

To (1) describe the dispensing of asthma preventers at hospital discharge and estimate its effect on hospital readmissions, and (2) estimate the effect of community asthma preventer dispensing on readmissions for the subgroup of children who were not prescribed an asthma preventer at discharge.

DESIGN

Multisite cohort study with linked administrative data.

PARTICIPANTS

Children aged 3-18 years admitted with asthma to a tertiary paediatric, mixed paediatric and adult, or regional hospital between 2017 and 2018.

MAIN OUTCOME MEASURE

Hospital readmission for asthma within 12 months.

RESULTS

Of the 767 participants, 201 (26.2%) were newly prescribed or requested to continue with asthma preventers. Of these, only 91 (45.3%) dispensed their discharge prescription within 3 days or had an active prescription. There was no evidence for a protective effect of discharge asthma preventer dispensing on asthma hospital readmissions within 12 months (OR 1.17, 95% CI 0.69 to 1.97, p=0.57). Of the 566 children who were not prescribed asthma preventers at discharge, 269 (47.5%) had one or more prescriptions dispensed in the community within 12 months. Participants who were in the protected period (asthma preventer dispensed) had reduced risk of an asthma hospital readmission (HR 0.61, 95% CI 0.36 to 1.02, p=0.06), including preschool children (HR 0.48, 95% CI 0.25, 0.93, p=0.03) on subgroup analysis.

CONCLUSIONS

There was a low rate for prescribing and dispensing of hospital discharge asthma preventers and no protective effect was found for its impact on readmissions. A protective effect on readmissions was found for community asthma preventer dispensing.

High-flow oxygen therapy in moderate to severe bronchiolitis: a randomised controlled trial

BACKGROUND AND OBJECTIVE

High-flow (HF) oxygen therapy is being used increasingly in infants with bronchiolitis, despite lack of convincing evidence of its superiority over low flow (LF). We aimed to compare the effect of HF to LF in moderate to severe bronchiolitis.

METHODS

Multicentre randomised controlled trial during four winter seasons (2016-2020) including 107 children under 2 years of age admitted with moderate to severe bronchiolitis, oxygen saturation of <92% and severely impaired vital signs. Crossovers were not allowed. HF was administered at flow rates of 2 L/kg for the first 10 kg, plus 0.5 L/kg for every kg >10 kg, LF with a maximum flow rate of 3 L/min. Primary outcome was improvement of vital signs and dyspnoea severity within 24 hours assessed by a composite score. Secondary outcomes were comfort, duration of oxygen therapy, supplemental feedings, hospitalisation duration and intensive care admission for invasive ventilation.

RESULTS

Significant improvement within 24 hours occurred in 73% of 55 patients randomised to HF and in 78% of 52 patients with LF (difference 6%, 95% CI -13% to 23%). Intention-to-treat analysis revealed no significant differences in any secondary outcome: duration of oxygen therapy, supplemental feedings, hospitalisation and need for invasive ventilation or intensive care admission, except for comfort (face, legs, activity, cry, consolability), which was one point (out of a scale of 0-10) higher in the LF group. No adverse effects occurred.

CONCLUSION

We found no measurable clinically relevant benefit in the use of HF compared with LF in hypoxic children with moderate to severe bronchiolitis.

TRIAL REGISTRATION NUMBER

NCT02913040.

Changes in UK paediatric long-term ventilation practice over 10 years

OBJECTIVES

To provide up-to-date information on the use of long-term ventilation (LTV) in the UK paediatric population and to compare the results with data collected 10 and 20 years previously.

DESIGN

A single timepoint census completed by LTV centres in the UK, carried out via an online survey.

SETTING AND PATIENTS

All patients attending paediatric LTV services in the UK.

RESULTS

Data were collected from 25 LTV centres in the UK. The total study population was 2383 children and young people, representing a 2.5-fold increase in the last 10 years. The median age was 9 years (range 0-20 years). Notable changes since 2008 were an increase in the proportion of children with central hypoventilation syndrome using mask ventilation, an increase in overall numbers of children with spinal muscular atrophy (SMA) type 1, chronic lung disease of prematurity and cerebral palsy being ventilated, and a 4.2-fold increase in children using LTV for airway obstruction. The use of 24-hour ventilation, negative pressure ventilation and tracheostomy as an interface had declined. 115 children had received a disease-modifying drug. The use of ataluren and Myozyme did not influence the decision to treat with LTV, but in 35% of the children with SMA type 1 treated with nusinersin, the clinician stated that the use of this drug had or may have influenced their decision to initiate LTV.

