High-flow Nasal Cannula Failure Research Articles

Predictors of high-flow nasal cannula failure in COVID-19 patients in a northern Peruvian hospital

ObjectivesTo determine predictors of high-flow nasal cannula (HFNC) failure in COVID-19 patients in a hospital in northern Peru.MethodologyA retrospective cohort study was conducted during the months of March and May 2021. Data collection was based on a follow-up of 156 hospitalized patients with a diagnosis of COVID-19 who were users of HFNC. Epidemiological factors and clinical outcomes of treatment were analyzed from medical records. Epidemiological, analytical, and HFNC use-related characteristics were described using measures of absolute and relative frequencies, measures of central tendency, and dispersion. A multivariate Poisson regression analysis with robust variance and a 95% confidence interval was performed.ResultsWe found that age, SpO2/FiO2, work of breathing (WOB scale) at admission, degree of involvement, type of infiltrate on CT scan, lymphocytes, c-reactive protein, and D-dimer were significantly associated with failure of HFNC (p < 0.05). In addition, the WOB scale, PaO2/FiO2, SaO2/FiO2, and ROX index were variables that presented statistical significance (p < 0.0001). In the multivariate analysis model, a risk of failure of HFNC was determined with age > = 60 years [RRa 1.39 (1.05–1.85)] and PaO2/FiO2 score less than 100 [Rra 1.65 (0.99–2.76)].ConclusionsPredictors to failure of HFNC are age older than 60 years and minimally significantly lower PaO2/FiO2 than 100.

A comparison study of temporal trends of SARS-CoV2 RNAemia and biomarkers to predict success and failure of high flow oxygen therapy among patients with moderate to severe COVID-19.

Optimal timing for intubating patients with coronavirus disease 2019 (COVID-19) has been debated throughout the pandemic. Early use of high-flow nasal cannula (HFNC) can help reduce the need for intubation, but delay can result in poorer outcomes. This study examines trends in laboratory parameters and serum severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA levels of patients with COVID-19 in relation to HFNC failure. Patients requiring HFNC within three days of hospitalization between July 1 and September 30, 2021 were enrolled. The primary outcome was HFNC failure (early failure ≤Day 3; late failure ≥Day 4), defined as transfer to intensive care just before/after intubation or in-hospital death. We examined changes in laboratory markers and SARS-CoV2-RNAemia on Days 1, 4, and 7, together with demographic data, oxygenation status, and therapeutic agents. We conducted a univariate logistic regression with the explanatory variables defined as 10% change rate in each laboratory marker from Day 1 to 4. We utilized the log-rank test to assess the differences in HFNC failure rates, stratified based on the presence of SARS-CoV2 RNAemia. Among 122 patients, 17 (13.9%) experienced HFNC failure (early: n = 6, late: n = 11). Seventy-five patients (61.5%) showed an initial SpO2/FiO2 ratio ≤243, equivalent to PaO2/FiO2 ratio ≤200, and the initial SpO2/FiO2 ratio was significantly lower in the failure group (184 vs. 218, p = 0.018). Among the laboratory markers, a 10% increase from Day 1 to 4 of lactate dehydrogenase (LDH) and interleukin (IL)-6 was associated with late failure (Odds ratio [OR]: 1.42, 95% confidence interval [CI]: 1.09-1.89 and OR: 1.04, 95%CI: 1.00-1.19, respectively). Furthermore, in patients with persistent RNAemia on Day 4 or 7, the risk of late HFNC failure was significantly higher (Log-rank test, p<0.01). In conclusion, upward trends in LDH and IL-6 levels and the persistent RNAemia even after treatment were associated with HFNC failure.

