Received High-flow Nasal Cannula Therapy Research Articles

A high-flow nasal cannula versus noninvasive ventilation in acute exacerbations of chronic obstructive pulmonary disease

PurposeWe investigated the efficacy and safety of a high-flow nasal cannula (HFNC) at different flow rates compared to noninvasive ventilation (NIV) in patients with acute chronic obstructive pulmonary disease (COPD) exacerbations. MethodsThis prospective, randomized, single-blind study assigned patients to one of three study groups. The NIV group (n = 47) received bilevel positive airway pressure. The HFNC-30 (n = 44) and HFNC-50 (n = 46) groups received HFNC therapy at flow rates of 30 and 50 L/min, respectively. Demographic and clinical characteristics and arterial blood gas parameters before and 30, 60, and 120 min after treatment were compared among the treatment groups. ResultsThis study included 137 consecutive patients with acute exacerbations of COPD, comprising 90 males and 47 females, with a mean age of 68.1 ± 10.5 years. A total of 21 patients (15.33 %) were intubated, and the overall mortality rate was 10.2 %. The mean PaCO2 levels on admission were 64.69 ± 10.81, 61.51 ± 9.03, and 62.29 ± 9.87 in the NIV, HFNC-30, and HFNC-50 groups, respectively, with no significant differences observed (p = 0.372). A significant reduction in mean PaCO2 was observed in all treatment groups at 30, 60, and 120 min (p < 0.05 for all). However, the ΔPaCO2 at 60 min was significantly higher in the HFNC-30 group compared to the NIV group (p = 0.042). Additionally, neither intubation rates nor 28-day mortality differed among the treatment groups (p = 0.368 and p = 0.775, respectively). ConclusionHFNC was not inferior to NIV in improving arterial blood gas parameters, particularly PaCO2 in patients with COPD exacerbations, especially those with hypercarbia. Moreover, HFNC at a flow rate of 30 L/min was superior to NIV for reducing PaCO2 levels at 60 min. Trial RegistryNational Library of Medicine Clinical Trial Registry; No.: NCT06495086; URL: https://clinicaltrials.gov/study/NCT06495086

Racial Differences in Accuracy of Predictive Models for High-Flow Nasal Cannula Failure in COVID-19.

To develop and validate machine learning (ML) models to predict high-flow nasal cannula (HFNC) failure in COVID-19, compare their performance to the respiratory rate-oxygenation (ROX) index, and evaluate model accuracy by self-reported race. Retrospective cohort study. Four Emory University Hospitals in Atlanta, GA. Adult patients hospitalized with COVID-19 between March 2020 and April 2022 who received HFNC therapy within 24 hours of ICU admission were included. None. Four types of supervised ML models were developed for predicting HFNC failure (defined as intubation or death within 7 d of HFNC initiation), using routine clinical variables from the first 24 hours of ICU admission. Models were trained on the first 60% (n = 594) of admissions and validated on the latter 40% (n = 390) of admissions to simulate prospective implementation. Among 984 patients included, 317 patients (32.2%) developed HFNC failure. eXtreme Gradient Boosting (XGB) model had the highest area under the receiver-operator characteristic curve (AUROC) for predicting HFNC failure (0.707), and was the only model with significantly better performance than the ROX index (AUROC 0.616). XGB model had significantly worse performance in Black patients compared with White patients (AUROC 0.663 vs. 0.808, p = 0.02). Racial differences in the XGB model were reduced and no longer statistically significant when restricted to patients with nonmissing arterial blood gas data, and when XGB model was developed to predict mortality (rather than the composite outcome of failure, which could be influenced by biased clinical decisions for intubation). Our XGB model had better discrimination for predicting HFNC failure in COVID-19 than the ROX index, but had racial differences in accuracy of predictions. Further studies are needed to understand and mitigate potential sources of biases in clinical ML models and to improve their equitability.

Use of high flow nasal cannula oxygen therapy for patients infected with SARS-CoV-2 outside intensive care setting.

