High-flow nasal cannula oxygen therapy for infants with bronchiolitis: pilot study

Nasal high flow therapy for bronchiolitis

AIM

Uptake of nasal high-flow therapy in infants with bronchiolitis has grown in the last decade with some evidence suggesting a reduction in escalation of care. The effect of the implementation of recent available evidence on clinical practice remains unclear.

METHODS

In a prospective observational study over 6 months in six metropolitan hospitals in Australia, we investigated the clinical practice of high-flow in infants admitted with bronchiolitis and an oxygen requirement. To assess the choice by clinicians of the initial oxygen therapy (standard oxygen or high-flow) the disease severity was measured by physiological parameters obtained prior to oxygen therapy commencement. Additional secondary outcomes were hospital length of stay and transfers to intensive care.

RESULTS

Two hundred thirty-five infants with bronchiolitis were admitted for oxygen therapy over 6 months during the winter season. Infants who received high-flow on admission to hospital displayed significantly higher respiratory rates, higher heart rates and higher early warning tool scores with more severe work of breathing than those commenced on standard oxygen therapy as a first line of oxygen therapy. A significantly longer hospital length of stay of 0.6 days occurred in infants commenced on high-flow. A significantly greater proportion on high-flow (23.3%) were admitted to intensive care compared to infants commenced on SOT (10.4%) despite the severity of disease in both groups being similar.

CONCLUSIONS

Infants with bronchiolitis presenting with greater disease severity are more likely to receive high-flow therapy. Escalation of care in an intensive care unit occurred more frequently on infants on high-flow.

TRIAL REGISTRATION

This trial is registered in the Australian New Zealand Clinical Trial Registry ACTRN12618001206213.

High flow, low results: The limits of high flow nasal cannula in the treatment of bronchiolitis

Bronchiolitis continues to be the most common cause of hospitalization in the first year of life. We continue to search for the remedy that will improve symptoms, shorten hospitalization and prevent worsening of disease. Although initially thought to be a promising therapy, large randomized controlled trials show us that high flow nasal cannula (HFNC) use is not that remedy. These trials show no major differences in duration of hospital stay, intensive care unit (ICU) admission rates, duration of stay in the ICU, duration of oxygen therapy, intubation rates, heart rate, respiratory rate or comfort scores. Additionally, practices regarding initiation, flow rates and weaning continue to vary from institution to institution and there are currently no agreed upon indications for its use. This reveals the need for evidence based guidelines on HFNC use in bronchiolitis.

Cost-effectiveness of nasal high-flow in children with acute hypoxaemic respiratory failure

AIM

A pilot randomised controlled trial assessed the early application of nasal high-flow (NHF) therapy compared with standard oxygen therapy (SOT), in children aged 0 to 16 years presenting to paediatric emergency departments with acute hypoxaemic respiratory failure (AHRF). The study estimated the need to escalate therapy and hospital length of stay in the NHF group compared with SOT. This sub-study then assessed the subsequent cost-effectiveness.

METHODS

A decision tree-based model was developed, alongside the clinical study, to estimate cost-effectiveness, from the healthcare sector perspective. The primary health economics outcome is measured as incremental cost per length of hospital stay avoided. Incremental cost effectiveness ratios (ICER) measuring change in cost per change in length of stay, were obtained for four samples, depending on responder status and obstructive airways disease. These were (1) obstructive and responder, (2) non-obstructive and responder, (3) obstructive and non-responder and (4) non obstructive and non-responder. Bootstrapping of parameters accounted for uncertainty in estimates of cost and outcome.

RESULTS

The ICER for patients randomised to NHF, indicated an additional A$367.20 for a lower hospital length of stay (in days) in the non-obstructive/non-responder sample. In the bootstrap sample, this was found to be cost effective above a willingness to pay threshold of A$10 000. The ICER was A$440.86 in the obstructive/responder sample and A$469.56 in the non-obstructive/responder sample - but both resulted in a longer length of stay. The ICER in the obstructive/non-responder sample was A$52 167.76, also with a longer length of stay, mainly impacted by a small sample of severe cases.

CONCLUSION

As first-line treatment, NHF is unlikely to be cost-effective compared with SOT, but for non-obstructive patients who required escalation in care (non-obstructive non-responder), NHF is likely to be cost-effective if willingness-to-pay per reduced hospital length of stay is more than A$10 000 per patient.

When to Transfer: Predictors of Pediatric High Flow Nasal Cannula Failure at a Community Hospital

OBJECTIVES

To identify risk factors of high flow nasal cannula (HFNC) failure at a US pediatric hospital without a co-located ICU.

METHODS

Retrospective cohort study of patients aged 0 to 18 years who were started on HFNC in the emergency department or inpatient unit at a community hospital over a 16-month period. Children with chronic medical conditions were excluded. Outcome was HFNC failure, defined as HFNC need greater than floor limit, noninvasive positive pressure, or mechanical ventilation. In bivariate analysis, we compared demographic and clinical factors between those with and without failure. We included variables in a multivariable model on the basis of statistical significance. We used Poisson regression with robust error variance to calculate the adjusted relative risk (aRR) of failure for each variable.

RESULTS

Of 195 children, 51% had HFNC failure. In adjusted analysis, failure was higher in all age groups <12 months as compared with older children. For example, children aged 3 to 5 months had a higher risk of failure compared with patients 12 months or older (aRR 1.85, confidence interval [CI] 1.34-2.54). Patients with an asthma exacerbation had a higher risk of failure (aRR 1.39, CI 1.03-1.88). Patients whose respiratory rate or heart rate did not improve also had a higher risk of failure (aRR 1.73, CI 1.24-2.41; aRR 1.47, CI 1.14-1.90).

CONCLUSIONS

Patients who were younger, had asthma, and did not have improved respiratory rate or heart rate after HFNC were more likely to experience HFNC failure.

High flow nasal cannula for respiratory support in term infants

BACKGROUND

Respiratory failure or respiratory distress in infants is the most common reason for non-elective admission to hospitals and neonatal intensive care units. Non-invasive methods of respiratory support have become the preferred mode of treating respiratory problems as they avoid some of the complications associated with intubation and mechanical ventilation. High flow nasal cannula (HFNC) therapy is increasingly being used as a method of non-invasive respiratory support. However, the evidence pertaining to its use in term infants (defined as infants ≥ 37 weeks gestational age to the end of the neonatal period (up to one month postnatal age)) is limited and there is no consensus of opinion regarding the safety and efficacy HFNC in this population.

OBJECTIVES

To assess the safety and efficacy of high flow nasal cannula oxygen therapy for respiratory support in term infants when compared with other forms of non-invasive respiratory support.

SEARCH METHODS

We searched the following databases in December 2022: Cochrane CENTRAL; PubMed; Embase; CINAHL; LILACS; Web of Science; Scopus. We also searched the reference lists of retrieved studies and performed a supplementary search of Google Scholar.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that investigated the use of high flow nasal cannula oxygen therapy in infants ≥ 37 weeks gestational age up to one month postnatal age (the end of the neonatal period).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility, performed data extraction, and assessed risk of bias in the included studies. Where studies were sufficiently similar, we performed a meta-analysis using mean differences (MD) for continuous data and risk ratios (RR) for dichotomous data, with their respective 95% confidence intervals (CIs). For statistically significant RRs, we calculated the number needed to treat for an additional beneficial outcome (NNTB). We used the GRADE approach to evaluate the certainty of the evidence for clinically important outcomes.

MAIN RESULTS

We included eight studies (654 participants) in this review. Six of these studies (625 participants) contributed data to our primary analyses. Four studies contributed to our comparison of high flow nasal cannula (HFNC) oxygen therapy versus continuous positive airway pressure (CPAP) for respiratory support in term infants. The outcome of death was reported in two studies (439 infants) but there were no events in either group. HFNC may have little to no effect on treatment failure, but the evidence is very uncertain (RR 0.98, 95% CI 0.47 to 2.04; 3 trials, 452 infants; very low-certainty evidence). The outcome of chronic lung disease (need for supplemental oxygen at 28 days of life) was reported in one study (375 participants) but there were no events in either group. HFNC may have little to no effect on the duration of respiratory support (any form of non-invasive respiratory support with or without supplemental oxygen), but the evidence is very uncertain (MD 0.17 days, 95% CI -0.28 to 0.61; 4 trials, 530 infants; very low-certainty evidence). HFNC likely results in little to no difference in the length of stay at the intensive care unit (ICU) (MD 0.90 days, 95% CI -0.31 to 2.12; 3 trials, 452 infants; moderate-certainty evidence). HFNC may reduce the incidence of nasal trauma (RR 0.16, 95% CI 0.04 to 0.66; 1 trial, 78 infants; very low-certainty evidence) and abdominal overdistension (RR 0.22, 95% CI 0.07 to 0.71; 1 trial, 78 infants; very low-certainty evidence), but the evidence is very uncertain. Two studies contributed to our analysis of HFNC versus low flow nasal cannula oxygen therapy (LFNC) (supplemental oxygen up to a maximum flow rate of 2 L/min). The outcome of death was reported in both studies (95 infants) but there were no events in either group. The evidence suggests that HFNC may reduce treatment failure slightly (RR 0.44, 95% CI 0.21 to 0.92; 2 trials, 95 infants; low-certainty evidence). Neither study reported results for the outcome of chronic lung disease (need for supplemental oxygen at 28 days of life). HFNC may have little to no effect on the duration of respiratory support (MD -0.07 days, 95% CI -0.83 to 0.69; 1 trial, 74 infants; very low-certainty evidence), length of stay at the ICU (MD 0.49 days, 95% CI -0.83 to 1.81; 1 trial, 74 infants; very low-certainty evidence), or hospital length of stay (MD -0.60 days, 95% CI -2.07 to 0.86; 2 trials, 95 infants; very low-certainty evidence), but the evidence is very uncertain. Adverse events was an outcome reported in both studies (95 infants) but there were no events in either group. The risk of bias across outcomes was generally low, although there were some concerns of bias. The certainty of evidence across outcomes ranged from moderate to very low, downgraded due to risk of bias, imprecision, indirectness, and inconsistency.

