The effect of high flow nasal cannula therapy on the work of breathing in infants with bronchiolitis

Impact of initial high flow nasal cannula flow rates on clinical outcomes in children with bronchiolitis

PURPOSE

Our aim was to evaluate the impact of the initial high flow nasal cannula (HFNC) flow rate on clinical outcomes in children with bronchiolitis.

METHODS

This secondary analysis of retrospective data included children <2 years who required HFNC for bronchiolitis between 10/01/2018-04/20/2019, and following implementation of a revised institutional bronchiolitis pathway between 10/01/2021-04/30/2022. The new pathway recommended weight-based initiation of HFNC at 1.5-2 L/kg/min. We evaluated the effect of low (<1.0 L/kg/min), medium (1-1.5 L/kg/min) and high (>1.5 L/kg/min) HFNC flow rates on need for positive pressure ventilation (PPV), intensive care unit (ICU) transfer, HFNC treatment time, and hospital length of stay (LOS).

RESULTS

The majority of the 885 included children had low initial flow rates (low [n = 450, 50.8%], medium [n = 332, 37.5%] and high [n = 103, 11.7%]). There were no significant differences in PPV (high: 7.8% vs. medium: 9.3% vs. low: 8.2%, p = 0.8) or ICU transfers (high: 4.9% vs. medium: 6.0% vs. low: 3.8%, p = 0.3). The low flow group had a significantly longer median HFNC treatment time (High: 29 [18, 45] vs. medium: 29 [16, 50] vs. low: 39 [25, 63], p < .001) and hospital LOS (High: 41 [27, 59] vs. medium: 42 [29, 66] vs. low: 50 (39, 75), p < .001). Logistic and linear regression models did not demonstrate any associations between HFNC flow rates and PPV or hospital LOS.

CONCLUSIONS

Initial HFNC flow rates were not associated with significant changes in clinical outcomes in children in children with bronchiolitis.

ROX (Respiratory rate-OXygenation) index to predict early response to high-flow nasal cannula therapy in infants with viral bronchiolitis

INTRODUCTION

High-flow nasal cannula (HFNC) is commonly used as first step respiratory support in infants with moderate-to-severe acute viral bronchiolitis (AVB). This device, however, fails to effectively manage respiratory distress in about a third of patients, and data are limited on determinants of patient response. The respiratory rate-oxygenation (ROX) index is a relevant tool to predict the risk for HFNC failure in adult patients with lower respiratory tract infections. The primary objective of this study was to assess the relationship between ROX indexes collected before and 1 h after HFNC initiation, and HFNC failure occurring in the following 48 h in infants with AVB.

METHOD

This is an ancillary study to the multicenter randomized controlled trial TRAMONTANE 2, that included 286 infants of less than 6 months with moderate-to-severe AVB. Collection of physiological variables at baseline (H0), and 1 h after HFNC (H1), included heart rate (HR), respiratory rate (RR), fraction of inspired oxygen (FiO2 ), respiratory distress score (modified Wood's Clinical Asthma Score [mWCAS]), and pain and discomfort scale (EDIN). ROX and ROX-HR were calculated asSpO 2 FiO 2 RR $\frac{\left(\frac{{\mathrm{SpO}}_{2}}{{\mathrm{FiO}}_{2}}\right)}{\mathrm{RR}}$ and100 × ROX HR $100\times \frac{\mathrm{ROX}}{\mathrm{HR}}$ , respectively. Predefined HFNC failure criteria included increase in respiratory distress score or RR, increase in discomfort, and severe apnea episodes. The accuracies of ROX, ROX-HR indexes and clinical variable to predict HFNC failure were assessed using receiver operating curve analysis. We analyzed predictive factors of HFNC failure using multivariate logistic regressions.

RESULT

HFNC failure occurred in 111 of 286 (39%) infants, and for 56 (50% of the failure) of them within the first 6 h. The area under the curve of ROX indexes at H0 and H1 were, respectively, 0.56 (95% confidence interval [CI] 0.48-0.63, p = 0.14), 0.56 (95% CI 0.49-0.64, p = 0.09). ROX-HR performances were better but remained poorly discriminant. HFNC failure was associated with higher mWCAS score at H1 (p < 0.01) and lower decrease in EDIN scale during the first hour of HFNC delivery (p = 0.02). In the multivariate analyses, age and mWCAS score were were found to be independent factors associated with HFNC failure at H0. At H1, weight and mWCAS were associated factors.

CONCLUSION

In this study, neither ROX index, nor physiological variables usually collected in infants with AVB had early discriminatory capacity to predict HFNC failure.

Effect Modifiers of the Association of High-Flow Nasal Cannula and Bronchiolitis Length of Stay

BACKGROUND AND OBJECTIVES

High-flow nasal cannula (HFNC) therapy for hospitalized children with bronchiolitis is associated with a longer length of stay (LOS) when used outside of the ICU. We sought to explore the association between HFNC and LOS to identify if demographic and clinical factors may modify the effect of HFNC usage on LOS.

METHODS

In this multicenter retrospective cohort study, we used a combination of hospital records and the Pediatric Health Information System. We included encounters from September 1, 2018 to March 31, 2020 for patients <2 years old diagnosed with bronchiolitis. Multivariable Poisson regression was performed for the association of LOS with measured covariates, including fixed main effects and interaction terms between HFNC and other factors.

RESULTS

Of 8060 included patients, 2179 (27.0%) received HFNC during admission. Age group, weight, complex chronic condition, initial tachypnea, initial desaturation, and ICU services were significantly associated with LOS. The effect of HFNC on LOS differed among hospitals (P < .001), with the estimated increase in LOS ranging from 32% to 139%. The effect of HFNC on LOS was modified by age group, initial desaturation, and ICU services, with 1- to 6-month-old infants, patients without initial desaturation, and patients without ICU services having the highest association between HFNC and LOS, respectively.

CONCLUSIONS

We identified multiple potential effect modifiers for the relationship between HFNC and LOS. The authors of future prospective studies should investigate the effect of HFNC usage on LOS in non-ICU patients without documented desaturation.

Quality Improvement to Reduce High-Flow Nasal Cannula Overuse in Children With Bronchiolitis

BACKGROUND

High-flow nasal cannula oxygen therapy (HFNC) is increasingly used to treat bronchiolitis. However, HFNC has not reduced time on supplemental oxygen, length of stay (LOS), or ICU admission. Our objective was to reduce HFNC use in children admitted for bronchiolitis from 41% to 20% over 2 years.

METHODS

Using quality improvement methods, our multidisciplinary team formulated key drivers, including standardization of HFNC use, effective communication, knowledgeable staff, engaged providers and families, data transparency, and high-value care focus. Interventions included: (1) standardized HFNC initiation criteria, (2) staff education, (3) real-time feedback to providers, (4) a script for providers to use with families about expectations during admission, (5) team huddle for patients admitted on HFNC to discuss necessity, and (6) distribution of a bronchiolitis toolkit. We used statistical process control charts to track the percentage of children with bronchiolitis who received HFNC. Data were compared with a comparison institution not actively involved in quality improvement work around HFNC use to ensure improvements were not secondary to the COVID-19 pandemic alone.

RESULTS

Over 10 months of interventions, we saw a decrease in HFNC use for patients admitted with bronchiolitis from 41% to 22%, which was sustained for >12 months. There was no change in HFNC use at the comparison institution. The overall mean LOS for children with bronchiolitis decreased from 60 to 45 hours.