In early 2022, there was a sudden surge of patients infected by the Omicron variant of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Hong Kong (HK), resulting in 9,163 deaths as of 29 May 2022. Many of the local population had not been vaccinated before this wave. The number of patients who developed coronavirus disease 2019 (COVID-19) related respiratory failure outnumbered the capacity of intensive care unit (ICU) beds. Some of these patients had to be supported with high flow nasal cannula (HFNC) therapy outside ICU setting. HK was in crisis situation. The primary objective of this study is to assess the 28-day mortality of this group of patients. The secondary objective is to explore any predictors of non-survivors to help clinical decision-making in future crisis. This is a retrospective observational study of patients suffering from COVID-19 related respiratory failure who received HFNC therapy in general medical wards of two hospitals during the period of 17 Mar to 30 Apr 2022. Survival and risk factors were reviewed. Forty-nine patients were recruited. Twenty-six patients (53%) survived at 28-day after initiation of HFNC support. Three clinical parameters were found to be significantly associated with mortality at 28-day: (I) SpO2/FiO2 (SF) ratio <160 at 48 hours; (II) SF ratio <191 at 72 hours; (III) serial SF ratio at 48 or 72 hours showing no improvement over that at the time of initiation of HFNC therapy. Use of HFNC outside ICU setting showed benefit to patients suffering from COVID-19 related acute hypoxemic respiratory failure (AHRF). Serial SF ratio monitoring at 48 and 72 hours after therapy initiation might serve as predictors of outcome and thus guide clinical decision-making for medical resource allocation in outbreak situation.

The Weaning Protocol of High Flow Nasal Cannula Reduce Duration of Weaning in Lower-Respiratory Tract Infection in Children Who Used High Flow Nasal Cannula: Single Center Experience in Thailand

Background: Use of high flow nasal cannula (HFNC) has been widely accepted as non-invasive respiratory support in children suffering from lower respiratory tract infections (LRI). Patients who use HFNC still need respiratory care from health personnel in ICU or intermediate care wards. Without the weaning protocol, the authors had noticed prolonged HFNC use, which affected the length of hospital stay (LOS). As such, a pediatric patient care team (PCT) created the weaning protocol and collected data whether the weaning protocol would shorten weaning time. Objective: To compare HFNC weaning times among children suffering from LRI, before and after using the weaning protocol. Materials and Methods: A pre- and post-intervention study of 1-month-old to 5-year-old children who received HFNC therapy for LRI at Panyananthaphikkhu Chonprathan Medical Center between August 2018 and July 2020, the one year before and after the protocol was implemented in August 2019, were carried out. Demographic data and severity of respiratory illness according to Respiratory Assessment Score (RAS) were recorded. Multivariate linear regression, adjusted for age, gender, weight, RR, HR, SpO₂, and RAS before using HFNC, was used to compare between the pre- and post-weaning protocol groups according to total HFNC time, duration of weaning time, and LOS. Results: There were 25 patients in each group. The mean age in the post-weaning protocol group was lower, but there was no difference in severity. Multivariate linear regression demonstrated that the post-weaning protocol group had a significantly shorter weaning time at 49.5±37.0 hours versus 84.2±62.8 hours (p=0.034). Moreover, total HFNC time was also significantly shorter in the post-weaning protocol group at 71.53±36.7 hours versus 119.6±78.2 hours (p=0.019). There was no difference in vital signs during weaning between the two groups. Conclusion: Implementing the weaning protocol reduce weaning time and total HFNC time, without affecting clinical outcomes. Keywords: High flow nasal cannula; Weaning protocol; Lower respiratory tract infection; Length of stay

Use of high-flow nasal cannula oxygen therapy for patients with terminal cancer at the end of life.