AUTHORS' CONCLUSIONS

When compared with CPAP, HFNC may result in little to no difference in treatment failure. HFNC may have little to no effect on the duration of respiratory support, but the evidence is very uncertain. HFNC likely results in little to no difference in the length of stay at the intensive care unit. HFNC may reduce the incidence of nasal trauma and abdominal overdistension, but the evidence is very uncertain. When compared with LFNC, HFNC may reduce treatment failure slightly. HFNC may have little to no effect on the duration of respiratory support, length of stay at the ICU, or hospital length of stay, but the evidence is very uncertain. There is insufficient evidence to enable the formulation of evidence-based guidelines on the use of HFNC for respiratory support in term infants. Larger, methodologically robust trials are required to further evaluate the possible health benefits or harms of HFNC in this patient population.

Randomized Trial of Weight-Based Versus Fixed Limit High-Flow Nasal Cannula in Bronchiolitis

BACKGROUND

High flow nasal cannula (HFNC) is increasingly used to treat bronchiolitis. Although lower HFNC rates (≤8 L per minute) are commonly employed, higher weight-based flows more effectively alleviate dyspnea. The impact of higher flows on the need for care escalation is unclear.

METHODS

A randomized clinical trial was performed in a community hospital inpatient pediatric unit. Patients with bronchiolitis on HFNC were randomized to an existing "standard" HFNC protocol (max flow of 8 L per minute), or to a novel weight-based protocol (max flow of 2 L/kg per minute). Weaning of HFNC for the patients in the standard arm was left to provider discretion but was prescribed in the weight-based arm. The primary outcome was interhospital transfer to a PICU. The study was powered to detect a 35% difference in transfer rate.

RESULTS

51 patients were randomized to the weight-based or standard HFNC arms. The interhospital PICU transfer rate did not differ significantly between the standard (41.7%) and weight-based arms (51.9%) P = .47. Hospital length of stay was significantly shorter in the weight-based arm with protocolized weaning (45 h [interquartile range 42.1-63.3] versus 77.6 h [interquartile range 47.3-113.4]); P = .01. There were no significant adverse events in either group.

CONCLUSIONS

Weight-based provision of HFNC did not significantly impact the number of patients with bronchiolitis requiring interhospital transfer from a community hospital to a PICU, though we were underpowered for this outcome. Patients who received weight-based flow with protocolized weaning had a shorter length of stay, which may reflect a clinical impact of weight-based flow or the efficacy of the aggressive weaning pathway.

UPDATE - 2022 Italian guidelines on the management of bronchiolitis in infants

Bronchiolitis is an acute respiratory illness that is the leading cause of hospitalization in young children. This document aims to update the consensus document published in 2014 to provide guidance on the current best practices for managing bronchiolitis in infants. The document addresses care in both hospitals and primary care. The diagnosis of bronchiolitis is based on the clinical history and physical examination. The mainstays of management are largely supportive, consisting of fluid management and respiratory support. Evidence suggests no benefit with the use of salbutamol, glucocorticosteroids and antibiotics with potential risk of harm. Because of the lack of effective treatment, the reduction of morbidity must rely on preventive measures. De-implementation of non-evidence-based interventions is a major goal, and educational interventions for clinicians should be carried out to promote high-value care of infants with bronchiolitis. Well-prepared implementation strategies to standardize care and improve the quality of care are needed to promote adherence to guidelines and discourage non-evidence-based attitudes. In parallel, parents' education will help reduce patient pressure and contribute to inappropriate prescriptions. Infants with pre-existing risk factors (i.e., prematurity, bronchopulmonary dysplasia, congenital heart diseases, immunodeficiency, neuromuscular diseases, cystic fibrosis, Down syndrome) present a significant risk of severe bronchiolitis and should be carefully assessed. This revised document, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of acute bronchiolitis.

High-Flow Oxygen and Other Noninvasive Respiratory Support Therapies in Bronchiolitis: Systematic Review and Network Meta-Analyses

OBJECTIVES

We present a systematic review on the effectiveness of noninvasive respiratory support techniques in bronchiolitis.

DATA SOURCES

Systematic review with pairwise meta-analyses of all studies and network meta-analyses of the clinical trials.

STUDY SELECTION

Patients below 24 months old with bronchiolitis who require noninvasive respiratory support were included in randomized controlled trials (RCTs), non-RCT, and cohort studies in which high-flow nasal cannula (HFNC) was compared with conventional low-flow oxygen therapy (LFOT) and/or noninvasive ventilation (NIV).

DATA EXTRACTION

Emergency wards and hospitalized patients with bronchiolitis.

DATA SYNTHESIS

A total of 3,367 patients were analyzed in 14 RCTs and 8,385 patients in 14 non-RCTs studies. Only in nonexperimental studies, HFNC is associated with a lower risk of invasive mechanical ventilation (MV) than NIV (odds ratio, 0.49; 95% CI, 0.42-0.58), with no differences in experimental studies. There were no differences between HFNC and NIV in other outcomes. HFNC is more effective than LFOT in reducing oxygen days and treatment failure. In the network meta-analyses of clinical trials, NIV was the most effective intervention to avoid invasive MV (surface under the cumulative ranking curve [SUCRA], 57.03%) and to reduce days under oxygen therapy (SUCRA, 79.42%), although crossover effect estimates between interventions showed no significant differences. The included studies show methodological heterogeneity, but it is only statistically significant for the reduction of days of oxygen therapy and length of hospital stay.

CONCLUSIONS

Experimental evidence does not suggest that high-flow oxygen therapy has advantages over LFOT as initial treatment nor over NIV as a rescue treatment.

Effect of flow rate on the end-expiratory lung volume in infants with bronchiolitis using high-flow nasal cannula evaluated through electrical impedance tomography

OBJECTIVES

To evaluate the effects of four flow rates on the functional residual capacity (FRC) and pulmonary ventilation distribution while using a high-flow nasal cannula (HFNC).

WORKING HYPOTHESIS

Our hypothesis is that flow rates below 1.5 L·kg^-1 ·min^-1 lead to FRC loss and respiratory distress.

STUDY DESIGN

A single-center, prospective clinical study.

PATIENT SELECTION

Infants diagnosed with acute viral bronchiolitis were given HFNC.

METHODOLOGY

Through a prospective clinical study, the effects of four different flow rates, 2.0, 1.5, 1.0, and 0.5 L·kg^-1 ·min^-1 , on FRC and the pulmonary ventilation pattern were evaluated using electrical impedance tomography. The impedance variation (delta Z), end-expiratory lung volume (EELZ), respiratory rate, heart rate, respiratory distress score, and saturation/fraction of inspired oxygen ratio (SpO₂ /F_I O₂ ), were also evaluated at each flow rate.

RESULTS

Among the 11 infants included, There was a decrease in respiratory distress score at a flow rate of 1.5 L·kg^-1 ·min^-1 (*p = 0.021), and at a flow rate of 2.0 L·kg^-1 ·min^-1 (**p = 0.003) compared to 0.5 L·kg^-1 ·min^-1 . There was also a small but significant increase in SpO₂ /FiO₂ at flow rates of 1.5 (*p = 0.023), and 2.0 L·kg^-1 ·min^-1 (**p = 0.008) compared to 0.5 L·kg^-1 ·min^-1 . There were no other significant changes in the clinical parameters. In the global EELZ measurements, there was a significant increase under a flow rate of 2.0 L·kg^-1 ·min^-1 as compared to 0.5 L·kg^-1 ·min^-1 (p = 0.03). In delta Z values, there were no significant variations between the different flow rates.

CONCLUSION

The ∆EELZ increases at the highest flow rates were accompanied by decreased distress scores and improved oxygenation.

Treatment of Pediatric Patients With High-Flow Nasal Cannula and Considerations for Oral Feeding: A Review of the Literature

PURPOSE

High-Flow Nasal Cannula (HFNC) has become an increasingly common means of noninvasive respiratory support in pediatrics and is being used in infants and children with respiratory distress both inside and outside of the intensive care units. Despite the widespread use of HFNC, there remains a paucity of data on optimal flow rates and its impact on morbidity, mortality, and desired outcomes. Given the scarcity of information in these critical areas, it is not surprising that guidelines for initiation of oral feeding do not exist. This review article will review HFNC mechanisms of action, its use in specific populations and settings, and finally what is known about initiation of feeding during this therapy.