CONCLUSION

The results support the need for national database for children and young people using LTV at home to inform future recommendations and assist in resource allocation planning.

Syndromes associated with Robin sequence: a national prospective cohort study

OBJECTIVES

To determine the prevalence of syndromic Robin sequence (RS) in the UK and if this group of patients had an increased need for airway and feeding management compared with a non-syndromic RS cohort.

DESIGN

A prospective national multicentre study of cases submitted to the Cleft Collective cohort studies.

SETTING

Specialist cleft services in the UK.

PATIENTS

259 participants who fulfilled the diagnosis of RS. This group was compared with 548 participants with cleft palate only (CPO).

MAIN OUTCOME MEASURES

The primary outcome measure was the presence of a syndrome in patients with RS and CPO. Secondary outcome measures included the use of airway and feeding adjuncts.

RESULTS

An associated syndrome was seen in 28% of patients with RS and 14% of patients with CPO. The most common syndrome for the RS group was Stickler syndrome (27%). Syndromic status was significantly higher among patients with RS compared with those with CPO (OR 2.36, 95% CI 1.65 to 3.39; p<0.001). Patients with syndromic RS have an increased reliance on airway adjuncts compared with the patients without syndromic RS (OR 2.02, 95% CI 1.13 to 3.64; p=0.018). There was no evidence of a difference in the use of feeding adjuncts between syndromic and non-syndromic RS groups (OR 2.43, 95% CI 0.78 to 7.58; p=0.126).

CONCLUSION

The presence of a syndrome has implications for management of patients with RS. Early identification of a syndrome may help prevent the consequences of a missed syndromic diagnosis. Routine ophthalmological and genetic screening for Stickler syndrome should be mandatory for all patients with RS.

Acceleration during neonatal transport and its impact on mechanical ventilation

OBJECTIVE

During interhospital transfer, critically ill neonates frequently require mechanical ventilation and are exposed to physical forces related to movement of the ambulance. In an observational study, we investigated acceleration during emergency transfers and if they result from changes in ambulance speed and direction or from vibration due to road conditions. We also studied how these forces impact on performance of the fabian+nCPAP evolution neonatal ventilator and on patient-ventilator interactions.

METHODS

We downloaded ventilator parameters at 125 Hz and acceleration data at 100 Hz sampling rates, respectively, during the emergency transfer of 109 infants. Study subjects included term, preterm and extremely preterm infants. We computationally analysed the magnitude, direction and frequency of ambulance acceleration. We also analysed maintenance and variability of ventilator parameters and the shape of pressure-volume loops.

RESULTS

While acceleration was <1 m/s² most of the time, most babies were occasionally exposed to accelerations>5 m/s². Vibration was responsible for most of the acceleration, rather than speed change or vehicle turning. There was no significant difference between periods of high or low vibration in ventilation parameters, their variability and how well targeted parameters were kept close to their target. Speed change or vehicle turning did not affect ventilator parameters or performance. However, during periods of intense vibration, pressure-volume ventilator loops became significantly more irregular.

CONCLUSIONS

Infants are exposed to significant acceleration and vibration during emergency transport. While these forces do not interfere with overall maintenance of ventilator parameters, they make the pressure-volume loops more irregular.

Short-term pulmonary and systemic effects of hydrocortisone initiated 7-14 days after birth in ventilated very preterm infants: a secondary analysis of a randomised controlled trial

OBJECTIVE

Observational studies in preterm infants suggest that systemic hydrocortisone improves pulmonary condition but may also lead to systemic adverse effects. We report the short-term pulmonary and systemic effects of hydrocortisone initiated in the second week.

DESIGN

Randomised placebo-controlled trial.

SETTING

Dutch and Belgian neonatal intensive care units.

PATIENTS

Infants born <30 weeks' gestation and/or birth weight <1250 g, and ventilator dependent in the second week of life.

INTERVENTION

Infants were randomly assigned to a 22-day course of systemic hydrocortisone (cumulative dose 72.5 mg/kg; n=182) or placebo (n=190).

MAIN OUTCOME MEASURES

Data on extubation, ventilator settings, glucose levels, and blood pressure were recorded daily and analysed during the first 7 days of treatment using linear mixed-effects models.

