High-flow Nasal Cannula Therapy Research Articles

Characterization of SARS-CoV-2 Aerosols Dispersed During Noninvasive Respiratory Support of Patients With COVID-19.

In the midst of the COVID-19 pandemic, noninvasive respiratory support (NRS) therapies such as high-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) were central to respiratory care. The extent to which these treatments increase the generation and dispersion of infectious respiratory aerosols is not fully understood. The objective of this study was to characterize SARS-CoV-2 aerosol dispersion from subjects with COVID-19 undergoing NRS therapy. Several different aerosol sampling devices were used to collect air samples in the vicinity of 31 subjects with COVID-19, most of whom were receiving NRS therapy, primarily HFNC. Aerosols were collected onto filters and analyzed for the presence of SARS-CoV-2 RNA. Additional measurements were collected in an aerosol chamber with healthy adult subjects using respiratory therapy devices under controlled and reproducible conditions. Fifty aerosol samples were collected from subjects receiving HFNC or NIV therapy, whereas 6 samples were collected from subjects not receiving NRS. Only 4 of the 56 aerosol samples were positive for SARS-CoV-2 RNA, and all positive samples were collected using a high air flow scavenger mask collection device placed in close proximity to the subject. The chamber measurements with healthy subjects did not show any significant increase in aerosol dispersion caused by the respiratory therapy devices compared to baseline. Our findings demonstrate very limited detection of SARS-CoV-2-containing aerosols in the vicinity of subjects with COVID-19 receiving NRS therapies in the clinical setting. These results, combined with controlled chamber measurements showing that HFNC and NIV device usage was not associated with increased aerosol dispersion, suggest that NRS therapies do not result in increased dispersal of aerosols in the clinical setting.

Factors associated with unsuccessful high-flow nasal cannula therapy in patients presenting to the emergency department for acute hypoxemic respiratory failure

Factors associated with unsuccessful high-flow nasal cannula therapy in patients presenting to the emergency department for acute hypoxemic respiratory failure

Noninvasive Respiratory Support Effects on Sighs in Preterm Infants by Electrical Impedance Tomography.

To evaluate differences regarding sigh frequency between noninvasive respiratory support types and to assess regional ventilation distribution, delta Z, and end-expiratory lung impedance differences before and after sighs. Very low-birth-weight infants with gestational ages less than 32 wk were included in the study. Participants were split into two groups: those receiving continuous positive airway pressure and infants receiving high-flow nasal cannula therapy. The study enrolled 30 infants. The high-flow nasal cannula therapy group had more sighs per 10-min period than infants receiving continuous positive airway pressure (p = 0.016). Ventilation distribution was similar in the anterior and right ventilation distribution compartments pre- and post-sigh (46.30% vs. 45.68% and 54.27% vs. 55.26%, respectively). No statistically significant increase in end-expiratory lung impedance or delta Z was observed in global or separate lung regions (p > 0.05). The study has demonstrated that sighs are more frequent in infants receiving high-flow nasal cannula respiratory support compared to continuous positive airway pressure. Spontaneously occurring sighs on noninvasive respiratory support due to respiratory distress syndrome (RDS) do not increase end-expiratory lung impedance or alter delta Z, and appear to have limited clinical significance. Prospectively registered at www. gov , reg. No. NCT04542096, reg. date 01/09/2020.

1111: PREDICTORS OF HIGH-FLOW NASAL CANNULA FAILURE IN COVID-19

Introduction: Severe coronavirus disease-19 (COVID-19) is characterized by progressive hypoxemia and patients may require advanced oxygen therapy, including high-flow nasal cannula (HFNC) therapy and mechanical ventilation. Previous data has suggested that the ROX index, IL-6 levels, thrombocytopenia, and kidney injury may predict failure of high-flow nasal cannula therapy. Our study aims to evaluate risk factors that predict HFNC failure in our patient population. Methods: Retrospective cohort study of patients treated for COVID-19 across 4 hospitals in Atlanta, Georgia between February 2020 and February 2021. Patients placed on high-flow nasal cannula within the first 24 hours of admission and who remained on high-flow nasal cannula for at least 6 consecutive hours were identified. Patients that met our cohort criteria were followed for the first seven days of admission and transition across oxygen therapy modalities were examined. Demographic and comorbidity data of patients who failed high-flow nasal cannula therapy within the first 7 days, defined as need for mechanical ventilation or death, were compared to patients who did not fail. Results: There were 1205 patients placed on high-flow nasal cannula oxygen therapy in our hospitals between February 2020 and February 2021. In total, 465 patients met inclusion criteria. Of the cohort, 35.9% remained on high-flow, 32.0 % transitioned to low-flow or room air, and 31.6% failed high-flow nasal cannula therapy within the first week of hospitalization (26.2% failed due to requiring intubation and 5.4% failed due to death). When comparing demographics and comorbidities, patients who failed were older (median age 67.5 vs 62 years, p=0.01) and more frequently had renal disease (28.8% vs 18.5%, p=0.02). There were no significant differences in sex, race, congestive heart failure, pulmonary disease, hypertension, diabetes mellitus, liver disease, or metastatic cancer. Conclusions: In our patient population, 31.6% of patients failed high-flow nasal cannula therapy within the first week of admission due to mechanical ventilation or death. Age and renal disease were significant risk factors for high-flow nasal cannula therapy failure in COVID-19 patients.