CONCLUSIONS

The practice of withholding oral feeding solely, because of HFNC, is not supported in the literature at the time of this writing, but in the absence of safety data from clinical trials, clinicians should proceed with caution and consider patient-specific factors while making decisions about oral feeding. Well-controlled prospective clinical trials are needed for development of best practice clinical guidelines and attainment of optimal outcomes.

Efficacy and safety analysis of high-flow nasal cannula in children with bronchiolitis: a systematic review and meta-analysis

BACKGROUND

Oxygen therapy is one of the most common treatments for bronchiolitis, But traditional standard oxygen therapy is poorly tolerated by patients. Nasal continuous positive airway pressure (nCPAP) also has many contraindications. High-flow nasal cannula (HFNC), as a new method of adjunctive respiratory support, has received extensive attention in oxygen therapy in pediatric. In this meta-analysis, we evaluated the efficacy and safety of HFNC in the treatment of infant bronchiolitis.

METHODS

We searched PubMed, Web of Science, CNKI, GeenMedical, Wanfang, and Weipu using the following keywords: children with respiratory diseases, infant bronchiolitis, bronchiolitis treatment, HFNCs, warming and humidifying high-flow, nasal catheter oxygen inhalation, and conventional oxygen therapy. The publication time was set from the establishment of the database to October 2021. Selected articles were randomized controlled trial (RCT) studies in which the patients were less than 16 years old and the experimental group was treated with HFNCs, and the control group was treated with nCPAP or conventional oxygen. After extracting the data, the study subjects were divided into HFNC treatment and control groups. The Cochrane risk of bias tool was used to assess the quality of the included literature, and RevMan 5.30 was used for meta-analysis.

RESULTS

Seven articles met the inclusion criteria. All articles described random sequence generation, four articles reported on allocation concealment, only two articles reported on the double-blind method. All articles described the complete blinding of outcome evaluation bias, outcome data bias, selective reporting bias, and other risk biases. The HFNC treatment group included 436 children, 405 children treated with nCPAP or standard oxygen therapy were included in the control. The results showed that the failure rate [relative risk (RR) is 0.57, 95% CI: 0.43-0.76], respiratory rate [mean difference (MD) is -7.43, 95% CI: -8.42 to -6.43], and social function (MD is 0.76, 95% CI: -0.32 to 1.83) of HFNC-treated children with bronchiolitis were significantly different to that of the control group patients.

DISCUSSION

HFNC treatment provides the same improvement in arterial oxygen partial pressure as standard oxygen therapy or transnasal positive airway pressure treatment, but it is significantly better at improving the respiratory rate of children with bronchiolitis.

Survey of Current Institutional Practices in the Use of High-Flow Nasal Cannula for Pediatric Patients

OBJECTIVES

High-flow nasal cannula (HFNC) is an oxygen delivery device that provides heated humidified air with higher flow rates. The purpose of this survey is to look at institutional practice patterns of HFNC initiation, weaning, and disposition for pediatric patients across the United States.

METHODS

Survey was sent via electronic listservs to pediatric physicians in emergency medicine, hospital medicine, critical care, and urgent care. The questionnaire was divided into demographics and HFNC practices (initiation, management, and weaning). One response per institution was included in the analysis.

RESULTS

Two hundred twenty-four responses were included in the analysis, composed of 40% pediatric emergency medicine physicians, 46% pediatric hospitalists, 13% pediatric intensive care unit (PICU) physicians, and 1% pediatric urgent care physicians. Ninety-eight percent of the participants have HFNC at their institution. Thirty-seven percent of the respondents had a formal guideline for HFNC initiation. Nearly all guideline and nonguideline institutions report HFNC use in bronchiolitis. Guideline cohort is more likely to have exclusion criteria for HFNC (42% in the guideline cohort vs 17% in the nonguideline cohort; P < 0.001) and less frequently mandates PICU admissions once on HFNC (11% in the guideline cohort vs 56% in the nonguideline cohort; P < 0.001). Forty-six percent of guideline cohort had an objective scoring system to help determine the need for HFNC, and 73% had a weaning guideline.

CONCLUSIONS

Although there is general agreement to use HFNC in bronchiolitis, great practice variation remains in the initiation, management, and weaning of HFNC across the United States. There is also a discordance on PICU use when a patient is using HFNC.

Risk Factors Associated with Mechanical Ventilation in Critical Bronchiolitis

The American Academy of Pediatrics (AAP) recommends supportive care for the management of bronchiolitis. However, patients admitted to the intensive care unit with severe (critical) bronchiolitis define a unique group with varying needs for both non-invasive and invasive respiratory support. Currently, no guidance exists to help clinicians discern who will progress to invasive mechanical support. Here, we sought to identify key clinical features that distinguish pediatric patients with critical bronchiolitis requiring invasive mechanical ventilation from those that did not. We conducted a retrospective cohort study at a tertiary pediatric medical center. Children ≤2 years old admitted to the pediatric intensive care unit (PICU) from January 2015 to December 2019 with acute bronchiolitis were studied. Patients were divided into non-invasive respiratory support (NRS) and invasive mechanical ventilation (IMV) groups; the IMV group was further subdivided depending on timing of intubation relative to PICU admission. Of the 573 qualifying patients, 133 (23%) required invasive mechanical ventilation. Median age and weight were lower in the IMV group, while incidence of prematurity and pre-existing neurologic or genetic conditions were higher compared to the NRS group. Multi-microbial pneumonias were diagnosed more commonly in the IMV group, in turn associated with higher severity of illness scores, longer PICU lengths of stay, and more antibiotic usage. Within the IMV group, those intubated earlier had a shorter duration of mechanical ventilation and PICU length of stay, associated with lower pathogen load and, in turn, shorter antibiotic duration. Taken together, our data reveal that critically ill patients with bronchiolitis who require mechanical ventilation possess high risk features, including younger age, history of prematurity, neurologic or genetic co-morbidities, and a propensity for multi-microbial infections.

Predicting Flow Rate Escalation for Pediatric Patients on High Flow Nasal Cannula Using Machine Learning

Background: High flow nasal cannula (HFNC) is commonly used as non-invasive respiratory support in critically ill children. There are limited data to inform consensus on optimal device parameters, determinants of successful patient response, and indications for escalation of support. Clinical scores, such as the respiratory rate-oxygenation (ROX) index, have been described as a means to predict HFNC non-response, but are limited to evaluating for escalations to invasive mechanical ventilation (MV). In the presence of apparent HFNC non-response, a clinician may choose to increase the HFNC flow rate to hypothetically prevent further respiratory deterioration, transition to an alternative non-invasive interface, or intubation for MV. To date, no models have been assessed to predict subsequent escalations of HFNC flow rates after HFNC initiation. Objective: To evaluate the abilities of tree-based machine learning algorithms to predict HFNC flow rate escalations. Methods: We performed a retrospective, cohort study assessing children admitted for acute respiratory failure under 24 months of age placed on HFNC in the Johns Hopkins Children's Center pediatric intensive care unit from January 2019 through January 2020. We excluded encounters with gaps in recorded clinical data, encounters in which MV treatment occurred prior to HFNC, and cases electively intubated in the operating room. The primary study outcome was discriminatory capacity of generated machine learning algorithms to predict HFNC flow rate escalations as compared to each other and ROX indices using area under the receiver operating characteristic (AUROC) analyses. In an exploratory fashion, model feature importance rankings were assessed by comparing Shapley values. Results: Our gradient boosting model with a time window of 8 h and lead time of 1 h before HFNC flow rate escalation achieved an AUROC with a 95% confidence interval of 0.810 ± 0.003. In comparison, the ROX index achieved an AUROC of 0.525 ± 0.000. Conclusion: In this single-center, retrospective cohort study assessing children under 24 months of age receiving HFNC for acute respiratory failure, tree-based machine learning models outperformed the ROX index in predicting subsequent flow rate escalations. Further validation studies are needed to ensure generalizability for bedside application.

Current practices and policies regarding the use of high-flow nasal cannula on general pediatric inpatient wards in Canada

OBJECTIVES

High-flow nasal cannula (HFNC) oxygen therapy has become a common treatment for respiratory conditions in children. To our knowledge, no study has described practice patterns for HFNC on pediatric inpatient wards in Canada. The aim of this study was to survey current practices and policies regarding the use of HFNC on the ward in children's hospitals in Canada.

METHODS

We conducted a web-based survey of Pediatric Hospital Medicine section chiefs in major tertiary care hospitals in Canada. The primary outcome was the proportion of hospitals that use HFNC on the general pediatric ward. Secondary outcomes included indications for HFNC, initial and maximum flow rates, maximum FiO2, method of nutrition delivery while on HFNC, level of nursing and respiratory therapist care required, criteria for pediatric intensive care unit transfer, and subjective successes and challenges of implementing a ward-based HFNC policy.