RESULTS

Infants in the hydrocortisone group (24.3%) failed extubation less often compared with placebo (38.6%, crude risk difference: -14.3% (95% CI: -23.4% to -4.8%)). The estimated difference in daily rate of change between hydrocortisone and placebo was -0.42 cmH₂O (95% CI: -0.48 to -0.36) for mean airway pressure, -0.02 (95% CI: -0.02 to -0.01) for fraction of inspired oxygen, -0.37 (95% CI: -0.44 to -0.30) for respiratory index, 0.14 mmol/L (95% CI: 0.08 to 0.21) for blood glucose levels and 0.83 mm Hg (95% CI: 0.58 to 1.09) for mean blood pressure.

CONCLUSIONS

Systemic hydrocortisone initiated between 7 and 14 days after birth in ventilated preterm infants improves pulmonary condition, thereby facilitating weaning and extubation from invasive ventilation. The effects of hydrocortisone on blood glucose levels and blood pressure were mild and of limited clinical relevance.

TRIAL REGISTRATION NUMBER

Netherlands Trial Register (NTR2768; https://www.trialregister.nl/trial/2640) and European Union Clinical Trials Register (EudraCT, 2010-023777-19).

Lung ultrasound of the dependent lung detects real-time changes in lung volume in the preterm lamb

BACKGROUND

Effective lung protective ventilation requires reliable, real-time estimation of lung volume at the bedside. Neonatal clinicians lack a readily available imaging tool for this purpose.

OBJECTIVE

To determine the ability of lung ultrasound (LUS) of the dependent region to detect real-time changes in lung volume, identify opening and closing pressures of the lung, and detect pulmonary hysteresis.

METHODS

LUS was performed on preterm lambs (n=20) during in vivo mapping of the pressure-volume relationship of the respiratory system using the super-syringe method. Electrical impedance tomography was used to derive regional lung volumes. Images were blindly graded using an expanded scoring system. The scores were compared with total and regional lung volumes, and differences in LUS scores between pressure increments were calculated.

RESULTS

Changes in LUS scores correlated moderately with changes in total lung volume (r=0.56, 95% CI 0.47-0.64, p<0.0001) and fairly with right whole (r=0.41, CI 0.30-0.51, p<0.0001), ventral (r=0.39, CI 0.28-0.49, p<0.0001), central (r=0.41, CI 0.31-0.52, p<0.0001) and dorsal (r=0.38, CI 0.27-0.49, p<0.0001) regional lung volumes. The pressure-volume relationship of the lung exhibited hysteresis in all lambs. LUS was able to detect hysteresis in 17 (85%) lambs. The greatest changes in LUS scores occurred at the opening and closing pressures.

CONCLUSION

LUS was able to detect large changes in total and regional lung volume in real time and correctly identified opening and closing pressures but lacked the precision to detect small changes in lung volume. Further work is needed to improve precision prior to translation to clinical practice.

Use of xylometazoline in hospitalised infants: is it safe? A retrospective cohort study

OBJECTIVE

When infants suffer from nasal congestion, xylometazoline spray or drops can be effective to facilitate breathing and drinking. However, case reports on side effects have resulted in international warnings regarding use of xylometazoline in infants. Nevertheless, the incidence of these side effects in hospitalised infants is unknown.

DESIGN

Retrospective cohort study.

SETTING

Teaching hospital between 2017 and 2021.

PATIENTS

Infants under 2 years of age.

EXPOSURE

Receiving either saline-only (unlimited frequency, concentration 0.9%) or in combination with xylometazoline (maximum three times daily, concentration 0.025%).

MAIN OUTCOME MEASURES

Predefined potential side effects (events), including among others apnoea, nausea, bradycardia, cyanosis and nosebleeds, were extracted from patient records, and the probability to be caused by saline only or xylometazoline-saline was determined using the ADR Probability Scale.

RESULTS

We included 898 admitted children during 1285 treatment episodes who received saline with or without xylometazoline. 26 events occurred in the saline-only group (incidence 20.0/100 treatment episodes), and 117 events occurred in the xylometazoline saline group (incidence of 10.5/100 treatment episodes), which was significantly lower (OR 0.47 95% CI 0.29 to 0.75, p=0.002). No definite linked or life-threatening events were found. Three nosebleeds had a probable link to the use of xylometazoline-saline, and all other events could only possibly be linked to saline-only or xylometazoline saline use. The incidence of all events was higher in the saline-only group as compared with the xylometazoline saline group, except nausea, which had a similar occurrence (p=0.65). Results were very similar across (gestational) age groups, gender and reasons for admission.

CONCLUSION

The use of low-dose xylometazoline seems to be safe in hospitalised infants.