Predictors of Intensive Care Admission in Hypoxemic Bronchiolitis Infants, Secondary Analysis of a Randomized Trial

To evaluate in a preplanned secondary analysis of our parent randomized controlled trial predictors of intensive care unit (ICU) admission in infants with bronchiolitis and analyze if these predictors are equally robust for children receiving high-flow or standard-oxygen. A secondary analysis of a multicenter, randomized trial of infants aged <12months with bronchiolitis and an oxygen requirement was performed using admission and outcome data of all 1472 enrolled infants. The primary outcome was ICU admission. The predictors evaluated were baseline characteristics including physiological data and medical history. Of the 1472 enrolled infants, 146 were admitted to intensive care. Multivariate predictors of ICU admission were age (weeks) (OR: 0.98 [95% CI: 0.96-0.99]), pre-enrolment heart rate >160/min (OR: 1.80 [95% CI: 1.23-2.63]), pre-enrolment SpO2 (transcutaneous oxygen saturation) (%) (OR: 0.91 [95% CI: 0.86-0.95]), previous ICU admission (OR: 2.16 [95% CI: 1.07-4.40]), and time of onset of illness to hospital presentation (OR: 0.78 [95% CI: 0.65-0.94]). The predictors were equally robust for infants on high-flow nasal cannula therapy or standard-oxygen therapy. Age <2months, pre-enrolment heart rate >160/min, pre-enrolment SpO2 of <87%, previous ICU admission and time of onset of ≤2days to presentation are predictive of an ICU admission during the current hospital admission of infants with bronchiolitis independent of oxygenation method used. ACTRN12613000388718.

High-Flow Nasal Cannula Therapy for Respiratory Support in Adult Intensive Care Unit Patients

What is the effectiveness of high-flow nasal cannula (HFNC) therapy compared with standard oxygen therapy, noninvasive ventilation, or noninvasive positive pressure (NIPPV) ventilation for respiratory support in adults in the intensive care unit?Critically ill patients are at high risk for severe hypoxemia that can lead to significant tissue damage and death if not corrected. Supplemental oxygen can be delivered via multiple methods, including mechanical ventilation, noninvasive ventilation, NIPPV, HFNC therapy, and low-flow nasal cannula (LFNC) therapy.1 Up to 40% of all patients admitted to the intensive care unit (ICU) receive mechanical ventilation; although this method is often necessary, it presents risks and potential complications, including trauma to the pulmonary system and increased mortality.2,3To avoid these complications, the use of alternative methods of respiratory support that can provide adequate oxygen levels is often considered. Use of LFNC therapy can be helpful but often cannot provide a sufficiently high level of oxygen for critically ill patients. However, HFNC therapy can provide high levels of oxygen, and its use in the ICU has been growing in recent years.4High-flow nasal cannula therapy delivers heated and humidified oxygen via the nose at high flow rates of up to 60 L/min. The high flow rates produce low levels of positive pressure in the upper airways, which can clear out expired carbon dioxide, leading to reduced work of breathing and decreased respiratory rate.5 Noninvasive positive pressure ventilation, which refers primarily to continuous positive airway pressure or bilevel positive airway pressure ventilation, can be used when patients require high levels of supplemental oxygen and need some level of mechanical support. The oxygen is delivered via a tight-fitting mask, typically over the nose, mouth, or both; this mask can be uncomfortable and make it difficult to maintain adequate positioning.6The purpose of this review was to compare the efficacy and safety of HFNC therapy with those of the other common noninvasive respiratory support methods in the ICU setting.This summary was based on an update to a previously published systematic review conducted in 2017.7 As new evidence on a topic becomes available, updates are necessary to account for the results that the new evidence presents. This update, conducted by Lewis et al,8 included 31 randomized controlled trials comprising 5136 adult participants. The authors of this review investigated several outcomes, with the primary ones being treatment failure (need to escalate to invasive ventilation), in-hospital mortality, and adverse events (pneumonia).The authors independently assessed the risk of bias for each study, including selection, performance, detection, attrition, reporting, and publication biases. They resolved any disagreements by reviewing the data together and through discussion.Lewis et al8 used risk ratios (RRs) with 95% CIs for dichotomous outcomes as measures of treatment effect between various comparisons and outcomes. They used the internationally approved Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to determine the certainty of evidence—high, moderate, low, or very low—for each outcome9: This review showed that, overall, there was little or no difference in the evidence when comparing HFNC use with standard oxygen therapy or NIPPV in the outcomes explored. There was low-certainty evidence showing that HFNC therapy may lead to less treatment failure compared with standard oxygen therapy, with the classification of low certainty based on heterogeneity (differences in how the studies were conducted) and an unclear risk of bias in the studies.Currently, more than 50 studies are being conducted on the use of HFNC therapy; this high level of research activity is likely related to the increase in the use of HFNC therapy resulting from the COVID-19 pandemic. Upon publication, these studies can be added to the evaluation to provide additional guidance.The evidence from this systematic review can affect the decisions of clinical care teams when they are creating treatment plans for critically ill patients. Advocating for the best evidence-based treatment remains an important part of the role of critical care nurses. We must always consider the best available evidence and understand the feasibility, appropriateness, meaningfulness, and effectiveness of any intervention to determine whether it is suitable to implement in our individual context.