CONCLUSIONS

We successfully reduced HFNC use in children with bronchiolitis, improving delivery of high-value and evidence-based care. This reduction was associated with a 25% decrease in LOS.

Extubation to High-Flow Nasal Cannula in Infants Following Cardiac Surgery: A Retrospective Cohort Study

High-flow nasal cannula (HFNC) therapy is commonly used in the pediatric intensive care unit (PICU) for postextubation respiratory support. This hypothesis-generating retrospective cohort study aimed to compare postextubation PICU length of stay in infants extubated to HFNC and low flow oxygen (LF) in PICU following cardiac surgery. Of 136 infants (newborn to 1 year) who were intubated and mechanically ventilated in PICU following cardiac surgery, 72 (53%) were extubated to HFNC and 64 (47%) to LF. Compared with patients extubated to LF, those extubated to HFNC had significantly longer durations of cardiopulmonary bypass (152 vs. 109 minutes; p  = 0.002), aortic cross-clamp (90 vs. 63 minutes; p  = 0.003), and invasive mechanical ventilation (3.2 vs. 1.6 days; p  < 0.001), although demographic and preoperative clinical variables were similar. No significant difference was observed in postextubation PICU length of stay between HFNC and LF groups in unadjusted analysis (3.3 vs. 2.6 days, respectively; p  = 0.19) and after controlling for potential confounding variables (F [1,125] = 0.17, p  = 0.68, R 2  = 0.16). Escalation of therapy was similar between HFNC and LF groups (8.3 vs. 14.1%; p  = 0.41). HFNC was effective as rescue therapy for six patients in the LF group requiring escalation of therapy. Need for reintubation was similar between HFNC and LF groups (8.3 vs. 4.7%; p  = 0.5). Although extubation to HFNC was associated with a trend toward longer postextubation PICU length of stay and was successfully used as rescue therapy for several infants extubated to LF, our results must be interpreted with caution given the limitations of our study.

Perspectives of Health Care Personnel on the Benefits of Bronchiolitis Interventions

OBJECTIVES

Many interventions in bronchiolitis are low-value or poorly studied. Inpatient bronchiolitis management is multidisciplinary, with varying degrees of registered nurse (RN) and respiratory therapist (RT) autonomy. Understanding the perceived benefit of interventions for frontline health care personnel may facilitate deimplementation efforts. Our objective was to examine perceptions surrounding the benefit of common inpatient bronchiolitis interventions.

METHODS

We conducted a cross-sectional survey of inpatient pediatric RNs, RTs, and physicians/licensed practitioners (P/LPs) (eg, advanced-practice practitioners) from May to December of 2021 at 9 university-affiliated and 2 community hospitals. A clinical vignette preceded a series of inpatient bronchiolitis management questions.

RESULTS

A total of 331 surveys were analyzed with a completion rate of 71.9%: 76.5% for RNs, 57.4% for RTs, and 71.2% for P/LPs. Approximately 54% of RNs and 45% of RTs compared with 2% of P/LPs believe albuterol would be "extremely or somewhat likely" to improve work of breathing (P < .001). Similarly, 52% of RNs, 32% of RTs, and 23% of P/LPs thought initiating or escalating oxygen in the absence of hypoxemia was likely to improve work of breathing (P < .001). Similar differences in perceived benefit were observed for steroids, nebulized hypertonic saline, and deep suctioning, but not superficial nasal suctioning. Hospital type (community versus university-affiliated) did not impact the magnitude of these differences.

CONCLUSIONS

Variation exists in the perceived benefit of several low-value or poorly studied bronchiolitis interventions among health care personnel, with RNs/RTs generally perceiving higher benefit. Deimplementation, educational, and quality improvement efforts should be designed with an interprofessional framework.

The COVID-19 Driving Force: How It Shaped the Evidence of Non-Invasive Respiratory Support

During the COVID-19 pandemic, the use of non-invasive respiratory support (NIRS) became crucial in treating patients with acute hypoxemic respiratory failure. Despite the fear of viral aerosolization, non-invasive respiratory support has gained attention as a way to alleviate ICU overcrowding and reduce the risks associated with intubation. The COVID-19 pandemic has led to an unprecedented increased demand for research, resulting in numerous publications on observational studies, clinical trials, reviews, and meta-analyses in the past three years. This comprehensive narrative overview describes the physiological rationale, pre-COVID-19 evidence, and results of observational studies and randomized control trials regarding the use of high-flow nasal oxygen, non-invasive mechanical ventilation, and continuous positive airway pressure in adult patients with COVID-19 and associated acute hypoxemic respiratory failure. The review also highlights the significance of guidelines and recommendations provided by international societies and the need for further well-designed research to determine the optimal use of NIRS in treating this 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.

Clinical review of high-flow nasal oxygen therapy in human and veterinary patients

Oxygen therapy is the first-line treatment for hypoxemic acute respiratory failure. In veterinary medicine this has traditionally been provided via mask, low-flow nasal oxygen cannulas, oxygen cages and invasive positive pressure ventilation. Traditional non-invasive modalities are limited by the maximum flow rate and fraction of inspired oxygen (FiO₂) that can be delivered, variability in oxygen delivery and patient compliance. The invasive techniques are able to provide higher FiO₂ in a more predictable manner but are limited by sedation/anesthesia requirements, potential complications and cost. High-flow nasal oxygen therapy (HFNOT) represents an alternative to conventional oxygen therapy. This modality delivers heated and humidified medical gas at adjustable flow rates, up to 60 L/min, and FiO₂, up to 100%, via nasal cannulas. It has been proposed that HFNOT improves pulmonary mechanics and reduces respiratory fatigue via reduction of anatomical dead space, provision of low-level positive end-expiratory pressure (PEEP), provision of constant FiO₂ at rates corresponding to patient requirements and through improved patient tolerance. Investigations into the use of HFNOT in veterinary patients have increased in frequency since its clinical use was first reported in dogs with acute respiratory failure in 2016. Current indications in dogs include acute respiratory failure associated with pulmonary parenchymal disease, upper airway obstruction and carbon monoxide intoxication. The use of HFNOT has also been advocated in certain conditions in cats and foals. HFNOT is also being used with increasing frequency in the treatment of a widening range of conditions in humans. Although there remains conflict regarding its use and efficacy in some patient groups, overall these reports indicate that HFNOT decreases breathing frequency and work of breathing and reduces the need for escalation of respiratory support. In addition, they provide insight into potential future veterinary applications. Complications of HFNOT have been rarely reported in humans and animals. These are usually self-limiting and typically result in lower morbidity and mortality than those associated with invasive ventilation techniques.

Clinical practice guidelines: management of severe bronchiolitis in infants under 12 months old admitted to a pediatric critical care unit

PURPOSE

We present guidelines for the management of infants under 12 months of age with severe bronchiolitis with the aim of creating a series of pragmatic recommendations for a patient subgroup that is poorly individualized in national and international guidelines.

