Preemptive high-flow nasal cannula treatment in severe bronchiolitis: Results from a high-volume, resource-limited pediatric emergency department

Predictive factors for high-flow nasal cannula failure in patients with acute viral bronchiolitis admitted to the pediatric intensive care unit

OBJECTIVE

To identify predictive factors for failure in the installation of high-flow nasal cannulas in children diagnosed with acute viral bronchiolitis under 24 months of age admitted to the pediatric intensive care unit.

METHODS

This work was a retrospective single-center cohort study conducted from March 2018 to July 2023 involving infants under 24 months of age who were diagnosed with acute viral bronchiolitis and who received high-flow nasal cannulas upon admission to the pediatric intensive care unit. Patients were categorized into two groups, the Success Group and Failure Group, on the basis of high-flow nasal cannula therapy efficacy. The primary outcome was treatment failure, which was defined as the transition to invasive or noninvasive ventilation. The analyzed variables included age, sex, weight, high-flow nasal cannula parameters, vital signs, risk factors, comorbidities, and imaging. Acute viral bronchiolitis severity was assessed using the Wood-Downes Scale, and functional status was assessed via the Functional Status Scale, both of which were administered by trained physiotherapists.

RESULTS

In total, 162 infants with acute viral bronchiolitis used high-flow nasal cannulas, with 17.28% experiencing treatment failure. The significant differences between the Failure and Success Groups included age (p = 0.001), weight (p = 0.002), bronchiolitis severity (p = 0.004), initial high-flow nasal cannula flow (p = 0.001), and duration of use (p = 0.000). The cutoff values for initial flow (≤ 12L/min), weight (≤ 5kg), and Wood-Downes score (≥ 9 points) were determined from the ROC curves. Initial flow ≤ 12L/min was the most predictive for failure (AUC = 0.71; 95%CI: 0.61 - 0.84; p = 0.001). Multivariate analysis indicated that weight was a protective factor (RR = 0.87; 95%CI: 0.78 - 0.98), duration of use reduced the risk of failure (RR = 0.49; 95%CI: 0.38 - 0.64; p = 0.000), and Wood-Downes score was not significant (RR = 1.04; 95%CI: 0.95 - 1.14; p = 0.427). Weight explained 84.7% of the variation in initial flow.

CONCLUSION

Risk factors for high-flow nasal cannula therapy failure in bronchiolitis patients include younger age, consequently lower weight, and a lower initial flow rate.

Epidemiologic evaluation of pediatric patients receiving high-flow nasal cannula therapy in the pediatric emergency department

High-flow nasal cannula (HFNC) therapy has emerged as an important method of respiratory support in the pediatric emergency department (ED), but its optimal use and factors affecting success require further investigation. The aim of this study was to evaluate the diagnosis and treatment response of patients receiving HFNC therapy in the pediatric ED and to investigate the factors affecting the success of HFNC therapy. This retrospective, cross-sectional study analyzed the data of 415 patients admitted to the Pediatric ED of the Istanbul Medical Faculty from 2021 to 2022 who received HFNC therapy. Treatment failure was defined as the required noninvasive ventilation (NIV) or intubation. Diagnoses were confirmed by examination findings, radiological imaging, laboratory tests and other hospital admissions. Respiratory disease was diagnosed in 88.2% of patients. The most common diagnoses were bronchiolitis (48%), pneumonia (23.6%), asthma (9.6%), reactive airway disease (5.8%), and heart failure (4.8%). Among the patients, 55.4% were admitted to the pediatric service, 28% were admitted to the intensive care unit, 8.7% were discharged, and 7.7% left the ED with a referral to an external center. HFNC therapy ended with symptom regression in 63.9% of patients, transition to NIV in 25.8%, and intubation in 4.3%. Although patients did not respond to HFNC therapy at 0 to 1 hour, a HFNC response was observed in almost half of the patients in the following periods. The presence of chronic disease and abnormal chest radiography findings were found to be independent risk factors for treatment failure, whereas the presence of allergic disease and the duration of HFNC therapy were found to be protective factors. HFNC therapy was effective in most pediatric patients with respiratory distress. Clinicians should consider extending HFNC therapy beyond the first hour in initial nonresponders, as significant improvement may occur in the following hours. Chronic disease and abnormal chest radiography findings were independent risk factors for failure of HFNC therapy. Conversely, allergic disease and longer HFNC duration were protective. Clinical and laboratory parameters should be considered when evaluating the efficacy of HFNC therapy. Therefore, patients should be evaluated individually, and treatment should be planned.