Few studies have focused on high-flow nasal cannula (HFNC) usage in the last few weeks of life. The aim of this study was to identify the status of HFNC use in patients with cancer at the end of life and the relevant clinical factors. We performed a retrospective cohort study in a tertiary hospital in the Republic of Korea. Among patients with cancer who died between 2018 and 2020, those who initiated HFNC within 14 days before death were included. Patients were categorized based on the time from HFNC initiation to death as imminent (<4 days) and non-imminent (≥4 days). Among the 2191 deceased patients with terminal cancer, 329 (15.0%) were analyzed. The median age of the patients was 66 years, and 62.9% were male. The leading cause of respiratory failure was pneumonia (70.2%), followed by pleural effusion (30.7%) and aggravation of lung neoplasms (18.8%). Most patients were conscious (79.3%) and had resting dyspnea (76.3%) at HFNC initiation. Patients received HFNC therapy for a mean of 3.4 days in the last 2 weeks of life, and 62.6% initiated it within 4 days before death. Furthermore, female sex, no palliative care consultation, no advance statements in person on life-sustaining treatment, and no resting dyspnea were independently associated with the imminent use of HFNC. Many patients with cancer started HFNC therapy at the point of imminent death. However, efforts toward goal-directed use of HFNC at the end-of-life stage are required.

The effects of high-flow nasal cannula oxygen therapy in dyspnea patients with and without hypercapnia in the emergency department: a retrospective, propensity score-matched cohort study

We aimed to study the difference in treatment outcomes and prognoses in patients with or without hypercapnia who visited the emergency department for dyspnea and received high-flow nasal cannula (HFNC) therapy. This was a retrospective observational study. Patients who received HFNC therapy were divided into hypercapnic and non-hypercapnic. The intubation rates were compared for the primary outcome. For the secondary outcomes, intensive care unit (ICU) admission, length of hospital stay, length of ICU stay, and mortality were compared. Moreover, changes in arterial blood gas results were reported in terms of group, time, and group-by-time interaction. A total of 517 patients were enrolled, of whom 126 were included in the hypercapnic group. After propensity score matching, 94 patients were selected. The intubation rate was not significantly different between the two groups (p = 0.23). No differences were found in ICU admission, length of hospital stay, length of ICU stay, and mortality. The changes in arterial blood gas results pre- and post-HFNC therapy showed a difference in the group-by-time interaction for partial pressure of carbon dioxide (p = 0.038). We found that there was no difference in treatment outcomes and prognoses in patients with or without hypercapnia who visited the emergency department for dyspnea and received HFNC therapy.

Comparison of the effectiveness of high-flow and conventional nasal cannula oxygen therapy in pulmonary embolism patients with acute hypoxemic respiratory failure.

The leading cause of mortality in pulmonary embolism (PE) is hypoxemic respiratory failure. The aim of this study was to compare the efficacy of high-flow nasal cannula (HFNC) and conventional nasal cannula (CNC) oxygen therapy in PE patients with hypoxemia. Fifty-eight patients with a PaO2/FIO2 ratio below 300 who were admitted to the emergency department with acute respiratory distress and followed up in our intensive care unit due to PE between March and October 2019 were included in the study. One group (n= 29) received HFNC oxygen therapy and the other group (n= 29) received CNC oxygen therapy. Arterial blood gas analysis showed no significant differences in baseline SpO2 and PaO2 between the HFNC and CNC groups, whereas both values were significantly higher in the HFNC group starting at 1 hour (PaO2: p= .01, p= .001, p= .001; SpO2: p= .009, p= .005, p= .002). Among massive PE patients with contraindications for thrombolytic therapy, there was no significant difference between the HFNC and CNC groups in baseline SpO2, PaO2, or respiratory rate, but those who received HFNC therapy had significant higher SpO2 starting at 15 minutes (p= .004 for all), significantly higher PaO2 starting at 1 hour (p= .01, p= .001, p= .001), and significantly lower respiratory rate starting at 30 minutes (p= .003, p= .001, p= .001, p= .002, p= .002). In patients presenting with PE and hypoxemic respiratory failure, HFNC oxygen therapy was more effective on both vital signs and arterial blood gas parameters compared to conventional oxygen therapy and can be used safely as primary treatment.

High-flow nasal cannula therapy in a predominantly African American population with COVID-19 associated acute respiratory failure

ImportanceUse of non-invasive respiratory modalities in COVID-19 has the potential to reduce rates of intubation and mortality in severe disease however data regarding the use of high-flow nasal cannula (HFNC)...