Editor's Choice Articles for December.

Editor's Choice Articles for December.

In Vitro Evaluation of Nebulized Pharmaceutical Aerosol Delivery to the Lungs Using a New Heated Dryer System (HDS).

The objective of this study was to develop a new heated dryer system (HDS) for high efficiency lung delivery of nebulized aerosol and demonstrate performance with realistic in vitro testing for trans-nasal aerosol administration simultaneously with high-flow nasal cannula (HFNC) therapy and separately for direct oral inhalation (OI) of the aerosol. With the HDS-HFNC and HDS-OI platforms, new active synchronization control routines were developed to sense subject inhalation and coordinate drug aerosol delivery. In vitro experiments were conducted to predict regional drug loss and lung delivery efficiency in systems that included the HDS with various patient interfaces, realistic airway models, and simulated breathing waveforms. For the HDS-HFNC platform and a repeating breathing waveform, total system loss was < 10%, extrathoracic deposition was approximately 6%, and best-case lung delivery efficiency was 75-78% of nebulized dose. Inclusion of randomized breathing with the HFNC system decreased lung delivery efficiency by ~ 10% and had no impact on nasal depositional loss. For the HDS-OI platform and best-case mouthpiece, total system loss was < 8%, extrathoracic deposition was < 1%, and lung delivery efficiency was > 90% of nebulized dose. Normal vs. deep randomized oral inhalation had little impact on performance of the HDS-OI platform and environmental aerosol loss was negligible. In conclusion, both platforms demonstrated the potential for high efficiency lung delivery of the aerosol with the HDS-OI platform having the added advantages of nearly eliminating extrathoracic deposition, being insensitive to breathing waveform, and preventing environmental aerosol loss.

Diaphragmatic Ultrasound Predictors of High-Flow Nasal Cannula Therapeutic Failure in Critically Ill Patients With SARS-CoV-2 Pneumonia.

High flow nasal cannula (HFNC) is frequently used in patients with acute respiratory failure, but there is limited evidence regarding predictors of therapeutic failure. The objective of this study was to assess diaphragmatic ultrasound criteria as predictors of failure to HFNC, defined as the need for orotracheal intubation or death. Prospective cohort study including adult patients consecutively admitted to the critical care unit, from July 24 to October 20, 2020, with respiratory failure secondary to SARS-CoV-2 pneumonia who required HFNC. After 12hours of HFNC initiation we measured ROX index (ratio of SpO2 /FiO2 to respiratory rate), excursion and diaphragmatic contraction speed (diaphragmatic excursion/inspiratory time) by ultrasound, both in supine and prone position. In total, 41 patients were analyzed, 25 succeeded and 16 failed HFNC therapy. At 12hours, patients who succeeded HFNC therapy presented higher ROX index in supine position (9.8 [9.1-15.6] versus 5.4 [3.9-6.8], P < .01), and higher PaO2 /FiO2 ratio (186 [135-236] versus 117 [103-162] mmHg, P=.03). To predict therapeutic failure, the supine diaphragmatic contraction speed presented sensitivity of 89% and a specificity of 57%, while the ROX index presented a sensitivity of 92.8% and a specificity of 75%. Diaphragmatic contraction speed by ultrasound emerges as a diagnostic complement to clinical tools to predict HFNC success. Future studies should confirm these results.