RESULTS

The section chief survey response rate was 100% (15/15). Eight centres (53%) allowed the use of HFNC outside of an intensive care setting. Six centres initiated HFNC on the ward, while two centres only accepted patients after HFNC had been initiated in an intensive care setting. Other practices and policies varied considerably from centre to centre.

CONCLUSION

Our study reveals that approximately half of tertiary children's hospitals in Canada currently use HFNC on the ward and utilize a range of practices and policies. Other centres are considering implementation. Further research is needed to inform best practices for HFNC therapy, support stewardship of health care resources, and promote safe patient care.

Indications and Safety of High Flow Nasal Cannula in Pediatric Intensive Care Unit: Retrospective Single Center Experience in Saudi Arabia

Background

High flow nasal cannula (HFNC) is a new device for respiratory support. Its use continues to increase in pediatrics as its system is easily set up and well tolerated by patients. We aimed in this study to explore indications and safety of HFNC use and predictors of HFNC failure.

Methods

Hospital records of 92 children with acute respiratory distress admitted to the pediatric intensive care unit (PICU) in Abha Maternity and Children Hospital from January 2018 until March 2020 and received HFNC therapy were studied. A data collection sheet was used that included patients’ age, gender, the indication of HFNC, associated chronic diseases, previous admission to PICU, vital signs (initially, 8 hours and 48 hours after using HFNC), outcome after using HFNC, and reasons for HFNC failure.

Results

After receiving HFNC, children’s respiratory rate, heart rate, systolic blood pressure, and oxygen saturation improved significantly (p < 0.001, p < 0.001, p < 0.001, p = 0.005, and p < 0.001, respectively). Regarding laboratory findings, pH and serum bicarbonate improved significantly (p < 0.001 for both), while PaCO2 improved but not significantly. The failure rate of HFNC was 23.0%. HFNC failure rates were significantly higher among children with chronic diseases than those with no chronic disease (33.3% and 14.9%, respectively, p = 0.038) and among children with the air-leak syndrome (p < 0.001). After 48 hours of HFNC use, children who experienced HFNC failure had significantly higher respiratory and heart rates (p < 0.001 and p = 0.018, respectively), lower diastolic blood pressure (p = 0.011), and higher PaCO2 (p < 0.001).

Conclusion

After HFNC use, significant improvements occur in all clinical parameters and laboratory values of children with respiratory distress, but about one-fourth of cases may experience HFNC failure. Predictors for HFNC failure include underlying chronic disease, low diastolic blood pressure, high respiratory rate, high heart rate, high initial PaCO2.

Velocity-based target flow rate for high-flow nasal cannula oxygen therapy

BACKGROUND

The aim of this study was to assess retrospectively whether the average inspiratory flow velocity-based initial flow rate in high-flow nasal cannula (HFNC) therapy could be well tolerated and safely used for infants and children hospitalized with moderate to severe respiratory failure.

METHODS

Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO₂ ) >50 mmHg or venous blood pH <7.320, combined with pulse oximetry arterial oxygen saturation <92%, were included. We set target flow rates calculated from the average inspiratory flow velocity, starting at the actual initial flow rates, and these were subsequently adjusted if necessary.

RESULTS

One patient could not tolerate the cannula. Of the remaining 32 patients, 81% (n = 26) had an actual initial flow rate within 1 L of the target flow rate; these patients were evaluated for changes in the fraction of inspired oxygen (FITarget flow rate tableO₂ ), pH, and pCO₂ values after 24 h. Three patients required a higher fraction of inspired oxygen, one showed a persistent pH < 7.320, and seven exhibited pCO₂ >50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient.

CONCLUSIONS

The average inspiratory flow velocity-based initial flow rate was well-tolerated without sedation, and there were no severe complications. Starting at this flow rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.

Efficacy and safety of high flow nasal oxygen for children with bronchiolitis: systematic review and meta-analysis

BACKGROUND

To assess the published evidence to establish the efficacy and safety of high flow oxygen cannula (HFNC) as respiratory support for children up to 24 months of age with bronchiolitis within acute hospital settings.

METHODS

We searched eight databases up to March 2021. Studies including children up to 24 months of age with a diagnosis of bronchiolitis recruited to an randomised controlled trial were considered in the full meta-analysis. At least one arm of the study must include HFNC as respiratory support and report at least one of the outcomes of interest. Studies were identified and extracted by two reviewers. Data were analysed using Review Manager V.5.4.

RESULTS

From 2943 article titles, 308 full articles were screened for inclusion. 23 studies met the inclusion criteria, 15 were included in the metanalyses. Four studies reported on treatment failure rates when comparing HFNC to standard oxygen therapy (SOT). Data suggests HFNC is superior to SOT (OR 0.45, 95% CI 0.36 to 0.57). Four studies reported on treatment failure rates when comparing HFNC to continuous positive airways pressure (CPAP). No significant difference was found between CPAP and HFNC (OR 1.64, 95% CI 0.96 to 2.79; p=0.07). Four studies report on adverse outcomes when comparing HFNC to SOT. No significant difference was found between HFNC & SOT (OR 1.47, 95% CI 0.54 to 3.99).

CONCLUSION

HFNC is superior to SOT in terms of treatment failure and there is no significant difference between HFNC and CPAP in terms of treatment failure. The results suggest HFNC is safe to use in acute hospital settings.

A multicentered study on efficiency of noninvasive ventilation procedures (SAFE-NIV)

Background/aim

To characterize the clinical course of noninvasive positive pressure ventilation (NIPPV) and high flow humidified nasal cannula ventilation (HFNC) procedures; perform risk analysis for ventilation failure.

Material and methods

This prospective, multi-centered, observational study was conducted in 352 PICU admissions (1 month-18 years) between 2016 and 2017. SPSS-22 was used to assess clinical data, define thresholds for ventilation parameters and perform risk analysis.

Results

Patient age, onset of disease, previous intubation and hypoxia influenced the choice of therapy mode: NIPPV was preferred in older children (p = 0.002) with longer intubation (p < 0.001), ARDS (p = 0.001), lower respiratory tract infections (p < 0.001), chronic respiratory disease, (p = 0.005), malignancy (p = 0.048) and immune deficiency (p = 0.026). The failure rate was 13.4%. sepsis, ARDS, prolonged intubation, and use of nasal masks were associated with NIV failure (p = 0.001, p < 0.001, p < 0.001, p = 0.025). The call of intubation or re-intubation was given due to respiratory failure in twenty-seven (57.5%), hemodynamic instability in eight (17%), bulbar dysfunction or aspiration in 5 (10.6%), neurological deterioration in 4 (8.5%) and developing ARDS in 3 (6.4%) children. A reduction of less than 10% in the respiration within an hour increased the odds of failure by 9.841 times (OR: 9.841, 95% CI: 2.0021–48.3742). FiO2 > 55% at 6th hours and PRISM-3 >8 were other failure predictors. Of the 9.9% complication rate, the most common complication was pressure ulcerations (4.8%) and mainly observed when using full-face masks (p = 0.047). Fifteen (4.3%) patients died of miscellaneous causes. Tracheostomy cannulation was performed on 16 children due to prolonged mechanical ventilation (8% in NIPPV, 2.6% in HFNC)

Conclusion

Absence of reduction in the respiration rate within an hour, FiO2 requirement >55% at 6th hours and PRISM-3 score >8 predict NIV failure.

High-flow nasal cannula failure: can clinical outcomes determine early interruption?

OBJECTIVE

To evaluate the evolution of clinical outcomes in children with bronchiolitis who used a high-flow nasal cannula, and to determine after long of non-clinical improvement the therapy should be discontinued, and treatment should be escalated to other forms of ventilatory support.

METHODS

An observational retrospective study of infants with bronchiolitis who used a high-flow nasal cannula. Patients were divided into two study groups according to success or failure of high-flow nasal cannula therapy, namely the Success Group and the Failure Group. The main demographics and clinical variables were assessed 30 minutes and 6 hours after initiating therapy until removal of the high-flow nasal cannula.

RESULTS

A total of 83 children were studied and 18 children (21.7%) failed therapy. Among subjects with successful therapy, a significant decrease in respiratory rate (p<0.001), and a significant increase in peripheral oxygen saturation (p<0.001) were observed within 30 minutes. The Success Group was significantly different from the Failure Group after 6 hours, for both respiratory rate (p<0.01) and peripheral oxygen saturation (p<0.01).

CONCLUSION

The absence of clinical sign improvement within 30 minutes and for up to a maximum of 6 hours can be considered as failure of the high-flow nasal cannula therapy. If this time elapses with no improvements, escalating to another type of ventilatory support should be considered.

High-flow oxygen nasal cannula for treating acute bronchiolitis in infants: A systematic review and meta-analysis

Introduction

Oxygen therapy through a high-flow nasal cannula is thought to improve the work of breathing and the comfort of patients with acute bronchiolitis. It is widely used in hospital wards and critical care of pediatric patients. However, there is uncertainty on the magnitude of the effect on critical and important outcomes in these patients.

Objectives

The objective of this review is to evaluate the available evidence on the use of oxygen administered through high-flow cannula versus low-flow oxygen for the treatment of acute bronchiolitis in children under two years of age.