High-flow nasal cannula oxygen therapy for mild-moderate acute respiratory failure in patients with blunt chest trauma: An exploratory descriptive study

ObjectiveThe use of high-flow nasal cannula (HFNC) oxygen therapy is gaining popularity for the treatment of acute respiratory failure (ARF). However, limited evidence exists regarding the effectiveness of HFNC for hypoxemic ARF in patients with blunt chest trauma (BCT). MethodsThis retrospective analysis focused on BCT patients with mild-moderate hypoxemic ARF who were treated with either HFNC or non-invasive ventilation (NIV) in the emergency medicine department from January 2021 to December 2022. The primary endpoint was treatment failure, defined as either invasive ventilation, or a switch to the other study treatment (NIV for patients in the NFNC group, and vice-versa). ResultsA total of 157 patients with BCT (72 in the HFNC group and 85 in the NIV group) were included in this study. The treatment failure rate in the HFNC group was 11.1% and 16.5% in the NIV group - risk difference of 5.36% (95% CI, −5.94–16.10%; P = 0.366). The most common cause of failure in the HFNC group was aggravation of respiratory distress. While in the NIV group, the most common reason for failure was treatment intolerance. Treatment intolerance in the HFNC group was significantly lower than that in the NIV group (1.4% vs 9.4%, 95% CI 0.40–16.18; P = 0.039). Univariate logistic regression analysis showed that chronic respiratory disease, abbreviated injury scale score (chest) (≥3), Acute Physiology and Chronic Health Evaluation II score (≥15), partial arterial oxygen tension /fraction of inspired oxygen (≤200) at 1 h of treatment and respiratory rate (≥32 /min) at 1 h of treatment were risk factors associated with HFNC failure. ConclusionIn BCT patients with mild-moderate hypoxemic ARF, the usage of HFNC did not lead to higher rate of treatment failure when compared to NIV. HFNC was found to offer better comfort and tolerance than NIV, suggesting it may be a promising new respiratory support therapy for BCT patients with mild-moderate ARF.

Failure Prediction of High-Flow Nasal Cannula at the Conventional Oxygen Therapy Phase in the Emergency Department

Introduction: The use of high-flow nasal cannula (HFNC) in patients with acute hypoxemic respiratory failure has been increasing in the emergency department (ED). However, studies are lacking on the prediction of HFNC failure before therapy initiation in the ED. We investigated whether the existing indices, such as the ratio of pulse oximetry oxygen saturation/fraction of inspired oxygen to respiratory rate (ROX) and ratio of ROX index to heart rate (ROX-HR), can accurately predict HFNC failure at the conventional oxygen therapy phase in the ED. Methods: This retrospective single-center study included patients treated with HFNC in the ED. The ROX and ROX-HR indices were calculated before initiating HFNC. An estimated fraction of inspired oxygen was used for conventional oxygen therapy. We plotted each index’s receiver operating characteristics curve and calculated the area under the curve (AUC) for diagnostic capacity. The optimal cutoff values were assessed using the Youden index. The primary outcome was HFNC failure, defined as intubation in the ED. Results: Among the 97 included patients, 25 (25.8%) failed HFNC therapy in the ED. The ROX and ROX-HR indices measured before initiating HFNC showed AUCs of 0.709 and 0.754, respectively. A ROX index of <5.614 and a ROX-HR index of <6.152 were associated with a high risk of intubation, even after correcting for confounding variables. Conclusion: The ROX and ROX-HR indices measured before initiating HFNC provide a relatively fair predictive value of HFNC failure in the ED.

High-flow nasal cannula oxygen therapy is equally effective to noninvasive ventilation for mild-moderate acute respiratory distress syndrome in patients with acute pancreatitis: A single-center, retrospective cohort study.