Underrepresentation of Respiratory Therapists as Experts in Delphi Studies on Respiratory Practices and Research Priorities.

Delphi survey techniques are a common consensus method used to collect feedback from an expert panel to inform practices, establish guidelines, and identify research priorities. Collecting respiratory therapists' (RT) expertise and experiences as part of consensus-building methodologies is one way to ensure that they align with RT practices and to better influence respiratory care practice. This narrative review aimed to report the RT representation in expert panels of Delphi studies focused on respiratory therapy practices and research priorities. The research question that guided this review is: to what extent are RTs included as expert participants among published Delphi studies relate to respiratory therapy and research topics? We conducted a structured search of the literature and identified 23 papers that reported Delphi studies related to respiratory care practices and 15 that reported on respiratory-related research priorities. Delphi studies that focused on reporting consensus on respiratory care practices included the following: (1) mechanical ventilation, (2) high-flow nasal cannula therapy, (3) COVID-19 respiratory management, (4) home oxygen therapy, (5) cardiopulmonary monitoring, and (6) disease-specific guidelines. Delphi studies that focused on establishing respiratory research priorities included the following: (1) theory and practice-orientated knowledge gaps, and (2) priority research topics for empirical investigation. The results of this review suggest that RTs were rarely included as expert participants and, when involved, were minimally represented (5% to 33%). Given RTs' diverse and relevant experience in respiratory care, incorporating their perspectives to inform future education, respiratory care practices, and research priorities would allow evidence to better align with knowledge gaps deemed important for the respiratory therapy profession.

The ROX index: "Propelled" by high-flow nasal cannula therapy during the COVID-19 pandemic into greater applicability in respiratory support.

The ROX index: "Propelled" by high-flow nasal cannula therapy during the COVID-19 pandemic into greater applicability in respiratory support.

Effect of high-flow nasal cannula therapy on thirst sensation and dry mouth after extubation: A single-centre prospective cohort study

ObjectivesLittle is known regarding the association between the type of oxygen therapy and thirst sensation after extubation. This study aimed to assess the effect of post-extubation high-flow nasal cannula on thirst. Research methodology/design and settingThis single-centre prospective cohort study included 100 ventilated patients. After extubation, patients received either high-flow nasal cannula (n = 19) or conventional oxygen therapy (n = 81). Thirst intensity was evaluated by a self-reporting numeric rating scale, and dry mouth was defined objectively using an oral moisture checking device. Main outcome measuresThe primary outcome was thirst intensity 24 hours post-extubation. Secondary outcomes were thirst intensity at 4 hours post-extubation and prevalence of dry mouth at 4 hours and 24 hours post-extubation. ResultsAt 24 hours post-extubation, the median (interquartile range) thirst intensity was 5 (1, 7) in the high-flow nasal cannula group and 5 (4, 6) in the conventional oxygen group. After adjustment, high-flow nasal cannula therapy was significantly associated with lower thirst intensity (adjusted odds ratio, 0.14; 95 % confidence interval (CI) 0.04–0.49; P = 0.002). At 4 hours post-extubation, high-flow nasal cannula was also associated with lower thirst intensity (adjusted odds ratio, 0.19; 95 % CI, 0.06–0.60; P = 0.005). The number of patients with dry mouth was not significantly different between the two groups (high-flow vs conventional oxygen therapy, 42.1 % vs 30.9 % [4 hours after extubation]; 47.4 % vs 34.6 % [24 hours after extubation]). ConclusionsHigh-flow nasal cannula therapy was associated with lower thirst intensity than conventional oxygen therapy following extubation. However, there was no significant difference in the prevalence of dry mouth.

Commentary on the First-Line Support for Assistance in Breathing in Children Trials on Noninvasive Respiratory Support: Taking a Closer Look.