Methodology

We carried out a systematic review and a meta-analysis following the PRISMA standards for reporting. The search was carried out in electronic databases by two researchers independently. The evidence was summarized using the GRADE methodology.

Results

Six randomized and non-randomized clinical trials were included, including 1867 individuals younger than 24 months of age with acute bronchiolitis in pediatric emergency, hospitalization, and intensive care services. Mortality was not reported in the included studies. Treatment failure occurred in 108/933 in the high flow group and 233/934 in the low flow group (relative risk: 0.46; 95% confidence interval: 0.35 to 0.62), which shows 11.7% less treatment failure (95% confidence interval between 7.9% and 14.5% less) in the high flow group with a number needed to treat of 7.5 (95% confidence interval 6 to 10) with moderate certainty in the evidence.

Conclusion

The use of humidified and heated oxygen with high flow compared to oxygen at low flow is probably associated with decreased treatment failure in children younger than two years with acute bronchiolitis. There is uncertainty about the effect on hospitalization days and clinical progression.

Capillary blood gas in infants with bronchiolitis: Can end-tidal capnography replace it?

OBJECTIVES

To explore the predictive ability of capillary blood gas (CBG) pCO₂ for respiratory decompensation in infants aged ≤6 months with bronchiolitis admitted from the emergency department; to determine whether end-tidal CO₂ (etCO₂) capnography can serve as a less invasive substitute for CBG pCO₂.

STUDY DESIGN

This was a prospective cohort study of previously healthy infants aged ≤6 months admitted for bronchiolitis from the emergency department (ED). Initial CBG pCO₂ and etCO₂ capnography were obtained in the ED prior to inpatient admission. Simple logistic regression modeling was used to examine the associations of CBG pCO₂ and etCO₂ capnography with respiratory decompensation. Pearson's correlation measured the relationship between CBG pCO₂ and etCO₂ capnography.

RESULTS

Of 134 patients, 61 had respiratory decompensation. There was a significant association between CBG pCO₂ and respiratory decompensation (OR = 1.07, p = 0.003), even after outlying values were excluded (OR = 1.06, p = 0.005). End tidal CO₂ capnography was not significantly associated with decompensation (OR = 1.02, p = 0.17), even after outlying values were excluded (OR = 1.02, p = 0.24). There was a moderate correlation between etCO₂ capnography and CBG pCO₂ (r = 0.39, p < 0.001).

CONCLUSION

In infants with bronchiolitis, CBG pCO₂ provides an objective measure for predicting respiratory decompensation, and a single etCO₂ measurement should not replace its use.

Quality Initiative to Reduce High-Flow Nasal Cannula Duration and Length of Stay in Bronchiolitis

OBJECTIVES

High-flow nasal cannula (HFNC) use in bronchiolitis may prolong length of stay (LOS) if weaned more slowly than medically indicated. We aimed to reduce HFNC length of treatment (LOT) and inpatient LOS by 12 hours in 0- to 18-month-old patients with bronchiolitis on the pediatric hospital medicine service.

METHODS

After identifying key drivers of slow weaning, we recruited a multidisciplinary "Wean Team" to provide education and influence provider weaning practices. We then implemented a respiratory therapist-driven weaning protocol with supportive sociotechnical interventions (huddles, standardized orders, simplification of protocol) to reduce LOT and LOS and promote sustainability.

RESULTS

In total, 283 patients were included: 105 during the baseline period and 178 during the intervention period. LOT and LOS control charts revealed special cause variation at the start of the intervention period; mean LOT decreased from 48.2 to 31.2 hours and mean LOS decreased from 84.3 to 60.9 hours. LOT and LOS were less variable in the intervention period compared with the baseline period. There was no increase in PICU transfers or 72-hour return or readmission rates.

CONCLUSIONS

We reduced HFNC LOT by 17 hours and LOS by 23 hours for patients with bronchiolitis via multidisciplinary collaboration, education, and a respiratory therapist-driven weaning protocol with supportive interventions. Future steps will focus on more judicious application of HFNC in bronchiolitis.

High flow in children with respiratory failure: A randomised controlled pilot trial - A paediatric acute respiratory intervention study

AIMS

High-flow is increasingly used in children with acute hypoxaemic respiratory failure (AHRF), despite limited evidence. The primary feasibility endpoint for this pilot-study was the proportion of treatment failure, secondary outcomes being intensive care unit (ICU) admissions and proportion of patients requiring escalation of care. We measured duration of hospital stay, duration of oxygen therapy and rates of ICU admission.

METHODS

An open-labelled randomised controlled trial feasibility design was used in two tertiary children's hospitals in the emergency department and general wards. Children aged 0-16 years with AHRF were randomised (1:1) to either high-flow or standard-oxygen. Children on standard-oxygen received rescue high-flow in general wards if failure criteria were met.

RESULTS

Of 563 randomised, 283 received high-flow and 280 standard-oxygen with no adverse events. The proportion of children who failed treatment and receiving escalation of care was 11.7% (32/283 children) on high-flow and 18.1% (50/280 infants) on standard-oxygen (odds ratio 0.68, 95% confidence interval 0.38-1.00). In children with obstructive airway disease, 9.7% on high-flow and 17.4% on standard-oxygen required escalation (risk-difference -7.7% percentage points; 95% confidence interval -14.3, -1.1); in children with non-obstructive disease no difference was observed. Neither difference in ICU admissions nor any difference in length of hospital stay was observed. Sixty percent of children who failed standard-oxygen responded to rescue high-flow.

CONCLUSION

High-flow outside ICU appears to be feasible in children with AHRF and the required proportion of escalation was lower compared to standard-oxygen. The trial design can be applied in a future large randomised controlled trial.

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.

Physiometric Response to High-Flow Nasal Cannula Support in Acute Bronchiolitis

OBJECTIVES

To describe the rate of high-flow nasal cannula (HFNC) nonresponse and paired physiometric responses (changes [∆] in heart rate [HR] and respiratory rate [RR]) before and after HFNC initiation in hospitalized children with bronchiolitis.

METHODS

We performed a single-center, prospective descriptive study in a PICU within a quaternary referral center, assessing children aged ≤2 years admitted for bronchiolitis on HFNC from November 2017 to March 2020. We excluded for cystic fibrosis, airway anomalies, pulmonary hypertension, tracheostomy, neuromuscular disease, congenital heart disease, or preadmission intubation. Primary outcomes were paired ∆ and %∆ in HR and RR before and after HFNC initiation. Secondary outcomes were HFNC nonresponse rate (ie, intubation or transition to noninvasive positive pressure ventilation). Analyses included χ², Student's t, Wilcoxon rank, and paired testing.

RESULTS

Of the 172 children studied, 56 (32.6%) experienced HFNC nonresponse at a median of 14.4 (interquartile range: 4.8-36) hours and 11 (6.4%) were intubated. Nonresponders had a greater frequency of bacterial pneumonia, but otherwise no major differences in demographics, comorbidities, or viral pathogens were noted. Responders experienced reductions in both %ΔRR (-17.1% ± 15.8% vs +5.3% ± 22.3%) and %ΔHR (-6.5% ± 10.5% vs 0% ± 10.9%) compared with nonresponders.

CONCLUSIONS

In this prospective, observational cohort study, we provide baseline data describing expected physiologic changes after initiation of HFNC for children admitted to the PICU for bronchiolitis. In our descriptive analysis, patients with comorbid bacterial pneumonia appear to be at additional risk for subsequent HFNC nonresponse.

Real-life study of the role of high-flow nasal cannula for bronchiolitis in children younger than 3 months hospitalised in general pediatric departments

We aimed to describe the real-life role of high-flow nasal cannula (HFNC) for bronchiolitis in infants under 3 months of age admitted to three general pediatric departments during the 2017-2018 epidemic period. We retrospectively assessed the clinical severity (Wang score) for every 24-h period of treatment (H0-H24 and H24-H48) according to the initiated medical care (HFNC, oxygen via nasal cannula, or supportive treatments only), the child's discomfort (EDIN score), and transfer to the pediatric intensive care unit (PICU). A total of 138 infants were included: 47±53 days old, 4661±851.9 g, 70 boys (50.7%), 58 with hypoxemia (42%), Wang score of 6.67±2.58, 110 (79.7%) staying for 48 consecutive hours in the same ward. During the H0-H24 period, only patients treated with HFNC had a statistically significant decrease in the severity score (n=21/110; -2 points, P=0.002) and an improvement in the discomfort score (n=15/63; -3.8 points, P<0.0001). There was no difference between groups during the H24-H48 period. The rate of admission to the PICU was 2.9% for patients treated for at least 24 h with HFNC (n=34/138, 44% with oxygen) versus 16.3% for the others (P=0.033). Early use of HFNC improves both clinical status and discomfort in infants younger than 3 months admitted for moderately severe bronchiolitis, whatever their oxygen status.

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

BACKGROUND

The aims of this study were to evaluate the outcomes of patients with severe bronchiolitis who received preemptive high-flow nasal cannula (HFNC) treatment according to the authors' protocol, and to identify potential baseline characteristics that might predict patients who will not benefit from HFNC.