METHODS

Twenty-five French-speaking experts, all members of the Groupe Francophone de Réanimation et Urgence Pédiatriques (French-speaking group of paediatric intensive and emergency care; GFRUP) (Algeria, Belgium, Canada, France, Switzerland), collaborated from 2021 to 2022 through teleconferences and face-to-face meetings. The guidelines cover five areas: (1) criteria for admission to a pediatric critical care unit, (2) environment and monitoring, (3) feeding and hydration, (4) ventilatory support and (5) adjuvant therapies. The questions were written in the Patient-Intervention-Comparison-Outcome (PICO) format. An extensive Anglophone and Francophone literature search indexed in the MEDLINE database via PubMed, Web of Science, Cochrane and Embase was performed using pre-established keywords. The texts were analyzed and classified according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. When this method did not apply, an expert opinion was given. Each of these recommendations was voted on by all the experts according to the Delphi methodology.

RESULTS

This group proposes 40 recommendations. The GRADE methodology could be applied for 17 of them (3 strong, 14 conditional) and an expert opinion was given for the remaining 23. All received strong approval during the first round of voting.

CONCLUSION

These guidelines cover the different aspects in the management of severe bronchiolitis in infants admitted to pediatric critical care units. Compared to the different ways to manage patients with severe bronchiolitis described in the literature, our original work proposes an overall less invasive approach in terms of monitoring and treatment.

Efficacy of high-flow nasal oxygenation compared with laryngeal mask airway in children undergoing ambulatory oral surgery under deep sedation: A randomized controlled non-inferiority trial

BACKGROUND

High-flow nasal oxygenation (HFNO) has been suggested as an alternative oxygenation method during procedural sedation. This randomized, non-inferiority trial evaluated the safety and efficacy of HFNO compared with laryngeal mask airway (LMA) in pediatric ambulatory oral surgery under deep sedation.

METHODS

In total, 120 children aged 2-7 years (weight: 10-30 kg) were equally assigned into two groups, namely, HFNO with propofol total intravenous anesthesia infusion (HFNO-IV) or LMA with propofol total intravenous anesthesia infusion (LMA-IV). The primary objective was to monitor carbon dioxide (CO2) accumulation during perioperative surgery. Secondary objectives included monitoring transcutaneous oxygen saturation, grade exposure to the surgical field, perioperative adverse events, or other events. The predefined non-inferiority margin was 7 mmHg. During the COVID-19 pandemic, a novel WeChat applet was implemented to gather follow-up data after discharge.

RESULTS

Non-inferiority could be declared for HFNO relative to LMA (mean difference in transcutaneous CO2 (TcCO2) = -1.4 mmHg, 95% CI: -2.9, 0.1 mmHg; P > 0.05). The pre-surgical TcCO2 of the HFNO-IV group (45.4 ± 4.5 mmHg) was similar to that of the LMA-IV group (44.0 ± 3.5 mmHg), within the clinically acceptable normal range. All the children maintained SpO2 levels of >97%. The surgical field exposure score of the HFNO group was significantly better than that of the LMA group. There was no significant difference between the two groups regarding risk or adverse events.

CONCLUSION

HFNO was not inferior to LMA for maintaining oxygenation and ventilation in patients undergoing pediatric ambulatory oral surgery under deep sedation under strict isolation from the oral cavity to the upper airway.

Impact of different nebulisation systems on patient comfort in bronchiolitis: a randomised controlled cross-over trial

OBJECTIVE

To test the hypothesis that greater comfort is achieved using a nebuliser integrated into a high-flow nasal cannula (nebulisation system integrated in high-flow nasal cannula (NHF)) than using a jet nebuliser (JN), and to explore differences in analgesia requirement and the possibility of feeding during nebulisation.

DESIGN

Randomised cross-over trial.

SETTING

Paediatric intensive care unit.

PATIENTS

Children aged <24 months diagnosed with bronchiolitis between November 2016 and May 2017.

INTERVENTIONS

Nebulisations using NHF and JN.

MAIN OUTCOME MEASURES

COMFORT-Behaviour Scale (CBS) and Numerical Rating Comfort Scale (NRSc) were used to measure comfort, and Numerical Rating Satisfaction Scale (NRSs) was used to assess satisfaction before, during and after nebulisation. Other variables included feeding, analgesia, need for being held and respiratory and heart rates.

RESULTS

Thirty-three children with 233 nebulisations were included in the study. The median age was 3.0 (IQR 2-9) months. Comfort and satisfaction were greater with NHF than with JN. The median staff-recorded CBS, NRSc and NRSs scores for NHF versus JN were 13 (IQR 9-15) vs 17 (IQR 13-23), 8 (IQR 7-0) vs 7 (IQR 4-8), and 4 (IQR 3-4) vs 2 (IQR 2-3), respectively; and caregiver-recorded scores were 12 (IQR 10-15) vs 19 (IQR 13-24), 9 (IQR 7-10) vs 4 (IQR 1-6), and 4 (IQR 3-4) vs 2 (IQR 1-3), respectively (p<0.001). Children who received NHF had lower cardiac and respiratory rates, needed to be held less often during therapy and required less analgesia (p<0.001).

CONCLUSION

Nebulisation through NHF appears to be a better alternative to JN in terms of comfort and satisfaction as well as making feeding possible during nebulisation.

Is implementation of a hospital pathway for high-flow nasal cannula initiation and weaning associated with reduced high-flow duration in bronchiolitis?

BACKGROUND

High-flow nasal cannula (HFNC) therapy is widely used for children with bronchiolitis, but its optimal role remains uncertain. Our institution created and later revised a clinical pathway guiding HFNC initiation and weaning.

METHODS

A retrospective review of 1690 bronchiolitis encounters was conducted. Trends in the duration of HFNC and hours spent weaning HFNC as proportions of the monthly hospital length of stay (LOS) for bronchiolitis, hospital LOS, and escalation of care were compared using interrupted time series (ITS) models across three study periods: Baseline (HFNC managed at provider discretion), Intervention 1 (pathway with initiation at 0.5 L/kg/min and escalation up to 2 L/kg/min), and Intervention 2 (revised pathway, initiation at the maximum rate of 2 L/kg/min). Both pathway iterations provided titration and weaning guidance. Maximum respiratory scores were used to adjust for case severity.

RESULTS

After adjustment for severity and time, both HFNC duration and HFNC weaning time (as a proportion of monthly LOS) decreased at the start of Intervention 1, but subsequently increased. During Intervention 2, both these measures trended downward, returning to baseline. Total LOS did not change in the baseline or intervention periods. Escalation of care did not differ from baseline to the end of Intervention 2.

CONCLUSION

Initiating HFNC at higher flow rates with weaning guidance for children hospitalized with bronchiolitis was associated with a reduction in HFNC duration without differences in LOS or escalation of care. These findings suggest that standardization through clinical pathways can limit HFNC duration in bronchiolitis.

Variation and Outcomes of Hospital-Level High-Flow Nasal Cannula Usage Outside of Intensive Care

OBJECTIVES

Bronchiolitis is a viral respiratory infection that can progress to acute respiratory failure. This study evaluated the variability of hospital-wide high-flow nasal cannula (HFNC) usage outside of the ICU and its association with length of stay (LOS) and cost among pediatric patients admitted with bronchiolitis.

METHODS

This study included patients <2 years old admitted with bronchiolitis between September 1, 2018 and March 31, 2019. Hospitals were divided into groups based on the proportion of patients among those who had never been in the ICU who received HFNC (non-ICU HFNC usage [NIHU]). We performed hierarchical mixed-model linear regression to estimate the association of NIHU with LOS and cost using multiplicative ratios (MR) and 95% confidence intervals (CI), both (1) unadjusted and (2) after adjusting for demographics, clinical characteristics, and individual utilization of HFNC and/or ICU.