The use of high-flow nasal cannula (HFNC) oxygen therapy is gaining popularity for the treatment of acute hypoxic respiratory failure. However, limited evidence exists regarding the effectiveness of HFNC for acute respiratory distress syndrome (ARDS) in patients with acute pancreatitis (AP). This retrospective analysis focused on AP patients with mild-moderate ARDS, who were treated with either HFNC or noninvasive ventilation (NIV) in the emergency medicine department, from January 2020 to December 2022. The primary endpoint was treatment failure, defined as either invasive ventilation or a switch to any other study treatment (NIV for patients in the NFNC group and vice versa). A total of 146 patients with AP (68 in the HFNC group and 78 in the NIV group) were included in this study. The treatment failure rate in the HFNC group was 17.6% and 19.2% in the NIV group - a risk difference of -1.6% (95% CI, -11.3 to 14.0%; P = 0.806). The most common causes of failure in the HFNC group were aggravation of respiratory distress and hypoxemia. However, in the NIV group, the most common reasons for failure were treatment intolerance and exacerbation of respiratory distress. Treatment intolerance in the HFNC group was significantly lower than that in the NIV group (16.7% vs 60.0%, 95% CI -66.8 to -6.2; P = 0.023). Multivariate logistic regression analysis showed that body mass index (≥28), acute physiology and chronic health evaluation II score (≥15), partial arterial oxygen tension/fraction of inspired oxygen (≤200), and respiratory rate (≥32/min) at 1 hour were independent predictors of HFNC failure. In AP patients with mild-moderate ARDS, the usage of HFNC did not lead to a higher rate of treatment failure when compared to NIV. HFNC is an ideal choice of respiratory support for patients with NIV intolerance, but clinical application should pay attention to the influencing factors of its treatment failure.

Respiratory Support Practices for Bronchiolitis in the Pediatric Intensive Care Unit

Admissions to the pediatric intensive care unit (PICU) due to bronchiolitis are increasing. Whether this increase is associated with changes in noninvasive respiratory support practices is unknown. To assess whether the number of PICU admissions for bronchiolitis between 2013 and 2022 was associated with changes in the use of high-flow nasal cannula (HFNC), noninvasive ventilation (NIV), and invasive mechanical ventilation (IMV) and to identify factors associated with HFNC and NIV success and failure. This cross-sectional study examined encounter data from the Virtual Pediatric Systems database on annual PICU admissions for bronchiolitis and ventilation practices among patients aged younger than 2 years admitted to 27 PICUs between January 1, 2013, and December 31, 2022. Use of HFNC and NIV was defined as successful if patients were weaned to less invasive support (room air or low-flow nasal cannula for HFNC; room air, low-flow nasal cannula, or HFNC for NIV). The main outcome was the number of PICU admissions for bronchiolitis requiring the use of HFNC, NIV, or IMV. Linear regression was used to analyze the association between admission year and absolute numbers of encounters stratified by the maximum level of respiratory support required. Multivariable logistic regression was used to analyze factors associated with HFNC and NIV success and failure (defined as not meeting the criteria for success). Included in the analysis were 33 816 encounters for patients with bronchiolitis (20 186 males [59.7%]; 1910 patients [5.6%] aged ≤28 days and 31 906 patients [94.4%] aged 29 days to <2 years) treated at 27 PICUs from 2013 to 2022. A total of 7615 of 15 518 patients (49.1%) had respiratory syncytial virus infection and 1522 of 33 816 (4.5%) had preexisting cardiac disease. Admissions to the PICU increased by 350 (95% CI, 170-531) encounters annually. When data were grouped by the maximum level of respiratory support required, HFNC use increased by 242 (95% CI, 139-345) encounters per year and NIV use increased by 126 (95% CI, 64-189) encounters per year. The use of IMV did not significantly change (10 [95% CI, -11 to 31] encounters per year). In all, 22 381 patients (81.8%) were successfully weaned from HFNC to low-flow oxygen therapy or room air, 431 (1.6%) were restarted on HFNC, 3057 (11.2%) were escalated to NIV, and 1476 (5.4%) were escalated to IMV or extracorporeal membrane oxygenation (ECMO). Successful use of HFNC increased from 820 of 1027 encounters (79.8%) in 2013 to 3693 of 4399 encounters (84.0%) in 2022 (P = .002). In all, 8476 patients (81.5%) were successfully weaned from NIV, 787 (7.6%) were restarted on NIV, and 1135 (10.9%) were escalated to IMV or ECMO. Success with NIV increased from 224 of 306 encounters (73.2%) in 2013 to 1335 of 1589 encounters (84.0%) in 2022 (P < .001). In multivariable logistic regression, lower weight, higher Pediatric Risk of Mortality III score, cardiac disease, and PICU admission from outside the emergency department were associated with greater odds of HFNC and NIV failure. Findings of this cross-sectional study of patients aged younger than 2 years admitted for bronchiolitis suggest there was a 3-fold increase in PICU admissions between 2013 and 2022 associated with a 4.8-fold increase in HFNC use and a 5.8-fold increase in NIV use. Further research is needed to standardize approaches to HFNC and NIV support in bronchiolitis to reduce resource strain.