METHODS

This was a retrospective chart review of patients with severe bronchiolitis, who received preemptive HFNC treatment according to the authors' protocol and who were admitted to the pediatric emergency department between January 1, 2015, and December 31, 2016.

RESULTS

Eighty-four patients in total were enrolled over the 2 year period. Twenty-three patients (27.3%) failed HFNC. Of these, four responded to non-invasive mechanical ventilation and 19 required subsequent invasive ventilation. According to logistic regression analysis, existence of a chronic condition, significant tachycardia, existence of dehydration, and a venous pH <7.30 at admission were found to be predictors of HFNC failure. There were no cases of pneumothorax or any other reported adverse effects related to HFNC therapy.

CONCLUSIONS

Preemptive HFNC treatment, complying with a preestablished protocol, might be a safe way to support patients with severe bronchiolitis in high-volume, resource-limited pediatric emergency departments. The existence of a chronic condition, significant tachycardia, dehydration, and a venous pH <7.30 at admission could be risk factors for preemptive HFNC treatment failure in severe bronchiolitis.

High-Flow Nasal Cannula Use Outside of the ICU Setting

OBJECTIVES

To describe the practice of high-flow nasal cannula (HFNC) use in the pediatric ward setting across North America.

METHODS

A survey was distributed through the Pediatric Research in Inpatient Settings Network, which represents 114 hospital sites. Questions included indication for HFNC use, flow and oxygen parameters, guideline availability, and use of outcomes measures.

RESULTS

There was a response rate of 68% to the survey from sites representing all regions from the United States. Thirty-seven sites (48%) used HFNC in the pediatric ward setting. All 37 sites used HFNC for patients with bronchiolitis. All children's hospital sites providing HFNC on the wards had an on-site ICU, compared with only 60% of non-children's hospital sites (P = .003). Seventy-six percent of sites used local protocols, including parameters for patient assessment, initiation, weaning, and feeding practices.

CONCLUSIONS

HFNC is used outside the ICU in nearly 50% of responding hospitals, with variation related to flow rate, feeding, and protocol use. HFNC is used for management of acute respiratory distress due to bronchiolitis, asthma, and pneumonia. Study findings suggest that HFNC is often used by pediatric hospitalists, but its use across North American hospitals remains variable and based on local consensus.

First-line oxygen therapy with high-flow in bronchiolitis is not cost saving for the health service

BACKGROUND

Bronchiolitis is the most common reason for hospital admission in infants. High-flow oxygen therapy has emerged as a new treatment; however, the cost-effectiveness of using it as first-line therapy is unknown.

OBJECTIVE

To compare the cost of providing high-flow therapy as a first-line therapy compared with rescue therapy after failure of standard oxygen in the management of bronchiolitis.

METHODS

A within-trial economic evaluation from the health service perspective using data from a multicentre randomised controlled trial for hypoxic infants (≤12 months) admitted to hospital with bronchiolitis in Australia and New Zealand. Intervention costs, length of hospital and intensive care stay and associated costs were compared for infants who received first-line treatment with high-flow therapy (early high-flow, n=739) or for infants who received standard oxygen and optional rescue high-flow (rescue high-flow, n=733). Costs were applied using Australian costing sources and are reported in 2016-2017 AU$.

RESULTS

The incremental cost to avoid one treatment failure was AU$1778 (95% credible interval (CrI) 207 to 7096). Mean cost of bronchiolitis treatment including intervention costs and costs associated with length of stay was AU$420 (95% CrI -176 to 1002) higher per infant in the early high-flow group compared with the rescue high-flow group. There was an 8% (95% CrI 7.5 to 8.6) likelihood of the early high-flow oxygen therapy being cost saving.

CONCLUSIONS

The use of high-flow oxygen as initial therapy for respiratory failure in infants with bronchiolitis is unlikely to be cost saving to the health system, compared with standard oxygen therapy with rescue high-flow.

Nasogastric tube, a warning sign for high-flow nasal cannula failure in infants with bronchiolitis

High-flow nasal cannula (HFNC) therapy is routinely used in the treatment of infants with bronchiolitis. This study sought to identify markers associated with failure of HFNC therapy that serve as warnings for early staging of other ventilatory support products. A retrospective study of infants with a diagnosis of bronchiolitis, receiving HFNC and admitted to the pediatric intensive care unit from January 2016 to June 2017, was conducted. The subjects were divided into two study groups according to the success or failure of HFNC therapy. Risk factors were assessed using the following variables: age, time between hospital admission and start of HFNC, equipment model, and the need for a nasogastric tube. Eighty-one infants were studied, and 18 (21.7%) of them exhibited therapy failure. The results of the logistic models showed that the chances of failure for patients requiring a nasogastric tube during HFNC use were more likely than those for patients with oral nutrition (OR = 8.17; 95% CI 2.30–28.99; p = 0.001). The HFNC failure was not associated with the device used (OR = 1.56; 95% CI 0.54–4.52; p = 0.41), time between hospital admission and HFNC installation (OR = 1.01; 95% CI 0.98–1.03; p = 0.73), or age (OR = 0.98; 95% CI 0.82–1.17; p = 0.82). Among late outcomes evaluated, the patients with therapy failure had longer total durations of O₂ use (p < 0.001) and longer hospital stays (p < 0.001). The need to use a nasogastric tube during HFNC use was associated with HFNC therapy failure and can be considered as a marker of severity in children with bronchiolitis.

A randomised trial of high-flow nasal cannula in infants with moderate bronchiolitis

BACKGROUND

The objective was to determine whether high-flow nasal cannula (HFNC), a promising respiratory support in infant bronchiolitis, could reduce the proportion of treatment failure requiring escalation of care.

METHODS

In this randomised controlled trial, we assigned infants aged <6 months who had moderate bronchiolitis to receive either HFNC at 3 L·kg^-1·min^-1 or standard oxygen therapy. Crossover was not allowed. The primary outcome was the proportion of patients in treatment failure requiring escalation of care (mostly noninvasive ventilation) within 7 days following randomisation. Secondary outcomes included rates of transfer to the paediatric intensive care unit (PICU), oxygen, number of artificial nutritional support-free days and adverse events.

RESULTS

The analyses included 268 patients among the 2621 infants assessed for inclusion during two consecutive seasons in 17 French paediatric emergency departments. The percentage of infants in treatment failure was 14% (19 out of 133) in the study group, compared to 20% (27 out of 135) in the control group (OR 0.66, 95% CI 0.35-1.26; p=0.21). HFNC did not reduce the risk of admission to PICU (21 (15%) out of 133 in the study group versus 26 (19%) out of 135 in the control group) (OR 0.78, 95% CI 0.41-1.41; p=0.45). The main reason for treatment failure was the worsening of modified Wood clinical asthma score (m-WCAS). Short-term assessment of respiratory status showed a significant difference for m-WCAS and respiratory rate in favour of HFNC. Three pneumothoraces were reported in the study group.

CONCLUSIONS

In patients with moderate bronchiolitis, there was no evidence of lower rate of escalating respiratory support among those receiving HFNC therapy.

Intensive Care Unit Utilization After Adoption of a Ward-Based High-Flow Nasal Cannula Protocol

BACKGROUND

Hospitals are increasingly adopting ward-based high-flow nasal cannula (HFNC) protocols that allow HFNC treatment of bronchiolitis outside of the intensive care unit (ICU). Our objective was to determine whether adoption of a ward-based HFNC protocol reduces ICU utilization.

METHODS

We examined a retrospective cohort of infants aged 3 to 24 months hospitalized with bronchiolitis at hospitals in the Pediatric Health Information System database. The study exposure was adoption of a ward-based HFNC protocol, measured by direct contact with pediatric hospital medicine leaders at each hospital. All analyses utilized an interrupted time series approach. The primary analysis compared outcomes three respiratory seasons before and three respiratory seasons after HFNC adoption, among adopting hospitals. Supplementary analysis 1 mirrored the primary analysis with the exception that the first season after adoption was censored. In supplementary analysis 2, effects among nonadopting hospitals were subtracted from effects measured among adopting hospitals.

RESULTS

Of 44 contacted hospitals, 41 replied (93% response rate), of which 18 were categorized as non-adopting hospitals and 12 were categorized as adopting hospitals. Included ward-based HFNC protocols were adopted between the 2010-2011 and 2015-2016 respiratory seasons. The primary analysis included 26,253 bronchiolitis encounters and measured immediate increases in the proportion of patients admitted to the ICU (absolute difference, 3.1%; 95% CI, 2.8%-3.4%) and ICU length of stay (absolute difference, 9.1 days per 100 patients; 95% CI, 5.1-13.2). Both supplementary analyses yielded similar findings.

CONCLUSION

Early protocols for ward-based HFNC were paradoxically associated with increased ICU utilization.

Enteral hydration in high-flow therapy for infants with bronchiolitis: Secondary analysis of a randomised trial

AIM

Nasal high-flow oxygen therapy is increasingly used in infants for supportive respiratory therapy in bronchiolitis. It is unclear whether enteral hydration is safe in children receiving high-flow.