RESULTS

Unadjusted LOS was longer for patients in moderate (MR 1.14; 95% CI 1.11-1.18) and high (MR 1.26; 95% CI 1.22-1.30) NIHU hospitals. Adjusted LOS was longer in moderate (MR 1.03; 95% CI 1.01-1.06), and high (MR 1.08; 95% CI 1.05-1.11) NIHU hospitals. Unadjusted total cost was higher for patients in moderate (MR 1.20; 95% CI 1.16-1.25) and high (MR 1.26; 95% CI 1.22-1.31) NIHU hospitals. Adjusted total cost was higher for patients in moderate (MR 1.05; 95% CI 1.03-1.08), and high (MR 1.05; 95% CI 1.02-1.08) NIHU hospitals.

CONCLUSIONS

In this study, increased NIHU is associated with increased LOS and total cost.

Bronchiolitis therapies and misadventures

Viral bronchiolitis, which is most commonly caused by an infection with the respiratory syncytial virus (RSV), can lead to respiratory difficulties in young children which may require hospitalization. Despite years of research and medical trials, the mainstay of bronchiolitis treatment remains supportive only. This review provides an overview of the history of different treatments for bronchiolitis, including those that failed, as well as new therapies that are under study. Future studies for the treatment of bronchiolitis should consider different age-groups, important subgroups (i.e., those with a prior history of wheezing, those with a family history of asthma and those with non-RSV viral etiologies) whose response to treatment may differ from that of the composite group.

Impact of High-Flow Nasal Cannula Oxygenation on the Prevention of Hypoxia During Endoscopic Retrograde Cholangiopancreatography in Elderly Patients: A Randomized Clinical Trial

BACKGROUND

Hypoxia is the most frequently occurring adverse effect during endoscopic retrograde cholangiopancreatography (ERCP) under sedation; thus, oxygen must be properly supplied to prevent a reduction of oxygen saturation. In this study, we intend to verify the preventive effect for hypoxia during ERCP, using a high-flow nasal cannula (HFNC), in elderly patients.

METHODS

As a multicenter prospective randomized trial, patients who underwent ERCP with propofol-based sedation were randomly assigned into two groups: Patients in the HFNC group were supplied with oxygen via an HFNC, and those in the standard nasal cannula group were supplied with oxygen via a low-flow nasal cannula. The co-primary end points were the lowest oxygen saturation rate and hypoxia during the overall procedure.

RESULTS

A total of 187 patients (HFNC group: 95; standard nasal cannula group: 92) were included in the analysis. Unexpected hypoxia events were more frequently observed among patients in the standard nasal cannula group than among patients in the HFNC group (13% vs. 4%, odds ratio 3.41, 95% confidence interval 1.06-11.00, p = 0.031). The mean of the lowest oxygen saturation rate during ERCP was significantly lower in the standard nasal cannula group than in the HFNC group (95% vs. 97%, p = 0.002).

CONCLUSION

Oxygen supplementation with an HFNC can prevent oxygen desaturation and hypoxia events in patients undergoing ERCP under sedation. Trial registration Clinical Research Information Service (CRIS; KCT0004960).

Randomized Trial to Compare Nasoduodenal Tube and Nasogastric Tube Feeding in Infants with Bronchiolitis on High-Flow Nasal Cannula

Objectives In this article, we aimed to determine if there is a difference in length of respiratory support between nasoduodenal (NDT) and nasogastric tube (NGT) feedings in patients with bronchiolitis on high-flow nasal cannula (HFNC).

Methods A single-center nonblinded parallel randomized control trial at a tertiary care hospital was designed. Pediatric patients ≤ 12 months old with bronchiolitis, on HFNC, requiring nutrition via a feeding tube were eligible. Patients were randomized to NGT or NDT and stratified into low- and high-risk groups. Length of respiratory support was the primary outcome. Secondary outcomes included length of stay, number of emesis events, maximum level of respiratory support, number of X-rays to confirm tube placement, number of attempts to place the tube by staff, adverse events during placement, instances of pediatric intensive care unit admission, and emergency room visits and hospital readmissions within 7 and 30 days after discharge.

Results Forty patients were randomized, 20 in each arm. There were no significant differences in baseline characteristics. We found no significant difference in length of respiratory support between the two groups (NGT 0.84 incidence rate ratio [0.58, 1.2], p = 0.34). None of the secondary outcomes showed significant differences. Each arm reported one adverse event: nasal trauma in the NGT group and pneumothorax in the NDT group.

Conclusion For infants with bronchiolitis on HFNC that need enteric tube feedings, we find no difference in duration of respiratory support or other clinically relevant outcomes for those with NGT or NDT. These results should be interpreted in the context of a limited sample size and an indirect primary outcome of length of respiratory support that may be influenced by other factors besides aspiration events.

High-Flow Nasal Cannula Oxygen Therapy: Physiological Mechanisms and Clinical Applications in Children

High-flow nasal cannula (HFNC) oxygen therapy has rapidly become a popular modality of respiratory support in pediatric care. This is undoubtedly due to its ease of use and safety, which allows it to be used in a wide variety of settings, ranging from pediatric intensive care to patients' homes. HFNC devices make it possible to regulate gas flow and temperature, as well as allowing some nebulized drugs to be administered, features very useful in children, in which the balance between therapeutic effectiveness and adherence to treatment is pivotal. Although the physiological effects of HFNC are still under investigation, their mechanisms of action include delivery of fixed concentration of oxygen, generation of positive end-expiratory pressure, reduction of the work of breathing and clearance of the nasopharyngeal dead space, while providing optimal gas conditioning. Nevertheless, current evidence supports the use of HFNC mainly in moderate-to-severe bronchiolitis, whereas for asthma exacerbations and breath sleeping disorders there is a lack of randomized controlled trials comparing HFNC to continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV), which are essentials for the identification of response and non-response predictors. In this regard, the development of clinical guidelines for HFNC, including flow settings, indications, and contraindications is urgently needed.

High-flow nasal cannula oxygen in children with bronchiolitis: A randomized controlled trial

OBJECTIVE

To determine whether high-flow nasal cannula oxygen (HFNCO) provided enhanced respiratory support in bronchiolitis than low-flow oxygen (LFO).

METHODS

We conducted a prospective, randomized controlled trial in children between 1 and 24 months diagnosed with moderate-to-severe bronchiolitis requiring oxygen therapy. Participants received LFO via face mask (6-10 L/min) or HFNCO (2 L/kg/min). Primary outcomes were the time that heart rate (HR) and respiratory rate (RR) return to their normal range for age and the time that baseline clinical respiratory score (CRS) regress to a lower severity score. Secondary outcomes were changes in HR, RR, and CRS over time, length of stay (LOS), duration of oxygen requirement, treatment failure, and adverse event (AE).

RESULTS

Eighty-seven children were enrolled (48 in LFO; 39 in HFNCO). The time that HR and RR baseline values reached their normal range for age was shorter in HFNCO therapy (2.0 h [1.0-4.0] vs. 12.0 h [2.0-24.0], and 4.0 h [2.0-12.0] vs. 24.0 h [4.0-48.0], respectively; p < 0.001); additionally, the improvement in CRS emerged more quickly in children treated with HFNCO (2.0 h [1.0-4.0] vs. 4.0 h [2.0-24.0]; p = 0.003). While the duration of oxygen requirement (19.0 h [4.0-30.0] vs. 29.5 h [14.0-45.7]; p = 0.009) and treatment failure (3% vs. 21%) was statistically lower in children who received HFNCO, there were no differences in LOS and AE between groups.