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

BackgroundHigh flow nasal cannula (HFNC) is a new device for respiratory support. Its use continues to increase in pediatrics as its system is easily set up and well tolerated by patients. We aimed in this study to explore indications and safety of HFNC use and predictors of HFNC failure.MethodsHospital records of 92 children with acute respiratory distress admitted to the pediatric intensive care unit (PICU) in Abha Maternity and Children Hospital from January 2018 until March 2020 and received HFNC therapy were studied. A data collection sheet was used that included patients’ age, gender, the indication of HFNC, associated chronic diseases, previous admission to PICU, vital signs (initially, 8 hours and 48 hours after using HFNC), outcome after using HFNC, and reasons for HFNC failure.ResultsAfter receiving HFNC, children’s respiratory rate, heart rate, systolic blood pressure, and oxygen saturation improved significantly (p < 0.001, p < 0.001, p < 0.001, p = 0.005, and p < 0.001, respectively). Regarding laboratory findings, pH and serum bicarbonate improved significantly (p < 0.001 for both), while PaCO2 improved but not significantly. The failure rate of HFNC was 23.0%. HFNC failure rates were significantly higher among children with chronic diseases than those with no chronic disease (33.3% and 14.9%, respectively, p = 0.038) and among children with the air-leak syndrome (p < 0.001). After 48 hours of HFNC use, children who experienced HFNC failure had significantly higher respiratory and heart rates (p < 0.001 and p = 0.018, respectively), lower diastolic blood pressure (p = 0.011), and higher PaCO2 (p < 0.001).ConclusionAfter HFNC use, significant improvements occur in all clinical parameters and laboratory values of children with respiratory distress, but about one-fourth of cases may experience HFNC failure. Predictors for HFNC failure include underlying chronic disease, low diastolic blood pressure, high respiratory rate, high heart rate, high initial PaCO2.

A pediatric high-flow nasal cannula protocol standardizes initial flow and expedites weaning.

Respiratory illnesses compose the most common diagnoses of patients admitted to pediatric intensive care units. In pediatrics, high-flow nasal cannula (HFNC) therapy is an intermediate level of respiratory support with variability in practice. We conducted a pre-post intervention study of patients placed on HFNC therapy before and after the implementation of anHFNC protocol. This was a quality improvement/pre-post intervention study of pediatric patients who received HFNC therapy in our teaching, tertiary care children's hospital between January 2015 and April 2019. Patients were evaluated before and after the implementation of a protocol that promoted initiation of higher flow and rapid weaning. Our primary outcomes were initial flow and rate of weaning pre- and post-protocol; our secondary outcomes were HFNC failure rate (defined as escalation to noninvasive ventilation or mechanical ventilation) and length of hospital stay. Propensity matching was used to account for differences in age and weight pre- and post-protocol. In total, 584 patients were included, 292 pre-protocol,and 292 post-protocol. The median age was 20 months, and the indication for HFNC therapy was bronchiolitis in 29% of patients. Post-protocol patients compared to pre-protocol patients had significantly a higher initial flow (median 14.5 L/min vs. 10 L/min, p < .001) and a higher weaning rate of flow (median 4.1 L/min/hvs. 2.4 L/min/h, p < .001). Post-protocol patients also had a lower HFNC failure rate (10% vs. 17%, p = .015) and a shorter length of stay (5.97 days vs. 6.80 days, p = .006). Among pediatric patients, the implementation of an HFNC protocol increases initial flow, allows for more rapid weaning, and may decrease the incidence of escalation to noninvasive ventilation or mechanical ventilation.

High Flow Nasal Cannula Therapy in Children with Acute Respiratory Insufficiency in the Pediatric Intensive Care Unit of a Resource-limited Country: A Preliminary Experience.