METHODS

We performed a planned secondary analysis of a multi-centre, randomised controlled trial of infants aged <12 months with bronchiolitis and an oxygen requirement. Children were assigned to treatment with either high-flow or standard-oxygen therapy with optional rescue high-flow. We assessed adverse events based on how children on high-flow were hydrated: intravenously (IV), via bolus or continuous nasogastric tube (NGT) or orally.

RESULTS

A total of 505 patients on high-flow via primary study assignment (n = 408), primary treatment (n = 10) or as rescue therapy (n = 87) were assessed. While on high flow, 15 of 505 (3.0%) received only IV fluids, 360 (71.3%) received only enteral fluids and 93 (18.4%) received both IV and enteral fluids. The route was unknown in 37 (7.3%). Of the 453 high-flow infants hydrated enterally patients could receive one or more methods of hydration; 80 (15.8%) received NGT bolus, 217 (43.0%) NGT continuous, 118 (23.4%) both bolus and continuous, 32 (6.3%) received only oral hydration and 171 (33.9%) a mix of NGT and oral hydration. None of the patients receiving oral or NGT hydration on high-flow sustained pulmonary aspiration (0%; 95% confidence interval N/A); one patient had a pneumothorax (0.2%; 95% confidence interval 0.0-0.7%).

CONCLUSIONS

The vast majority of children with hypoxic respiratory failure in bronchiolitis can be safely hydrated enterally during the period when they receive high-flow.

High flow nasal cannula as respiratory support in treating infant bronchiolitis: a systematic review

Bronchiolitis is a common respiratory illness in early childhood, often leading to hospitalization and associated healthcare costs. Low flow 100% oxygen through nasal prongs is the standard therapy for infants with bronchiolitis and hypoxemia. Nasal continuous positive airway pressure (nCPAP) or invasive ventilation is used in case of progressive respiratory failure. High flow heated and humidified oxygen therapy with delivery of an air-oxygen mixture up to 2 L/min/kg body weight via nasal prongs (referred to as high flow nasal cannula or HFNC) is a newer method for respiratory support. Initial data from retrospective studies were promising but should be interpreted with caution. A limited number of prospective randomized controlled trials (RCT) have now compared HFNC with either standard oxygen therapy (SOT) or nCPAP. In this review, we critically summarize the data from these RCTs with the aim to provide advice on how to position HFNC in clinical practice.Conclusion: HFNC is a safe mode of respiratory support that can be positioned between SOT and nCPAP as rescue therapy for children not adequately supported by SOT. It does not seem to shorten the duration of oxygen need nor the duration of hospital admission.What is Known:• HFNC is being used increasingly in the context of infant bronchiolitis. However, evidence on efficacy and safety are limited. Different published studies involve different disease severities and different pediatric settings.What is New:• In this review, we summarize data only from prospective RCTs with the aim to provide guidance on how to use HFNC.

High flow nasal cannula and continuous positive airway pressure therapy in treatment of viral bronchiolitis: a randomized clinical trial

Continuous positive airway pressure (CPAP) has been used in infants with bronchiolitis for decades. Recently, high flow nasal cannula (HFNC) therapy was introduced. We conducted a trial of 50 children with bronchiolitis who were randomized to treatment with CPAP or HFNC. Objectives were to compare the development in respiratory rate, pCO2, and Modified Woods Clinical Asthma Score (M-WCAS) in young children with bronchiolitis, treated with CPAP or HFNC. Secondarily, to compare Neonatal Infant Pain Score (NIPS), treatment duration, treatment failure, and hospitalization length. Median age at inclusion was 2.8 (CPAP group) vs 2.1 months (HFNC group). Mean baseline pCO2 was 6.7 in both groups and mean respiratory rate was 60 vs 56 in the CPAP and HFNC group respectively. No differences were observed in development of respiratory rate, pCO2, or M-WCAS. NIPS was higher in the CPAP group. Treatment failure was scarce in both groups. No significant differences in treatment duration or length of hospitalization were observed.Conclusion: In infants and young children with bronchiolitis, HFNC may be an effective and pleasant alternative to CPAP. Larger multicenter studies are needed to further explore differences in treatment failure and treatment duration.Trial registration: www.clinicaltrial.gov. id NCT02618213, registration date December 1, 2015.What is Known:• CPAP has been used for many years for respiratory support in infant bronchiolitis. The method requires special staff skills and may be stressful to the child.• HFNC has been introduced as a newer tool.What is New:• In infants with bronchiolitis, HFNC and CPAP were comparable in decreasing respiratory rate, pCO2, and need for oxygen supply.• Pain score during therapy was lower in the HFNC group.

The Role of Viral Coinfection in Bronchiolitis Treated With High-Flow Nasal Cannula at Pediatric Emergency Department During 2 Consecutive Seasons: An Observational Study

BACKGROUND

The role of multiple respiratory viruses in bronchiolitis treated with high-flow nasal cannula (HFNC) has not been thoroughly investigated. We evaluated the contribution of coinfection on clinical course of bronchiolitis treated with HFNC and on response to this treatment.

METHODS

We selected 120 children with bronchiolitis, younger than 12 months, admitted to Emergency Department between 2016 and 2018 and treated with HFNC. We compared single and multiple virus infections in relation to specific outcomes such as the clinical response to HFNC and the HFNC failure. The multiple virus infection was defined by the detection of 2 or more viruses in nasopharyngeal aspirates. The HFNC failure was defined as escalation to higher level of care, including Helmet-Continuous Positive Airway Pressure, invasive ventilation or transfer to pediatric intensive care unit within 48 hours from the time of HFNC initiation. We also performed a comparison between HFNC failure and HFNC not-failure groups according to the number of virus and the type of virus.

RESULTS

The severity score post-HFNC initiation was significantly associated with coinfection [odds ratio (OR): 1.361; 95% confidence interval (CI): 1.036-1.786; P = 0.027]. The likelihood of coinfection decreased by 23.1% for each increase of saturation O2 after HFNC initiation (OR: 0.769; 95% CI: 0.609-0.972; P = 0.028). Atelectasis was more likely to occur in coinfection (OR: 2.923; 95% CI: 1.049-8.148; P = 0.04). The duration of HFNC treatment increased significantly in coinfection (OR: 1.018; 95% CI: 1.006-1.029; P = 0.002). No significant differences were described between HFNC failure and the number and the type of detected viruses.

CONCLUSIONS

The detection of multiple viruses and the type of virus did not influence the HFNC failure, although the coinfection was associated with a deterioration of severity score, a longer HFNC treatment and a major presence of atelectasis. The role of coinfection on HFNC treatment might subtend a complex interplay between multiple viruses and host susceptibility.

PICU Admission Rates in Pediatric Cancer and Hematopoietic Stem Cell Transplant Patients Receiving High-flow Nasal Cannula Oxygen Therapy on the General Ward

The use of high-flow nasal cannula (HFNC) oxygen therapy is growing as an alternative to standard oxygen. However, its use in patients treated for malignancies, including hematopoietic stem cell transplantation (HSCT) patients, is controversial. In this retrospective cohort study, we assessed outcomes of pediatric cancer and HSCT patients (including nonmalignant indications) with acute hypoxemic respiratory failure treated with HFNC on the ward. Among 39 patients included in the study, 53 episodes of HFNC treatment were analyzed. Of these episodes, 18 (34%) failed and patients required subsequently pediatric intensive care unit (PICU) admission. A significant median higher C reactive protein (175 [range, 72 to 308] vs. 80 [13.5 to 187.8] mg/dL; P=0.006) and higher Bedside Pediatric Early Warning Score (PEWS) 1 to 4 hours after initiation of HFNC (10.1±0.8 vs. 7.1±0.4; P=0.001) was found in the failure group compared with the nonfailure group. Among the 18 patients admitted to PICU, 14 (78%) needed intubation. Five (28%) patients died during their PICU admission. In summary, one third of the pediatric cancer and HSCT patients receiving HFNC on the ward eventually required PICU admission of which 78% were intubated. C reactive protein and BedsidePEWS 1 to 4 hours after initiation of HFNC were significantly associated with the need for PICU admission. However, no firm conclusion can be drawn whether HFNC treatment should actually be initiated in the ward in this vulnerable patient population. Larger, prospective studies are needed to evaluate the most appropriate treatment and setting (PICU or general ward) for these patients.