Noninvasive respiratory support modalities such as high-flow nasal cannula (HFNC) therapy and continuous positive airway pressure (CPAP) are used frequently in pediatric critical care to support acutely ill children with respiratory failure (step-up management) and children following extubation (step-down management). Although there are several observational studies and database analyses comparing the efficacy of HFNC and CPAP, and a few small randomized clinical trials (RCTs), until recently, there were no large RCTs comparing the two modalities in a mixed group of critically ill children. In the first half of 2022, results from the First-Line Support for Assistance in Breathing in Children (FIRST-ABC) trials were published; these comprised a master protocol of two trials: one in acutely ill children (step-up RCT) and one in extubated children (step-down RCT). Each of these pragmatic trials randomized 600 children to either HFNC or CPAP when the treating clinician decided that noninvasive respiratory support beyond standard oxygen therapy was required. The primary outcome was time to liberation from all forms of respiratory support (invasive and noninvasive), excluding supplemental oxygen. The FIRST-ABC trials represent a significant advance in the field of noninvasive respiratory support, which has traditionally been evidence-poor and associated with considerable variability in clinical practice. In this article, we provide an overview of how the FIRST-ABC trials were conceived and conducted, our view on the results, and how the trial findings have changed our clinical practice.

Anesthetic management using high-flow nasal cannula therapy during cardiac catheter examination of a neonate with hypoplastic left heart syndrome

BackgroundSedation during cardiac catheter examination in neonates with complex congenital heart disease is challenging, as even the slightest change in the circulatory or respiratory status can lead to hemodynamic collapse. Here, we report a case wherein we achieved adequate sedation with a high-flow nasal cannula (HFNC) for catheter examination in a neonate with a congenital cardiac anomaly.Case presentationAn 11-day-old boy with hypoplastic left heart syndrome was scheduled for a cardiac catheter examination prior to the Norwood procedure. He underwent bilateral pulmonary artery banding (PAB) on day 1 and was receiving dobutamine, milrinone, alprostadil, and dexmedetomidine in addition to air and nitrogen insufflation via HFNC, which was applied following extubation on day 3 and nitrogen therapy on day 6 owing to persistent pulmonary overcirculation symptoms (tachypnea and low arterial blood pressure) despite bilateral PAB. A catheter examination was performed on day 11 with careful monitoring of expired carbon dioxide and observation of chest wall motion. Adequate sedation was provided with supplemental midazolam and fentanyl along with HFNC without tracheal intubation.ConclusionsThe findings from this case suggest that HFNC is a safe and effective tool for oxygenation during cardiac catheter examination under sedation in neonates.

The optimal management of the patient with COVID-19 pneumonia: HFNC, NIV/CPAP or mechanical ventilation?

The recent pandemic has seen unprecedented demand for respiratory support of patients with COVID-19 pneumonia, stretching services and clinicians. Yet despite the global numbers of patients treated, guidance is not clear on the correct choice of modality or the timing of escalation of therapy for an individual patient. This narrative review assesses the available literature on the best use of different modalities of respiratory support for an individual patient, and discusses benefits and risks of each, coupled with practical advice to improve outcomes. On current data, in an ideal context, it appears that as disease severity worsens, conventional oxygen therapy is not sufficient alone. In more severe disease, i.e. PaO2/FiO2 ratios below approximately 200, helmet-CPAP (continuous positive airway pressure) (although not widely available) may be superior to high-flow nasal cannula (HFNC) therapy or facemask non-invasive ventilation (NIV)/CPAP, and that facemask NIV/CPAP may be superior to HFNC, but with noted important complications, including risk of pneumothoraces. In an ideal context, invasive mechanical ventilation should not be delayed where indicated and available. Vitally, the choice of respiratory support should not be prescriptive but contextualised to each setting, as supply and demand of resources vary markedly between institutions. Over time, institutions should develop clear policies to guide clinicians before demand exceeds supply, and should frequently review best practice as evidence matures.

IMPACT OF HIGH-FLOW NASAL CANNULA THERAPY ON SWALLOWING: A PROSPECTIVE COHORT STUDY

IMPACT OF HIGH-FLOW NASAL CANNULA THERAPY ON SWALLOWING: A PROSPECTIVE COHORT STUDY

The impact of an autonomous nurse-led high-flow nasal cannula oxygen protocol on clinical outcomes of infants with bronchiolitis.