Application of the TIDieR checklist to improve the HFNC use in bronchiolitis management

The use of High-Flow Nasal Cannula (HFNC) in children with bronchiolitis is globally increased in the last decade, despite the lack of evidence-based and universal guidelines to standardize their application in the clinical practice. In this systematic review, we aimed to analyse the completeness of previous studies on HFNC interventions in children with bronchiolitis using an adapted Template for Intervention Description and Replication (TIDieR) checklist. Randomized clinical trials (RCTs) and cohort studies on children younger than 2 years old with a diagnosis of bronchiolitis were included. We analysed manuscripts published between January 2010 and October 2023. An adapted TIDieR checklist based on 14 items about HFNC interventions was used to assess the completeness of the studies. A total sample of 67,324 patients was analysed in the 78 included manuscripts (21 RCTs and 57 cohort studies). Completeness of TIDieR checklist items ranged from 1% to 100%. The most reported items were related to the study rationale and the selection strategy (inclusion/exclusion criteria), identifying high quality of patients' selection in the included manuscripts. However, most of the studies did not provide separate indications for children with comorbidities. Only 23% of studies reported a complete definition and rates of treatment failure suggesting that this item needs more clarification in future studies. A minority of articles (40%) described the HFNC weaning procedures. Interestingly, most of the interventions took place in ICUs (61%), showing how, in the last decade, this location was the most cited for the use of HFNC in children with bronchiolitis.

CONCLUSIONS

 Our results suggest complete reporting of our TIDieR checklist in future studies may improve the quality of the research on HFNC use in children with bronchiolitis. Our findings encourage researchers to clarify the personalization of treatment administration and to better define the criteria for treatment failure. The adoption of universal definitions in this field is needed to increase the results' comparability and create standardized protocols. Researchers may use the proposed TIDieR checklist to develop, conduct and report clinical research into HFNC and bronchiolitis as this may help to create a consensus for establishing an evidence-based protocol for HFNC.

WHAT IS KNOWN

• High-flow nasal cannula (HFNC) is a common device used in children with bronchiolitis in the presence of respiratory distress, after the failure of standard oxygen therapy. However, no evidence-based and standardized protocol for the use of this device is globally available.

WHAT IS NEW

• By using an adapted Template for Intervention Description and Replication (TIDieR) checklist to review previous studies on HFNC in bronchiolitis, we found a global heterogeneity in the description of interventions with some items of the checklist poorly reported. Thus, we suggest using our TIDieR checklist for developing, conducting and reporting clinical research into HFNC and bronchiolitis as this may help to create a consensus for establishing an evidence-based protocol for HFNC.

Effectiveness of high flow nasal Cannula (HFNC) therapy compared to standard oxygen therapy (SOT) and continuous positive airway pressure (CPAP) in bronchiolitis

High Flow Nasal Cannula therapy (HFNC) is a form of respiratory support for bronchiolitis. Recent evidence confirms HFNC reduces the risk of treatment escalation by nearly half (45%) compared to standard oxygen therapy (SOT), although most patients (75%) with mild-moderate respiratory distress manage well on SOT. The majority of children (60%) failing SOT respond well to HFNC making rescue use of HFNC a more cost-effective approach compared to its first-line use. HFNC is compared toCPAP in the setting of moderate to severe bronchiolitis. Patients on HFNC have a slightly elevated risk of treatment failure especially in severe bronchiolitis, but this does not translate to a significant difference in patient or healthcare centred outcomes. HFNC has improved tolerance, a lower complication rate and is more easily available in peripheral hospitals. It is therefore the preferred first line option followed by rescue CPAP. HFNC is clinically effective and safe to use in bronchiolitis of all severities.

Understanding the use and outcomes of high-flow nasal cannula among infants admitted to Canadian hospitals with bronchiolitis (CanFLO): a protocol for a multicentre, retrospective cohort study

INTRODUCTION

Bronchiolitis is the most common viral lower respiratory tract infection in children under 2 years of age. Respiratory support with high-flow nasal cannula (HFNC) is increasingly used in this patient population with limited understanding of the patients most likely to benefit and considerable practice variability of use. This study aims to understand the factors associated with failure of HFNC support among patients with bronchiolitis and to describe the current practice variations of HFNC use in patients with bronchiolitis in Canadian hospitals including fluid management and parameters to initiate, escalate and discontinue HFNC support.