Use of high-flow nasal cannula in infants with viral bronchiolitis outside pediatric intensive care units

High-flow nasal cannula (HFNC) is frequently used in infants with acute viral bronchiolitis outside pediatric intensive care units (PICU). A structured questionnaire was sent out to pediatricians of all public French hospitals with pediatric emergency and/or general pediatric departments on their use of HFNC outside PICU (department using HFNC, number of available devices, monitoring, criteria for initiating or stopping HFNC, and personal comments on HFNC). Of the 166 eligible hospitals, 135 answered (96 general and 39 university hospitals; 81.3%), for a total of 217 answering pediatricians. Seventy-two hospitals (53.3%) used HFNC in acute bronchiolitis outside PICU, particularly, general hospitals (59.4% vs 38.5%), and mostly in pediatric general departments (75%). Continuous patient monitoring with a cardiorespiratory monitor was usual (n = 58, 80%). Nursing staff was responsible for 2.7 children on HFNC and checked vital signs 8.6 times per day. Criteria for HFNC initiation and withdrawal were not standardized. Pediatricians had a positive opinion of HFNC and were willing to extend its use to other diseases.Conclusion: Use of HFNC outside PICU in infants with acute bronchiolitis is now usual, but urgently requires guidelines. What is Known: • Acute viral bronchiolitis treatment is only supportive • High-flow nasal cannula (HFNC) is a respiratory support accumulating convincing clinical evidence in bronchiolitis • This latter treatment is usually proposed in pediatric intensive care unit (PICU) What is New: • HFNC are increasingly used outside PICU in bronchiolitis, particularly, in general hospitals and in pediatric general departments • Pediatricians are enthusiastic about this device, but validated criteria for initiation and withdrawal are lacking • Guidelines for the use of HFNC outside PICU are urgently required.

Feeding during High-Flow Nasal Cannula for Bronchiolitis: Associations with Time to Discharge

BACKGROUND

High-flow nasal cannula (HFNC) is increasingly used to treat children hospitalized with bronchiolitis; however, the best practices for feeding during HFNC and the impact of feeding on time to discharge and adverse events are unknown. The study objective was to assess whether feeding exposure during HFNC was associated with time to discharge or feeding-related adverse events.

METHODS

This retrospective cohort study included inpatients aged 1-24 months receiving HFNC for bronchiolitis at an academic children's hospital from January 1, 2015 to March 1, 2017. Feeding exposures during HFNC were categorized as fed or not fed. Among fed children, we further evaluated mixed (oral and tube) or exclusive oral feeding. The primary outcome was time to discharge after HFNC cessation. Secondary outcomes were aspiration, intubation after HFNC, and seven-day readmission.

RESULTS

Of 123 children treated with HFNC, 45 (37 %) were never fed. A total of 78 children (63%) were fed; 50 (41%) were exclusively orally fed and 28 (23 %) had mixed feeding. Median (interquartile range) time to discharge after HFNC was 29.5 hours (23.5-47.9) and 39.8 hours (26.4-61.5) hours in the fed and not fed groups, respectively. In adjusted models, time to discharge was shorter with any feeding (hazard ratio [HR] 2.17; 95% CI: 1.34-3.50) and with exclusive oral feeding (HR 2.13; 95% CI: 1.31-3.45) compared with no feeding. Time to discharge from HFNC initiation was shorter for exclusive oral feeding versus not feeding (propensity weighted HR 1.97 [95% CI: 1.13-3.43]). Adverse events (one intubation, one aspiration pneumonia, one readmission) occurred in both groups.

LIMITATIONS

Assessment of feeding exposure did not account for quantity and duration.

DISCUSSION

Children fed while receiving HFNC for bronchiolitis may have shorter time to discharge than those not fed. Feeding-related adverse events were rare regardless of the feeding method. Controlled prospective studies addressing residual confounding are needed to justify a change in the current practice.

'Rational use of high-flow therapy in infants with bronchiolitis. What do the latest trials tell us?' A Paediatric Research in Emergency Departments International Collaborative perspective

Bronchiolitis is the most common reason for infants to be hospitalised. Over the past decade, the use of high-flow nasal cannulae (HFNC) therapy has increased markedly and it is now utilised not only in the intensive care unit setting but in general paediatric wards and emergency departments. The aim of this systematic review was to summarise and critique the current evidence-base for the use of HFNC in infants with bronchiolitis. We searched Ovid Medline, OvidEmbase, PubMed, Cinahl, Cochrane Library, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials for systematic reviews and randomised controlled trials of HFNC therapy in infants with bronchiolitis from 1 January 2000 to 27 June 2018. We identified four randomised controlled trials (n = 1891) of HFNC in infants with bronchiolitis: three of these studies involved infants treated in emergency departments and inpatient paediatric wards in Spain, Australia and New Zealand, and one study involved infants treated in paediatric intensive care units in France. The findings of this review suggest that HFNC should be used as a rescue treatment for hypoxaemic infants who have not responded to standard sub nasal oxygen therapy. The use of HFNC for work of breathing in the absence of hypoxaemia, and severe disease, is not currently supported by the evidence, and should only be considered in the context of an appropriate research trial.

Comparison of heated humidified high-flow nasal cannula flow rates (1-L·kg·min-1 vs 2-L·kg·min -1 ) in the management of acute bronchiolitis

OBJECTIVE

We aimed to compare the heated humidified high-flow nasal cannula (HHHFNC) flow rate of 1-L·kg·min^-1 (1 L) with 2-L·kg·min ^-1 (2 L) in patients with severe bronchiolitis presenting to the pediatric emergency department.

STUDY DESIGN

We performed a study in which all patients were allocated to receive these two flow rates. The primary outcome was admitted as treatment failure, which was defined as a clinical escalation in respiratory status. Secondary outcomes covered a decrease of respiratory rate (RR), heart rate (HR), the clinical respiratory score (CRS), rise of peripheral capillary oxygen saturation (SpO₂ ), and rates of weaning, intubation, and intensive care unit (ICU) admission.

RESULTS

One hundred and sixty-eight cases (88 received the 1-L flow rate and 80, the 2-L flow rate) were included in the analyses. Treatment failure was 11.4% (10 of 88) in the 1-L group, and 10% (8 of 80) in the 2-L group (P = .775). Significant variation in the intubation rate or the ICU admission rate was not determined. At the 2nd hour, the rate of weaning (53.4% vs 35%; P = .017), the falling down of the CRS (-2.1 vs -1.5; P < .001), RR (-15.2 vs -11.8; P < .001), and HR (- 24.8 vs - 21.2; P < .001), and the increase of SpO ₂ (4.8 vs 3.6; P < .001) were significantly more evident in the 1-L group.

CONCLUSION

HHHFNC with the 1-L·kg·min^-1 flow rate, which provides a more frequent earlier effect, reached therapy success as high as the 2-L·kg·min ^-1 flow rate in patients with severe acute bronchiolitis.

High-flow nasal cannula therapy for children with bronchiolitis: a systematic review and meta-analysis

OBJECTIVES

To review the effects and safety of high-flow nasal cannula (HFNC) for bronchiolitis.

METHODS

Six electronic databases including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, CQ VIP Database and Wanfang Data were searched from their inception to 1 June 2018. Randomised controlled trials (RCTs) which investigated the effects of HFNC versus other forms of oxygen therapies for bronchiolitis were included.

RESULTS

Nine RCTs with 2121 children met the eligibility criteria. There was no significant difference in length of stay in hospital (LOS), length of oxygen supplementation (LOO), transfer to intensive care unit, incidence of intubation, respiratory rate, SpO₂ and adverse events in HFNC group compared with standard oxygen therapy (SOT) and nasal continuous positive airway pressure (nCPAP) groups. A significant reduction of the incidence of treatment failure (risk ratio (RR) 0.50, 95% CI 0.40 to 0.62, p<0.01) was observed in HFNC group compared with SOT group, but there was a significant increase of the incidence of treatment failure (RR 1.61, 95% CI 1.06 to 2.42, p0.02) in HFNC group compared with nCPAP group. In subgroup analysis, LOS was significantly decreased in HFNC group compared with SOT group in low-income and middle-income countries.

CONCLUSION

The systematic review suggests HFNC is safe as an initial respiratory management, but the evidence is still lacking to show benefits for children with bronchiolitis compared with SOT or nCPAP.

[What is the optimal flow on starting high-flow oxygen therapy for bronchiolitis treatment in paediatric wards?]

INTRODUCTION

High-flow nasal cannula (HFNC) is a safe and effective treatment in bronchiolitis in paediatric wards. The optimal flow on starting HFNC is still unknown. The main aim of this study was to determine if there were differences in clinical outcome of patients according the initial flow.

METHODS

A prospective, observational and analytical study was conducted between 2014 and 2016 on infants admitted with bronchiolitis and who required HFNC. Two cohorts were established according to the initial flow: cohort1: flow 15L/min (HFNC-15), and cohort2: flow 10L/min (HFNC-10). Treatment failure was defined as the presentation of apnoea or the absence of clinical improvement in the first 12-24hours. Multivariate probabilistic models were built to identify predictive variables of treatment failure.

RESULTS

A total of 57 patients were included. The median age was 4months (IQR 2-13), and 54% received treatment with HFNC-10 and 46% with HFNC-15. In HFNC-15 cohort, respiratory rate (RR) decreased in the first hour, and in the HFNC-10 cohort in the first 6hours (P=.03). In HFNC-10 cohort, treatment failure rate was 71%, compared to 15% of HFNC-15 (P<.01). Admission to PICU was required in 35% of the HFNC-10 group vs 18% in HFNC-15 (P=.11). No adverse effects were found.

CONCLUSIONS

The use of HFNC 15L/min in bronchiolitis treatment in paediatric wards is safe and effective, achieves a faster improvement of respiratory rate and has a lower treatment failure rate.