A retrospective study was performed in children (aged one month - 16 years) receiving HFNC to determine the frequency, efficacy and adverse effects of high flow nasal cannula (HFNC) therapy in the pediatric intensive care unit (PICU), from January to December 2017. Treatment failure was defined as clinical deterioration on HFNC therapy such that mechanical ventilation (MV) was required. Clinical parameters before and after HFNC were assessed using repeated measures analysis of variance. A total of 120 patients received HFNC therapy (21% of total admissions). Primary diagnosis were respiratory disease (50%), central nervous system diseases (14.2%), sepsis (10.8%), and postoperative care (10%). Mean duration of HFNC was 27.5 ±19.7hours and mean PICU length of stay was 6 ± 6 days. Pneumothorax developed in four patients. MV was required in 28 patients, and subsequently, 15 deaths occurred in that group. HFNC is a frequently used, safe and effective therapy for children requiring respiratory support in PICU. Key Words: Respiratory insufficiency, Non-invasive ventilation, Paediatric intensive care unit.

Predicting nasal high-flow therapy failure by pediatric respiratory rate-oxygenation index and pediatric respiratory rate-oxygenation index variation in children.

The primary objective of this study was to evaluate whether pediatric respiratory rate-oxygenation index (p-ROXI) and variation in p-ROXI (p-ROXV) can serve as objective markers in children with high-flow nasal cannula (HFNC) failure. In this prospective, single-center observational study, all patients who received HFNC therapy in the general pediatrics ward, pediatric intensive care unit, and the pediatric emergency department were included. High-flow nasal cannula success was achieved for 116 (88.5%) patients. At 24h, if both p-ROXI and p-ROXV values were above the cutoff point (≥ 66.7 and ≥ 24.0, respectively), HFNC failure was 1.9% and 40.6% if both were below their values (p < 0.001). At 48h of HFNC initiation, if both p-ROXI and p-ROXV values were above the cutoff point (≥ 65.1 and ≥ 24.6, respectively), HFNC failure was 0.0%; if both were below these values, HFNC failure was 100% (p < 0.001).Conclusion: We observed that these parameters can be used as good markers in pediatric clinics to predict the risk of HFNC failure in patients with acute respiratory failure. What is Known: • Optimal timing for transitions between invasive and noninvasive ventilation strategies is of significant importance. • The complexity of data requires an objective marker that can be evaluated quickly and easily at the patient's bedside for predicting HFNC failure in children with acute respiratory failure. What is New: • Our data showed that combining p-ROXI and p-ROXV can be successful in predicting HFNC failure at 24 and 48h of therapy.

High-flow nasal cannula therapy for acute respiratory failure in patients with chest trauma: A single-center retrospective study

PurposeThis retrospective study was performed to investigate the utility of high-flow nasal cannula (HFNC) therapy in patients with chest trauma and identify the risk factors associated with treatment failure. Materials and methodsWe identified 44 acute respiratory failure patients with chest trauma who received HFNC therapy between June 2016 and March 2019 at the Fourth Affiliated Hospital of Nantong University. According to their response to HFNC therapy, the patients were divided into success and failure groups. Their medical records were reviewed retrospectively to identify useful risk factors for HFNC treatment failure. ResultsOf the 44 patients, 25 and 19 patients were assigned to the HFNC success and failure groups, respectively. Compared with the success group, the failure group had a significantly higher rate of multiple rib fractures/flail chest (P = 0.035), higher Thoracic Trauma Severity Score (TTSS) (P = 0.001) and significantly longer ICU stay (P = 0.006) and hospital stay (P = 0.001). The mortality rate of the failure group was higher than that of the success group, but there was no significant difference (P = 0.414). High TTSS was a significant risk factor for treatment failure. The AUC of TTSS was 0.793. The cut-off value for TTSS was 14 points (sensitivity: 0.68, specificity: 0.84). ConclusionsHFNC therapy was safe and effective in patients with chest trauma, and more than 50% of the patients successfully recovered from acute respiratory failure without invasive ventilation. A high TTSS could be a significant risk factor for HFNC treatment failure and had a high predictive performance.

Effect of High-Flow Nasal Cannula on Sleep-disordered Breathing and Sleep Quality in Patients With Acute Stroke.