To investigate the relationship of the implementation of a nurse-led high-flow nasal cannula oxygen protocol on the clinical outcomes of infants with bronchiolitis in a regional paediatric unit. Bronchiolitis is a common lower respiratory illness and is the leading cause for hospitalisation of infants globally. Standard care involves the provision of supportive measures. Historically, supplemental oxygen was provided by low-flow nasal cannula. High-flow nasal cannula oxygen has been increasingly adopted despite limited evidence of its efficacy. This study employed non-equivalent, post-implementation only design to explore clinical outcomes of infants with bronchiolitis admitted for high-flow nasal cannula oxygen therapy. The study compared infants in the 24 months before and after the initiation of a high-flow nasal cannula protocol. The primary clinical outcome was length of stay, secondary outcomes included time on high flow, weaning time, escalation of care and time outside of physiological parameters. Implementation strategy evaluation was measured by compliance with applying the protocol, reported as episodes of variance, and duration of variance. The StaRI checklist was selected as the most appropriate reporting guideline. A total of 80 patients were admitted with bronchiolitis and received high-flow nasal cannula oxygen therapy during a 48-month period; 37 patients were prior, and 43 after, the introduction of a nurse-led high-flow nasal cannula protocol. Length of stay was significantly reduced in the post-implementation group compared to the historical control group (83.8 vs. 61.3 h). Time on high flow and weaning time was decreased in the post-implementation group compared to the control group (33.5 vs. 26.7 h and 26 vs.12.25 h, respectively); however, these did not reach statistical significance. There was varied application of the HFNC protocol. The implementation of a nurse-led high-flow nasal cannula protocol was associated with a reduced length of stay. This study demonstrated that infants with bronchiolitis that were treated with a nurse-led high-flow nasal cannula (HFNC) therapy protocol had positive effects on clinical outcomes including a shorter length of stay than compared with those with physician-directed care in a regional paediatric unit. A weight-based (2L/kg) HFNC therapy was safely administered to infants with bronchiolitis in a regional hospital paediatric ward with no paediatric intensive care unit (PICU).

Heated Humidified High-Flow Nasal Cannula in Children: State of the Art.

High-flow nasal cannula (HFNC) therapy is a non-invasive ventilatory support that has gained interest over the last ten years as a valid alternative to nasal continuous positive airway pressure (nCPAP) in children with respiratory failure. Its safety, availability, tolerability, and easy management have resulted its increasing usage, even outside intensive care units. Despite its wide use in daily clinical practice, there is still a lack of guidelines to standardize the use of HFNC. The aim of this review is to summarize current knowledge about the mechanisms of action, safety, clinical effects, and tolerance of HFNC in children, and to propose a clinical practices algorithm for children with respiratory failure.

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

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. 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. 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. 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.

Association between respiratory rate oxygenation index and need for positive pressure ventilation in children on high flow nasal cannula for bronchiolitis.

Our objective was to evaluate the association of respiratory rate oxygenation index (ROX) with the need for positive pressure ventilation in children < 2 years of age with bronchiolitis on high flow nasal cannula (HFNC) therapy. We performed a single-center prospective observational study of a convenience sample of children < 2 years of age with bronchiolitis who had HFNC initiated in the pediatric emergency department between November and March, 2018–2020. ROX was calculated as pulse oximetry/FiO2/respiratory rate at HFNC initiation. Demographics, need for positive pressure ventilation (PPV), disposition, and hospital length of stay were collected. Logistic regression model was used to determine the odds ratio for PPV need relative to the highest ROX quartile. Of the 373 patients included, 49 (13.1%) required PPV. ROX was lower in patients who required PPV compared with those who did not (5.86 [4.71–7.42] vs. 6.74 [5.46–8.25]; p = 0.01). Logistic regression revealed that those patients whose ROX was in the lowest quartile (< 5.39) were three times more likely to require PPV compared to those in the highest quartile (> 8.21). These results held true after adjusting for confounders (odds ratio 3.1; 95% CI [1.3 to 7.5]; p = 0.02). The model’s AUROC (0.701) indicated acceptable discrimination between cases and controls.Conclusion: Low ROX index was associated with the need for PPV in children with bronchiolitis on HFNC. The risk stratification provided and ROX threshold for risk stratification require confirmation in other populations with a larger sample size. What is Known:• Demographic and clinical factors associated with high flow nasal cannula (HFNC) therapy in children with bronchiolitis has been studied.What is New:• This is the first study to report the utility of association of Respiratory Rate Oxygenation (ROX) index for need for positive pressure ventilation (PPV) in children < 2 years of age with bronchiolitis on HFNC therapy.• ROX was lower in children who required PPV and children whose ROX was in the lowest quartile (< 5.39) were three times more likely to require PPV compared to those in the highest quartile (> 8.21).Supplementary InformationThe online version contains supplementary material available at 10.1007/s00431-022-04607-4.