CONCLUSION

HFNCO may provide enhanced respiratory support with a notable improvement in HR, RR, and CRS than LFO. Comprehensive studies are needed to assess the clinical efficacy of HFNCO therapy.

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.

High Flow Nasal Cannula in the Pediatric Intensive Care Unit

INTRODUCTION

The use of high flow nasal cannula (HFNC) has become widely used in pediatric intensive care units (PICUs) throughout the world. The rapid adoption has outpaced the number of studies evaluating the safety and efficacy in a variety of pediatric diseases/conditions.

AREAS COVERED

This scoping review begins with the definition and mechanisms of action of HFNC and then follows with a review of the literature focused on studies performed on critically ill children cared for in the PICU. The Pubmed database was searched with a pediatric filter from the time period 2000 to 2021.

EXPERT OPINION

The rapid adoption of HFNC in PICUs has largely been driven by changes in institutional practices and small observational studies. There is a lack of adequately powered studies evaluating patient-centered outcomes, such as intubation rates, mortality, PICU and hospital length of stay. Given the wide variability in flow rates and clinical indications, more research is needed to better define effective flow rates for different disease states as well as markers of treatment success and failure. One particular entity that is poorly studied is the use of HFNC in those at risk for developing pediatric acute respiratory distress syndrome (PARDS).

Continuous Positive Airway Pressure vs. High Flow Nasal Cannula in children with acute severe or moderate bronchiolitis. A systematic review and Meta-analysis

OBJECTIVE

To compare the safety and effectiveness of Continuous Positive Airway Pressure (CPAP) vs. High Flow Nasal Cannula (HFNC) to prevent therapeutic failure and the need of invasive ventilation in children with acute moderate-severe bronchiolitis.

DESIGN

A systematic review and meta-analysis.

SETTING

Medline, Embase, Lilacs, Cochrane and gray literature (May 2020) was performed.

PARTICIPANTS

Randomized clinical trials patients with moderate to severe bronchiolitis.

MAIN VARIABLES

Therapeutic failure, need for invasive ventilation, adverse events, length of PCCU and of hospital stay.

INTERVENTION

The quality of the studies was assessed with the Cochrane risk and bias tool. We conducted meta-analysis using fixed effect model and random effects model.

RESULTS

Three RCTs were included. Showed less risk of therapeutic failure with CPAP compared with HFNC (RR=0.7; 95%CI 0.5-0.99) developed hours later in patients with CPAP (MD=3.16; 95%CI 1.55-4.77). We did not find differences in other outcomes, such as need of invasive ventilation (RR=0.60; 95%CI 0.25-1.43), apnea (RR=0.40; 95%CI 0.08-1.99), or number of days in the intensive care unit (MD=0.02; 95%CI -0.38 to 0.42), and length of hospitalization (MD=-1.00; 95%IC -2.66 to 0.66). Adverse events (skin lesions) were more common with CPAP (RR 2.47; 95%CI 1.17-5.22).

CONCLUSIONS

In moderate/severe bronchiolitis CPAP demonstrated a lower risk of therapeutic failure and a longer time to failure. But more adverse events like nasal injury. There were no differences in other variables.

Comparison of high flow nasal cannula and non-invasive positive pressure ventilation in children with bronchiolitis: A meta-analysis of randomized controlled trials

BACKGROUND

The effects of high-flow nasal cannula (HFNC) compared to non-invasive positive pressure ventilation (NIPPV) on children with bronchiolitis remain unclear.

METHODS

This meta-analysis was performed following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement. Randomized controlled trials (RCTs) were identified from a comprehensive search in PubMed, EMBASE, Cochrane Library, and Web of Science without time and language limitations. Primary endpoints include the rate of treatment failure, the rate of need for intubation, and the pediatric intensive care unit (PICU) length of stay.

RESULTS

Five RCTs including 541 children of less than 24 months were enrolled in the meta-analysis. Compared to the NIPPV group, the rate of treatment failure was significantly higher in the HFNC treatment group (I ² = 0.0%, P = 0.574; RR 1.523, 95% CI 1.205 to 1.924, P < 0.001). No significant difference was noted in the need for intubation (I ² = 0.0%, P = 0.431; RR 0.874, 95% CI 0.598 to 1.276, P = 0.485) and the PICU length of stay (I ² = 0.0%, P = 0.568; WMD = -0.097, 95% CI = -0.480 to 0.285, P = 0.618) between the HFNC group and the NIPPV treatment.

CONCLUSION

Compared to the NIPPV group, HFNC therapy was associated with a significantly higher treatment failure rate in children suffering from bronchiolitis. The intubation rate and the PICU length of stay were comparable between the two approaches.

Clinical practices related to high-flow nasal cannulas in pediatric critical care in Brazil compared to other countries: a Brazilian survey

Objetivo

Descrever as práticas clínicas atuais relacionadas à utilização de cânula nasal de alto fluxo por intensivistas pediátricos brasileiros e compará-las com as de outros países.

Métodos

Para o estudo principal, foi administrado um questionário a intensivistas pediátricos em países das Américas do Norte e do Sul, Ásia, Europa e Austrália/Nova Zelândia. Comparou-se a coorte brasileira com coortes dos Estados Unidos, Canadá, Reino Unido e Índia.

Resultados

Responderam ao questionário 501 médicos, dos quais 127 eram do Brasil. Apenas 63,8% dos participantes brasileiros tinham disponibilidade de cânula nasal de alto fluxo, em contraste com 100% dos participantes no Reino Unido, no Canadá e nos Estados Unidos. Coube ao médico responsável a decisão de iniciar a utilização de uma cânula nasal de alto fluxo segundo responderam 61,2% dos brasileiros, 95,5% dos localizados no Reino Unido, 96,6% dos participantes dos Estados Unidos, 96,8% dos médicos canadenses e 84,7% dos participantes da Índia; 62% dos participantes do Brasil, 96,3% do Reino Unido, 96,6% dos Estados Unidos, 96,8% do Canadá e 84,7% da Índia relataram que o médico responsável era quem definia o desmame ou modificava as regulagens da cânula nasal de alto fluxo. Quando ocorreu falha da cânula nasal de alto fluxo por desconforto respiratório ou insuficiência respiratória, 82% dos participantes do Brasil considerariam uma tentativa com ventilação não invasiva antes da intubação endotraqueal, em comparação com 93% do Reino Unido, 88% dos Estados Unidos, 91,5% do Canadá e 76,8% da Índia. Mais intensivistas brasileiros (6,5%) do que do Reino Unido, Estados Unidos e Índia (1,6% para todos) afirmaram utilizar sedativos com frequência concomitantemente à cânula nasal de alto fluxo.

Conclusão

A disponibilidade de cânulas nasais de alto fluxo no Brasil ainda não é difundida. Há algumas divergências nas práticas clínicas entre intensivistas brasileiros e seus colegas estrangeiros, principalmente nos processos e nas tomadas de decisão relacionados a iniciar e desmamar o tratamento com cânula nasal de alto fluxo.