IntroductionSleep-disordered breathing (SDB) is common after stroke. Although the standard treatment of SDB is continuous positive airway pressure (CPAP) ventilation, the patient’s intolerance and discomfort result in low adherence rates. Alternatively, high-flow nasal cannula (HFNC) may be useful as it reduces upper airway collapse with low level of positive pressure and well tolerability. The aim of this study was to investigate whether HFNC therapy reduces SDB and improves sleep quality with higher compliance rate.MethodsWe included acute stroke patients with SDB for the assessment of apnea-hypopnea index (AHI) >5/h using WatchPAT 200 (Itamar Medical Ltd, Caesarea, Israel). Patients who met inclusion criteria received HFNC therapy (40 L/min) with monitoring by WatchPAT. AHI, oxygen desaturation index (ODI), sleep efficiency, and rapid eye movement (REM) sleep were compared in patients with and without HFNC therapy. We also evaluated the patient’s comfort of HFNC therapy (discomfort or not).ResultsAmong 17 patients assessed for AHI, 12 received HFNC therapy. HFNC therapy was not adhered in two patients due to intolerance. Eight patients remained for final analysis. There were no differences in SDB and sleep quality with and without HFNC therapy as follows: HFNC therapy vs control; AHI 24.9 ± 20.1 vs 21.3 ± 15.0/h (p = 0.63), ODI 16.2 ± 16.5 vs 12.9 ± 12.3/h (p = 0.54), sleep efficiency 80.4 ± 12.9 vs 87.1 ± 6.2 (p = 0.28), percentage of REM sleep 19.4% ± 9.6% vs 27.6% ± 8.9% (p = 0.07). Two patients (17%) complained of discomfort among eight patients.ConclusionHFNC therapy did not improve SDB and sleep quality. Nonadherence and discomfort were observed in HFNC therapy. We need a large trial to confirm this result.

High-flow nasal cannula therapy reduced the respiratory rate and respiratory distress in a standard model simulator and in patients with hypoxemic respiratory failure.

High-flow nasal cannula (HFNC) therapy has been increasingly applied to treat patients with severe hypoxemic respiratory failure. We investigated whether vital signs reflect the reduction of work of breathing in a simulator study and a clinical study. In the simulator study, a standard model high-fidelity human patient simulator (HPS) directly received 35 L/minute of 100% O2 via the HFNC. In the clinical study, the medical records of patients with hypoxemic respiratory failure who received HFNC therapy between January 2013 and May 2015 were retrospectively reviewed. Statistical analysis was performed using a one-way repeated analysis of variance followed by Bonferroni post-hoc testing. In the HPS, HFNC therapy significantly reduced the partial pressure of alveolar CO2, respiratory rate, and tidal volume (p < 0.001), and all values returned to baseline following HFNC therapy termination (p < 0.001). In the clinical study including 48 patients, the respiratory rate was significantly reduced from 27 ± 9 (baseline) to 24 ± 8 (3 hours), 24 ± 8 (5 hours), and 24 ± 8.0 (6 hours) (p < 0.05). The heart rate also decreased significantly (p < 0.05). Our results suggested that HFNC therapy reduced work of breathing and assessing vital signs can be important.

Feasibility of high-flow nasal cannula oxygen therapy for acute respiratory failure in patients with hematologic malignancies: A retrospective single-center study

PurposeThis study investigated the feasibility of high-flow nasal cannula (HFNC) oxygen therapy for acute respiratory failure in adult patients with hematologic malignancies. Materials and methodsWe identified 45 acute respiratory failure patients with hematologic malignancies who received HFNC therapy between March 2012 and June 2014 at Seoul St Mary's Hospital. Their medical records were reviewed retrospectively to identify useful prognostic factors for successful treatment. ResultsOf the 45 patients, 15 (33.3%) successfully recovered, and 30 were changed to invasive ventilation due to failed HFNC treatment. The etiologies of acute respiratory failure were bacterial pneumonia (57.8%), Pneumocystis jirovecii pneumonia (17.8%), pulmonary edema (8.9%), and bronchiolitis obliterans organizing pneumonia (8.9%). The overall mortality rate was 62.2%. The HFNC treatment success rate was significantly different between the survivors and nonsurvivors. To evaluate risk factors for HFNC treatment failure, differences between the HFNC treatment success and failure groups were compared. There were no significant differences in the severity of underlying medical conditions. The percentage of bacterial pneumonia was significantly higher in the HFNC treatment failure group compared with the success group (73.3% vs 26.7%; P = .004). ConclusionsHigh-flow nasal cannula offers an interesting alternative to invasive ventilation in acute respiratory failure patients with hematologic malignancies. However, attention must be paid to the appropriate choice of HFNC settings such as oxygen flow.