Thresholds for surfactant use in preterm neonates: a network meta-analysis

OBJECTIVE

To perform a network meta-analysis of randomised controlled trials of different surfactant treatment strategies for respiratory distress syndrome (RDS) to assess if a certain fraction of inspired oxygen (FiO₂) is optimal for selective surfactant therapy.

DESIGN

Systematic review and network meta-analysis using Bayesian analysis of randomised trials of prophylactic versus selective surfactant for RDS.

SETTING

Cochrane Central Register of Controlled Trials, MEDLINE, Embase and Science Citation Index Expanded.

PATIENTS

Randomised trials including infants under 32 weeks of gestational age.

INTERVENTIONS

Intratracheal surfactant, irrespective of type or dose.

MAIN OUTCOME MEASURES

Our primary outcome was neonatal mortality, compared between groups treated with selective surfactant therapy at different thresholds of FiO₂. Secondary outcomes included respiratory morbidity and major complications of prematurity.

RESULTS

Of 4643 identified references, 14 studies involving 5298 participants were included. We found no statistically significant differences between 30%, 40% and 50% FiO₂ thresholds. A sensitivity analysis of infants treated in the era of high antenatal steroid use and nasal continuous positive airway pressure as initial mode of respiratory support showed no difference in mortality, RDS or intraventricular haemorrhage alone but suggested an increase in the combined outcome of major morbidities in the 60% threshold.

CONCLUSION

Our results do not show a clear benefit of surfactant treatment at any threshold of FiO₂. The 60% threshold was suggestive of increased morbidity. There was no advantage seen with prophylactic treatment. Randomised trials of different thresholds for surfactant delivery are urgently needed to guide clinicians and provide robust evidence.

PROSPERO REGISTRATION NUMBER

CRD42020166620.

Enhancing respiratory disease diagnosis by bronchoalveolar lavage in Kashmir: an audit of findings

OBJECTIVE

To study bronchoalveolar lavage (BAL) findings in various respiratory diseases in children in Kashmir India.

DESIGN

Prospective observational study.

SETTING

Paediatric department of the tertiary care hospital.

PATIENTS

Children of both genders from 1 month to 17 years of age INTERVENTION: All studied patients underwent flexible bronchoscopy and BAL.

OUTCOME MEASURE

To observe the BAL findings in various respiratory diseases in the studied population.

RESULTS

A total of 283 patients underwent BAL procedure. The positive BAL report was received in 131 (46%) patients. Out of these, 55 (42%) patients had positive BAL culture/ microscopy for different bacterial (50) and fungal species (Candida spp (3), Mucormycosis (1) and Aspergillus (1)). MTB was isolated in 25 (19%) patients. Twenty-three (17.5%) patients had bronchoalveolar lavage fluid (BALF) positive for pulmonary hydatidosis. Foamy macrophages were seen in 13 patients, significant eosinophilia in nine patients and hemosiderin-laden macrophages were seen in three patients.

CONCLUSION

We found BALF a very useful sample for the evaluation of many infective and non-infective respiratory diseases in our region, which otherwise lacks high end diagnostics. 46% of our patients had some abnormalities in the BAL specimen. It provided us with valuable information regarding organism profile and drug sensitivity in case of lung infection. BALF analysis was also found useful in the diagnosis of some non-infective pulmonary disorders like acute eosinophilic pneumonia, aspiration syndromes and bronchial asthma.

How to interpret spirometry in a child with suspected asthma

Asthma is one of the most common chronic disorders of childhood. The typical symptoms are a result of reversible airway obstruction. There is no 'gold-standard' test to diagnose asthma, but the most commonly used investigation to help with a diagnosis is spirometry. This article outlines some of the technical aspects of spirometry together with how the forced expiration manoeuver and bronchodilator responsiveness testing can be performed and interpreted in a child with suspected asthma.

Nasal high-flow therapy to Optimise Stability during Intubation: the NOSI pilot trial

OBJECTIVE

In adult patients with acute respiratory failure, nasal high-flow (NHF) therapy at the time of intubation can decrease the duration of hypoxia. The objective of this pilot study was to calculate duration of peripheral oxygen saturation below 75% during single and multiple intubation attempts in order to inform development of a larger definitive trial.

DESIGN AND SETTING

This double-blinded randomised controlled pilot trial was conducted at a single, tertiary neonatal centre from October 2020 to October 2021.

PARTICIPANTS

Infants undergoing oral intubation in neonatal intensive care were included. Infants with upper airway anomalies were excluded.

INTERVENTIONS

Infants were randomly assigned (1:1) to have NHF 6 L/min, FiO₂ 1.0 or NHF 0 L/min (control) applied during intubation, stratified by gestational age (<34 weeks vs ≥34 weeks).