The starting rate for high-flow nasal cannula oxygen therapy in infants with bronchiolitis: Is clinical judgment enough?

OBJECTIVES

To determine whether in infants with bronchiolitis admitted to a pediatric intensive care unit (PICU) the starting rate for high-flow nasal cannula (HFNC) therapy set by the attending physicians upon clinical judgment meets patients' peak inspiratory flow (PIF) demands and how it influences respiratory mechanics and breathing effort.

METHODOLOGY

We simultaneously obtained respiratory flow and esophageal pressure data from 31 young infants with moderate-to-severe bronchiolitis before and after setting the HFNC rate at 1 L/kg/min (HFNC-1), 2 L/kg/min (HFNC-2) or upon clinical judgment and compared data for PIF, respiratory mechanics, and breathing effort.

RESULTS

Before HFNC oxygen therapy started, 16 (65%) infants had a PIF less than 1 L/kg/min (normal-PIF) and 15 (45%) had a PIF more than or equal to 1 L/kg/min (high-PIF). Normal-PIF-infants had higher airway resistance (p < .001) and breathing effort indexes (e.g., pressure rate product per min [PTP/min], p = .028) than high-PIF-infants. Starting the HFNC rate upon clinical judgment (1.20-2.05 L/kg/min) met all infants' PIFs. In normal-PIF-infants, the clinically judged flow rate increased PIF (p = .081) and tidal volume (p = .029), reduced airway resistance (p = .011), and intrinsic positive end-expiratory pressure (p = .041), whereas, in both high-PIF and normal-PIF infants, it decreased respiratory rate (p < .001) and indexes of breathing effort such as PTP/min (in normal-PIF infants, p = .004; in high-PIF infants, p = .001). The 2 L/kg/min but not 1 L/kg/min rate induced similar effects.

CONCLUSIONS

The wide PIF distribution in our PICU population of infants with bronchiolitis suggests two disease phenotypes whose therapeutic options might differ. An initial flow rate of nearly 2 L/kg/min meets patients' flow demands and improves respiratory mechanics and breathing effort.

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.

The effect of heated humidified nasal high flow oxygen supply on exercise tolerance in patients with interstitial lung disease: A pilot study

BACKGROUND AND OBJECTIVES

Patients with interstitial lung disease (ILD) experience early symptoms of dyspnoea and leg fatigue during exercise together with severe and rapid oxygen desaturation. Heated and humidified nasal high flow oxygen (NHF) has been proven to enhance exercise endurance and physiological parameters in COPD patients. This study aims to evaluate the effect of NHF on exercise tolerance in ILD patients.

METHODS

Twenty-five patients (10 female) with severe ILD performed three constant-load (70% maximal workload) cycling tests to exhaustion under different breathing conditions: room air, oxygen supplementation (4 L min^-1 O₂) and NHF (inspiratory O₂ fraction 0.5, 30-50 L min^-1, heated 34 °C and humidified).

RESULTS

Endurance time was significantly longer with NHF (618 ± 297 s) compared to O₂ (369 ± 217 s, p < 0.001) and room air (171 ± 76 s, p < 0.001). Kinetics of oxygen desaturation, chronotropic response, dyspnoea and leg fatigue sensations were delayed with NHF. At exhaustion with NHF, compared to the two other conditions, oxygen desaturation was less severe while heart rate, dyspnoea and leg fatigue were similar.

CONCLUSION

NHF significantly improved endurance time, physiological parameters and sensations during exercise in severe ILD patients. NHF may be useful to improve functional capacities and facilitate pulmonary rehabilitation in ILD.

Transcutaneous monitoring of diaphragm activity as a measure of work of breathing in preterm infants

OBJECTIVE

Monitoring work of breathing (WOB) is important to assess the pulmonary condition and adjust respiratory support in preterm infants. Conventional WOB measurement (esophageal pressure, tidal volume) is invasive and we hypothesized that monitoring diaphragm activity could be a noninvasive alternative to estimate WOB. The objective was to determine the correlation between conventional WOB measures and diaphragm activity, in preterm infants.

METHODS

WOB and diaphragm activity, measured with transcutaneous electromyography (dEMG), were simultaneously recorded at different nasal continuous positive airway pressure (nCPAP) levels. During a 30-s recording at each nCPAP level, dEMG parameters, inspiratory WOB (WOB_i ), and pressure time product (PTP_in ) were calculated per breath. The correlation coefficient between WOB- and dEMG-measures was calculated using single breaths and after aggregating all breaths into deciles of incremental WOB_i .

RESULTS

Fifteen preterm infants were included (median gestational age, 28 weeks). Single-breath analysis showed a poor median correlation of 0.27 (interquartile range [IQR], 0.03 to 0.33) and 0.08 (IQR, -0.03 to 0.28), respectively, for WOB_i and PTP_in with peak diaphragmatic activity (dEMG_peak ). A modest median correlation coefficient of 0.65 (IQR, 0.13 to 0.79) and 0.43 (IQR, -0.33 to 0.69) was found for, respectively, WOB_i and PTP_in with dEMG_peak in the aggregated analysis.

CONCLUSION

Diaphragm activity showed a modest correlation with WOB_i and PTP_in in an aggregated analysis. This finding warrants further studies in infants with more significant lung disease.

Trends in Bronchiolitis ICU Admissions and Ventilation Practices: 2010-2019

OBJECTIVES

To determine the changes in ICU admissions, ventilatory support, length of stay, and cost for patients with bronchiolitis in the United States.

METHODS

Retrospective cross-sectional study of the Pediatric Health Information Systems database. All patients age <2 years admitted with bronchiolitis and discharged between January 1, 2010 and December 31, 2019, were included. Outcomes included proportions of annual ICU admissions, invasive mechanical ventilation (IMV), noninvasive ventilation (NIV), and cost.

RESULTS

Of 203 859 admissions for bronchiolitis, 39 442 (19.3%) were admitted to an ICU, 6751 (3.3%) received IMV, and 9983 (4.9%) received NIV. ICU admissions for bronchiolitis doubled from 11.7% in 2010 to 24.5% in 2019 (P < .001 for trend), whereas ICU admissions for all children in Pediatric Health Information Systems <2 years of age increased from 16.0% to 21.1% during the same period (P < .001 for trend). Use of NIV increased sevenfold from 1.2% in 2010 to 9.5% in 2019 (P < .001 for trend). Use of IMV did not significantly change (3.3% in 2010 to 2.8% in 2019, P = .414 for trend). In mixed-effects multivariable logistic regression, discharge year was a significant predictor of NIV (odds ratio: 1.24; 95% confidence interval [CI]: 1.23-1.24) and ICU admission (odds ratio: 1.09; 95% CI: 1.09-1.09) but not IMV (odds ratio: 1.00; 95% CI: 1.00-1.00).

CONCLUSIONS

The proportions of children with bronchiolitis admitted to an ICU and receiving NIV have substantially increased, whereas the proportion receiving IMV is unchanged over the past decade. Further study is needed to better understand the factors underlying these temporal patterns.

Assessment of Peak Inspiratory Flow in Young Infants with Acute Viral Bronchiolitis: Physiological Basis for Initial Flow Setting in Patients Supported with High-Flow Nasal Cannula

OBJECTIVE

To assess the inspiratory demand in young infants with acute viral bronchiolitis to provide a physiological basis for initial flow setting for patients supported with high flow nasal cannula.