Failure of high-flow nasal cannula therapy may delay intubation and increase mortality.

Intubation in patients with respiratory failure can be avoided by high-flow nasal cannula (HFNC) use. However, it is unclear whether waiting until HFNC fails, which would delay intubation, has adverse effects. The present retrospective observational study assessed overall ICU mortality and other hospital outcomes of patients who received HFNC therapy that failed. All consecutive patients in one tertiary hospital who received HFNC therapy that failed and who then required intubation between January 2013 and March 2014 were enrolled and classified according to whether intubation started early (within 48h) or late (at least 48h) after commencing HFNC. Of the 175 enrolled patients, 130 (74.3%) and 45 (25.7%) were intubated before and after 48h of HFNC, respectively. The groups were similar in terms of most baseline characteristics. The early intubated patients had better overall ICU mortality (39.2 vs. 66.7%; P=0.001) than late intubated patients. A similar pattern was seen with extubation success (37.7 vs. 15.6%; P=0.006), ventilator weaning (55.4 vs. 28.9%; P=0.002), and ventilator-free days (8.6±10.1 vs. 3.6±7.5; P=0.011). In propensity-adjusted and -matched analysis, early intubation was also associated with better overall ICU mortality [adjusted odds ratio (OR)=0.317, P=0.005; matched OR=0.369, P=0.046]. Failure of HFNC might cause delayed intubation and worse clinical outcomes in patients with respiratory failure. Large prospective and randomized controlled studies on HFNC failure are needed to draw a definitive conclusion.

High-Flow Nasal Cannula Use in Children With Respiratory Distress in the Emergency Department

High-flow nasal cannula (HFNC) is a safe, well-tolerated, and noninvasive method of respiratory support that has seen increasing use in the care of children with respiratory distress. High-flow nasal cannula may be able to prevent intubations in infants and children with respiratory distress. The objective of this study was to determine the clinical and patient characteristics that predict success or failure of HFNC therapy in children presenting to the pediatric emergency department (PED) with respiratory distress. A retrospective cohort review was conducted of all children younger than 2 years evaluated in 2 PEDs between June 2011 and September 2012 who received HFNC therapy within 24 hours of initial triage. Data extraction included clinical variables, demographic variables, and patient outcomes. Therapy failure was defined as the clinical decision to intubate a patient after an antecedent trial of HFNC. Multivariable logistic regression was performed to identify factors associated with intubation following HFNC. Four hundred ninety-eight cases meeting criteria for inclusion were identified. The most common final diagnosis was acute bronchiolitis (n = 231, 46%), followed by pneumonia (n = 138, 28%) and asthma (n = 38, 8%). Of the 498 patients, 42 (8%) of patients failed therapy and required intubation following HFNC trial. Risk factors associated with HFNC failure were triage respiratory rate greater than 90th percentile for age (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.01-4.43), initial venous PCO2 greater than 50 mm Hg (OR, 2.51; 95% CI, 1.06-5.98), and initial venous pH less than 7.30 (OR, 2.53; 95% CI, 1.12-5.74). A final diagnosis of bronchiolitis was observed to be protective with respect to intubation (OR, 0.40; 95% CI, 0.17-0.96). In infants with all-cause respiratory distress presenting in the PED, triage respiratory rate greater than 90th percentile for age, initial venous PCO2 greater than 50 mm Hg, and initial venous pH less than 7.30 were associated with failure of HFNC therapy. A diagnosis of acute bronchiolitis was protective with respect to intubation following HFNC. This finding may help guide clinicians who use HFNC by identifying a patient population at higher risk of failing therapy.