MAIN OUTCOME MEASURES

The primary outcome was duration of hypoxaemia of <75% up to the time of successful intubation, RESULTS: 43 infants were enrolled (26 <34 weeks and 17 ≥34 weeks) with 50 intubation episodes. In infants <34 weeks' gestation, median duration of SpO₂ of <75% was 29 s (0-126 s) vs 43 s (0-132 s) (p=0.78, intervention vs control). Median duration of SpO_{2 of} <75% in babies ≥34 weeks' gestation was 0 (0-32 s) vs 0 (0-20 s) (p=0.9, intervention vs control).

CONCLUSION

This pilot study showed that it is feasible to provide NHF during intubation attempts. No significant differences were noted in duration of oxygen saturation of <75% between groups; however, this trial was not powered to detect a difference. A larger, higher-powered blinded study is warranted.

Diaphragm electrical activity during weaning of nasal high-flow therapy in preterm infants

OBJECTIVE

To determine whether electrical activity of the diaphragm (Edi) changes with weaning nasal high-flow (HF) therapy in preterm infants according to a standardised protocol.

DESIGN

Prospective observational cohort study.

SETTING

Neonatal intensive care unit.

PATIENTS

Preterm infants born at <32 weeks gestation, receiving nasal HF as part of routine clinical care.

INTERVENTIONS

Infants recruited to the study had their HF weaned according to set clinical criteria. Edi was measured using a modified gastric feeding tube serially from baseline (pre-wean) to 24-hours post-wean.

MAIN OUTCOME MEASURES

Change in Edi from baseline was measured at four time points up to 24 hours after weaning. Minimum Edi during expiration, maximum Edi during inspiration and amplitude of the Edi signal (Edi_delta) were measured. Clinical parameters (heart rate, respiratory rate and fraction of inspired oxygen) were also recorded.

RESULTS

Forty preterm infants were recruited at a mean corrected gestational age of 31.6 (±2.7) weeks. Data from 156 weaning steps were analysed, 91% of which were successful. Edi did not change significantly from baseline during flow reduction steps, but a significant increase in diaphragm activity was observed when discontinuing HF (median increase in Edi_delta immediately post-discontinuation 1.7 µV (95% CI: 0.6 to 3.0)) and at 24 hours 1.9 µV (95% CI: 0.7 to 3.8)). No significant difference in diaphragm activity was observed between successful and unsuccessful weaning steps.

CONCLUSIONS

A protocolised approach to weaning has a high probability of success. Edi does not change with reducing HF rate, but significantly increases with discontinuation of HF from 2 L/min.

Higher childhood pneumonia admission threshold remains in Lao PDR: an observational study

OBJECTIVES

WHO Integrated Management of Childhood Illness (IMCI) guidelines changed pneumonia hospitalisation criteria in 2014, which was implemented in Lao People's Democratic Republic (Lao PDR) in 2015. We determined adherence to: current (2014) IMCI guidelines for children presenting to hospitals with pneumonia, current outpatient management guidelines and identified hospitalisation predictors.

DESIGN

Prospective observational study (January 2017 to December 2018).

SETTING

Outpatient and emergency departments of four hospitals in Vientiane, Lao PDR.

PATIENTS

594 children aged 2-59 months diagnosed with pneumonia.

MAIN OUTCOME MEASURES

Number of children diagnosed, hospitalised, managed, administered preventive measures and followed-up accordant with current guidelines.

RESULTS

Non-severe and severe pneumonia were correctly diagnosed in 97% and 43% of children, respectively. Non-severe pneumonia with lower chest wall indrawing (LCI) was diagnosed as severe in 15%. Hospitalisation rates were: 80% for severe pneumonia, 86% and 3% for non-severe pneumonia with and without LCI, respectively. Outpatient oral antibiotic prescribing was high (99%), but only 30% were prescribed both the recommended antibiotic and duration. Appropriate planned follow-up was 89%. Hospitalisation predictors included age 2-5 months (compared with 24-59 months; OR 3.95, 95% CI 1.90 to 8.24), public transport to hospital (compared with private vehicle; OR 2.60, 95% CI 1.09 to 6.24) and households without piped drinking water (OR 4.67, 95% CI 2.75 to 7.95).

CONCLUSIONS

Hospitalisation practice for childhood pneumonia in Lao PDR remains more closely aligned with the 2005 WHO IMCI guidelines than the currently implemented 2014 iteration. Compliance with current outpatient antibiotic prescribing guidelines was low.