STUDY DESIGN

Prospective study in 44 infants up to 6 months old with acute viral bronchiolitis, admitted to a pediatric intensive care unit from November 2017 to March 2019. Airflow measurements were performed using spirometry. The primary endpoint was the inspiratory demand as measured by peak tidal inspiratory flow (PTIF). The secondary endpoints were the relationships determined between PTIF, patient weight, and disease severity.

RESULTS

Median (Q₂₅-Q₇₅) age and weight of the patients were 37 (20-67) days and 4.3 (3.5-5.0) kg, respectively. Mean PTIF was 7.45 (95% CI 6.51-8.39, min-max: 2.40-16.00) L/minute. PTIF indexed to weight was 1.68 (95% CI 1.51-1.85, min-max: 0.67-3.00) L/kg/minute. PTIF was <2.5 L/kg/minute in 89% (95% CI 75-96) of infants. PTIF was correlated with weight (ρ= 0 .55, P < .001) but not with markers of disease severity, including modified Woods clinical asthma score, Silverman-Andersen score, respiratory rate, fraction of inspired oxygen, and PCO₂.

CONCLUSIONS

High flow nasal cannula therapy is used commonly to support infants with acute viral bronchiolitis. The efficiency of the device is optimal if the flow setting matches the patient's inspiratory demand. According to our results, a flow rate of <2.5 L/kg/minute would be appropriate in most situations.

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 Nasal Cannula in Bronchiolitis at a Pediatric Emergency Department: Trends and Outcomes

OBJECTIVES

Use of high-flow nasal cannula (HFNC) for bronchiolitis has increased, but data describing the current use and impact of this therapy are limited. Our objective with this study was to describe the use of HFNC for bronchiolitis in a pediatric emergency department (ED) from 2013 to 2019 and to explore associations with clinical outcomes.

METHODS

This was a retrospective cohort study of children aged 2 to 24 months with the diagnosis of bronchiolitis. The primary outcome was HFNC initiation in the ED. Secondary outcomes included admission rate, ICU (PICU) admission, transfer to PICU from floor, and endotracheal intubation. An adjusted interrupted times series analysis was performed to analyze changes in rates of primary and secondary outcomes over time.

RESULTS

In total 11 149 children met inclusion criteria; 902 (8.1%) were initiated on HFNC. The rate of HFNC initiation increased from 1.3% in 2012-2013 to 17.0% in 2018-2019 (P _trend ≤ .001). Less than 30% of children initiated on HFNC were hypoxic. There were no significant changes over time in rates of hospital admission, PICU admission, or PICU transfer, adjusting for clinical severity, seasonality, and provider variation. Intubation rate increased over the study period.

CONCLUSIONS

We found a 13-fold increase in HFNC use over a 6-year period with no evidence of improvement in clinically meaningful outcomes. Clinical benefit should be clearly defined before further expansion of the use of HFNC for bronchiolitis in the ED.

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.

Outcomes of High-Flow Nasal Cannula Vs. Nasal Continuous Positive Airway Pressure in Young Children With Respiratory Distress: A Systematic Review and Meta-Analysis

Background: Continuous positive airway pressure (CPAP) has been associated with a lower risk of treatment failure than high-flow nasal cannula (HFNC) in pediatric patients with respiratory distress and severe hypoxemia. However, the publication of new trials on children younger than 2 years warrants a review and updated meta-analysis of the evidence. Methods: We conducted a systematic search in the PubMed, Scopus, and Google scholar databases for randomized controlled trials (RCTs) in pediatric patients with acute respiratory distress that examined outcomes of interest by the two usual management modalities (CPAP and HFNC). We used pooled adjusted relative risks (RRs) to present the strength of association for categorical outcomes and weighted mean differences (WMDs) for continuous outcomes. Results: We included data from six articles in the meta-analysis. The quality of the studies was deemed good. Included studies had infants with either acute viral bronchiolitis or pneumonia. Compared to CPAP, HFNC treatment carried a significantly higher risk of treatment failure [RR, 1.45; 95% CI, 1.06 to 1.99; I ² = 0.0%, n = 6]. Patients receiving HFNC had a lower risk of adverse events, mainly nasal trauma [RR, 0.30; 95% CI, 0.14 to 0.62; I ² = 0.0%, n = 2] than the others. The risk of mortality [RR, 3.33; 95% CI, 0.95, 11.67; n = 1] and need for intubation [RR, 1.69; 95% CI, 0.97, 2.94; I ² = 0.0%, n = 5] were statistically similar between the two management strategies; however, the direction of the pooled effect sizes is indicative of a nearly three times higher mortality and two times higher risk of intubation in those receiving HFNC. We found no statistically significant differences between the two management modalities in terms of modified woods clinical asthma score (M-WCAS; denoting severity of respiratory distress) and hospitalization length (days). Patients receiving HFNC had the time to treatment failure reduced by approximately 3 h [WMD, -3.35; 95% CI, -4.93 to -1.76; I ² = 0.0%, n = 2] compared to those on CPAP. Conclusions: Among children with respiratory distress younger than 2 years, HFNC appears to be associated with higher risk of treatment failure and possibly, an increased risk of need for intubation and mortality. Adequately powered trials are needed to confirm which management strategy is better.

High-Flow Nasal Cannula Therapy in Children With Acute Respiratory Distress With Hypoxia in A Pediatric Intensive Care UnitA Single Center Experience

Aim: High-flow nasal cannulas (HFNCs) show potential in the application of positive pressure, improving gas exchange, and decreasing work of breathing in patients with acute respiratory distress. The aims of this study were to elucidate the indications for HFNC therapy in children of all ages and diagnoses, and to evaluate the efficacy and risk factors for failure of HFNC therapy in children with acute respiratory distress with hypoxia in a pediatric intensive care unit. Methods: We conducted this retrospective cohort study at a tertiary pediatric intensive care unit between January 1, 2018 and December 31, 2020. All children, from 1 month to 18 years of age, with acute respiratory distress with hypoxia and HFNC therapy were eligible. The clinical data were reviewed. Results: One hundred and two children met the eligibility criteria for the study, of whom 57 (55.9%) were male, and the mean age was 7.00 6.79 years. Seventy-eight (76.5%) of the children had underlying disorders. The most common indications for the use of HFNC therapy were pneumonia (40, 39.2%), sepsis-related respiratory distress (17, 16.7%), and bronchiolitis (16, 15.7%). The failure rate was 15.7% (16 of 102 children). Higher initial and maximum fraction of inspiration O2 levels and lower initial and lowest SpO2/FiO2 (S/F) ratio were early and possible signs of failure requiring escalation of respiratory support. Conclusion: In our population, we found that HFNC therapy could be initiated as the first-line therapy for various etiologies of acute respiratory distress with hypoxia in a pediatric intensive care unit and for all age groups.

Has the introduction of high-flow nasal cannula modified the clinical characteristics and outcomes of infants with bronchiolitis admitted to pediatric intensive care units? A retrospective study

BACKGROUND

This study aimed to assess how the emergence of high-flow nasal cannula (HFNC) has modified the demographic and clinical characteristics as well as outcomes of infants with bronchiolitis admitted to a pediatric intensive care unit (PICU).

METHODS

This was a single-center retrospective study including infants aged 1 day to 6 months with bronchiolitis requiring HFNC, noninvasive ventilation (NIV), or invasive ventilation on admission.