METHODS AND ANALYSIS

This is a multicentre retrospective cohort study including hospitalised patients aged 0-24 months with bronchiolitis requiring support with HFNC between January 2017 and December 2021. Clinical data will be collected from patient medical records from Canadian hospitals (n=12), including academic and community centres. HFNC failure will be defined as the need for escalation to non-invasive or invasive mechanical ventilation. Factors associated with HFNC failure will be analysed using logistic regression. Descriptive statistics will be used to describe practice variations of HFNC utilisation and management.

ETHICS AND DISSEMINATION

Approval from the Research Ethics Boards (REBs) has been obtained for each participating study site prior to onset of data collection including Clinical Trials Ontario for all Ontario hospital sites and REBs from British Columbia Children's Hospital, Stollery Children's Hospital, Montreal Children's Hospital and CHU Sainte-Justine. Study results will be disseminated through presentation at national/international conferences and publication in high-impact, peer-reviewed journals.

Use of high-flow cannula in pediatric patients with respiratory failure: A prospective cohort study in three high-altitude hospitals

Background and Aims

Acute respiratory failure (ARF) is a common cause of morbimortality, and a frequent reason for admission to the pediatric intensive care unit (PICU). It requires a high-flow oxygen device as treatment. Our aim is to determine the frequency and main indications for the use of high-flow nasal cannula (HFNC), and the prevalence of HFNC failure and its main causes, in three hospitals.

Methods

It is a multicenter prospective cohort study, developed in three hospitals in Bogota. Eligible patients were children older than 1 month and younger than 18 years who presented ARF and required management with an HFNC. The study was carried out between April 2020 and December 2021. The follow-up was carried out at 1, 6, and 48 h after starting the management.

Results

Of 685 patients included in the study, 296 developed ARF. The prevalence of patients with ARF who required management with HFNC was 48%. The frequency of the pathologies that cause the ARF was: Bronchiolitis was the most frequent pathology (34.5%), followed by asthmatic crisis (15.5%) and pneumonia (12.7%). The average time of use of HFNC was 81.6 h. Regarding treatment failure with HFNC, 15 patients presented torpid evolution and required invasive mechanical ventilation, with a prevalence of therapeutic failure of the HFNC of 10.6%.

Conclusion

The use of HFNC is more frequent in patients with bronchiolitis, in children under 2 years of age and in males, which is in line with what has been reported in the literature. In addition, the failure rate of HFNC is low (10.6%), and it may be useful in other pathologies besides bronchiolitis, such as asthma, pneumonia, among others. It opens the possibility to continue evaluating the role of HFNC in pediatric pathology in new studies.

Update on the Role of High-Flow Nasal Cannula in Infants with Bronchiolitis

Bronchiolitis (BR), a lower respiratory tract infection mainly caused by respiratory syncytial virus (RSV), can be very severe. Presently, adequate nutritional support and oxygen therapy remain the only interventions recommended to treat patients with BR. For years, mild BR cases were treated with noninvasive standard oxygen therapy (SOT), i.e., with cold and poorly or totally non-humidified oxygen delivered by an ambient headbox or low-flow nasal cannula. Children with severe disease were intubated and treated with invasive mechanical ventilation (IMV). To improve SOT and overcome the disadvantages of IMV, new measures of noninvasive and more efficient oxygen administration have been studied. Bi-level positive air way pressure (BiPAP), continuous positive airway pressure (CPAP), and high-flow nasal cannula (HFNC) are among them. For its simplicity, good tolerability and safety, and the good results reported in clinical studies, HFNC has become increasingly popular and is now widely used. However, consistent guidelines for initiation and discontinuation of HFNC are lacking. In this narrative review, the role of HFNC to treat infants with BR is discussed. An analysis of the literature showed that, despite its widespread use, the role of HFNC in preventing respiratory failure in children with BR is not precisely defined. It is not established whether it can offer greater benefits compared to SOT and when and in which infants it can replace CPAP or BiPAP. The analysis of the results clearly indicates the need for multicenter studies and official guidelines. In the meantime, HFNC can be considered a safe and effective method to treat children with mild to moderate BR who do not respond to SOT.