RESULTS

A total of 252 infants (mean age 53±36 days) were included in the study. The use of HFNC increased from 18 (21.4%) during 2013-2014 to 53 infants (55.2%) during 2015-2016. The length of stay in the PICU decreased over time from 4.7±2.9 to 3.5±2.7 days (P<0.01) but the hospital length of stay remained similar (P=0.17). On admission, patients supported by HFNC as the first-line therapy were older. The PICU length of stay was similar according to the type of respiratory support (P=0.16), but the hospital length of stay was longer for patients supported by HFNC (P=0.01).

CONCLUSION

The distribution of respiratory support has significantly changed over time for patients with bronchiolitis and HFNC is increasingly used. The demographic and clinical characteristics of the have not changed over time. However, the PICU length of stay decreased significantly.

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.

The Influence of High Flow Nasal Cannulae on the Outcomes of Severe Respiratory Disease in Children Admitted to a Regional Hospital in South Africa

In settings where access to paediatric intensive care unit (PICU) facilities is constrained and transfer capacity is limited, High Flow Nasal Cannulae (HFNC) might fill an important service gap. The aim of this study was to document the effect of HFNC on the outcomes of children admitted with severe respiratory disease at a regional hospital without a PICU in Cape Town, South Africa. It is a 4-year retrospective analysis documenting two periods of 2 years each, one before (2013-15) and one after (2016-18) the initiation of HFNC use. Patients were between the ages of 2 months and 13 years and had been admitted to a paediatric ward. Outcomes were defined by the need for transfer to a tertiary hospital, the need for invasive ventilation and death. There were 90 instances of HFNC use with a significant reduction in the number of children who were transferred (59 vs. 31), invasively ventilated (20 vs. 6, p ≤ 0.01) and who died (3 vs. 0, p = 0.02). Before HFNC implementation, there was also a significantly greater proportion of transferred children who remained on low flow nasal cannulae (15 vs. 2, p ≤ 0.001) at the tertiary hospital. Children who failed HFNC use tended to do this within a day of initiation (Median 11 vs. 60 h for success, p ≤ 0.001). There were no complications related to its use. We believe that in our setting the utilization of HFNC has helped to timeously and accurately identify children needing to be transferred and may mitigate against severe respiratory disease progression.

The influence of flowrate and gas density on positive airway pressure for high flow nasal cannula applied to infant airway replicas

High flow nasal cannula (HFNC) therapy has been previously shown to produce positive upper airway pressures in adult and child patients. This work aimed to evaluate and quantify the effects of HFNC flowrate and gas type on airway pressures measured in vitro in infant airway replicas. Ten realistic infant airway replicas, extending from nares to trachea, were connected in turn to a lung simulator and were supplied gas flows through HFNC. Air and heliox were each provided at two weight-indexed flowrates, 1 l/min/kg and 2 l/min/kg. Pressure and lung volume were continuously measured during simulated breathing. For constant simulated patient effort, no statistically significant change in tidal volume was measured between baseline and lower or higher HFNC flowrates, nor was there any significant difference in tidal volume between air and heliox. Tracheal pressure increased with increasing HFNC flow rate, and was highly variable between airway replicas. Higher pressures were measured for air versus heliox. For air supplied at 2 l/min/kg, average airway pressures in excess of 4 cm H₂O were generated, with positive end-expiratory pressure (PEEP) ranging from 2.5 to nearly 12 cm H₂O across the replicas. A predictive correlation for PEEP was proposed based on supplied gas density and flow velocities exiting the cannula and nares, and was able to account for a portion of variability between airway replicas (R² = 0.913). Additionally, PEEP was well correlated with, and predictive of, expiratory peak pressure (R² = 0.939) and average inspiratory pressure (R² = 0.944).

Continuous Positive Airway Pressure vs. High Flow Nasal Cannula in children with acute severe or moderate bronchiolitis. A systematic review and Meta-analysis

OBJECTIVE

To compare the safety and effectiveness of Continuous Positive Airway Pressure (CPAP) vs. High Flow Nasal Cannula (HFNC) to prevent therapeutic failure and the need of invasive ventilation in children with acute moderate-severe bronchiolitis.

DESIGN

A systematic review and meta-analysis.

SETTING

Medline, Embase, Lilacs, Cochrane and gray literature (May 2020) was performed.

PARTICIPANTS

Randomized clinical trials patients with moderate to severe bronchiolitis.

MAIN VARIABLES

Therapeutic failure, need for invasive ventilation, adverse events, length of PCCU and of hospital stay.

INTERVENTION

The quality of the studies was assessed with the Cochrane risk and bias tool. We conducted meta-analysis using fixed effect model and random effects model.

RESULTS

Three RCTs were included. Showed less risk of therapeutic failure with CPAP compared with HFNC (RR=0.7; 95%CI 0.5-0.99) developed hours later in patients with CPAP (MD=3.16; 95%CI 1.55-4.77). We did not find differences in other outcomes, such as need of invasive ventilation (RR=0.60; 95%CI 0.25-1.43), apnea (RR=0.40; 95%CI 0.08-1.99), or number of days in the intensive care unit (MD=0.02; 95%CI -0.38 to 0.42), and length of hospitalization (MD=-1.00; 95%IC -2.66 to 0.66). Adverse events (skin lesions) were more common with CPAP (RR 2.47; 95%CI 1.17-5.22).

CONCLUSIONS

In moderate/severe bronchiolitis CPAP demonstrated a lower risk of therapeutic failure and a longer time to failure. But more adverse events like nasal injury. There were no differences in other variables.

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.

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.

Variation in Practice Related to the Use of High Flow Nasal Cannula in Critically Ill Children

OBJECTIVES

To determine current management of critically ill children and gather views regarding high flow nasal cannula therapy and to evaluate research priorities for a large prospective randomized controlled trial of noninvasive respiratory support in children.

DESIGN

Multinational cross-sectional questionnaire survey conducted in 2018.

SETTING

The sample included pediatric intensive care physicians in North and South America, Asia, Europe, and Australia/New Zealand.

MEASUREMENT

Questions consisted of: 1) characteristics of intensivists and hospital, 2) practice of high flow nasal cannula, 3) supportive treatment, and 4) research of high flow nasal cannula.

INTERVENTIONS

None.

MAIN RESULTS

We collected data from 1,031 respondents; 919 (North America, 215; Australia/New Zealand, 34; Asia, 203; South America, 186; Europe, 281) were analyzed. Sixty-nine percent of the respondents used high flow nasal cannula in non-PICU settings in their institutions. For a case of bronchiolitis/pneumonia infant, 2 L/kg/min of initial flow rate was the most commonly used. For a scenario of pneumonia with 30 kg weight, more than 60% of the respondents initiated flow based on patient body weight; while, 18% applied a fixed flow rate. Noninvasive ventilation was considered as a next step in more than 85% of respondents when the patient is failing with high flow nasal cannula. Significant practice variations were observed in clinical practice markers used, flow weaning strategy, and supportive practices. Views comparing high flow nasal cannula to continuous positive airway pressure also noticeably varied across the respondents.

CONCLUSIONS

Significant practice variations including views of high flow nasal cannula compared to continuous positive airway pressure was found among pediatric intensive care physicians. To expedite establishment and standardization of high flow nasal cannula practice, research aimed at understanding the heterogeneity found in this study should be undertaken.