Outcome of high-flow nasal cannula (HFNC) therapy in respiratory failure due to lower respiratory tract infections in PICU - a single center experience in Karachi, Pakistan.

Objective: To evaluate the outcome of high-flow nasal cannula (HFNC) therapy by ROX index in critically ill children with acute respiratory failure due to lower respiratory tract infections in pediatric intensive care unit (PICU). Study Design: Analytical, Observational, Cross-sectional study. Setting: The PICU of the Indus Hospital, Karachi, Pakistan. Period: November 2022 to October 2023. Methods: We enrolled children of either gender, aged above 1 month up to 16 years and presenting with acute respiratory insufficiency due to lower respiratory tract infections. The use of HFNC was monitored for 72-hours. HFNC failure was characterized by requiring either noninvasive mechanical ventilation or invasive mechanical ventilation due to an unstable state. Results: In a total of 62 children, 39 (62.9%) were male. The mean age was 27.01±30.96 months. The most common diagnosis at the time of admission were pneumonia, and bronchiolitis noted in 25 (40.3%), and 33 (53.2%) children, respectively. Gradual improvement in ROX index was observed among children with HFNC success while a declining ROX index predicted HFNC failure. Outcome of HFNC was successful in 45 (72.6%) children. Mortality was observed in 12 (19.4%) children. Presence of comorbidity was significantly associated with unsuccessful HFNC outcomes. Conclusion: ROX index was found to be a good predictor of HFNC outcome. Overall, HFNC therapy in PICU demonstrated 72.6% success rate. HFNC outcomes are hampered particularly in cases involving comorbidities highlighting the need for tailored interventions.

Factors influencing the therapeutic failure of high-flow nasal cannula oxygen humidification in patients with interstitial pneumonia complicated by respiratory failure.

The aim of this study was to explore the factors influencing the treatment failure of high-flow nasal cannula (HFNC) therapy in patients with interstitial pneumonia (IP) complicated by respiratory failure. A total of 158 patients with IP and respiratory failure treated with HFNC in our hospital from January 2020 to August 2023 were selected as the study population. Based on treatment efficacy, they were categorized into the HFNC treatment failure group and the HFNC treatment success group. Clinical data were compared between the two groups. Multiple logistic regression analysis was employed to identify independent factors influencing treatment failure, and the predictive value of these factors for HFNC treatment failure was assessed using receiver operating characteristic (ROC) curve analysis. After 7 days of HFNC treatment, among the 158 patients with IP and respiratory failure, 25 (15.8%) declared treatment failure, while the remaining 133 (84.2%) showed treatment success. Patients in the HFNC treatment failure group had significantly higher age, duration of IP, pre-treatment respiratory rate, C-reactive protein (CRP), and controlling nutritional status (CONUT) scores compared to the HFNC treatment success group. The PaO2/FiO2 ratio, left ventricular ejection fraction, and Glasgow Coma Scale (GCS) were significantly lower in the HFNC treatment failure group (p<0.05). Multiple logistic regression analysis revealed that pre-treatment PaO2/FiO2 ratio, CRP, CONUT, and GCS scores were independent factors influencing HFNC treatment failure in patients with IP and respiratory failure (p<0.05). Lower PaO2/FiO2 ratio and GCS scores, and higher CRP and CONUT scores were associated with an increased risk of HFNC treatment failure. ROC curve analysis indicated that pre-treatment PaO2/FiO2 ratio, CRP, CONUT, and GCS scores in patients with IP and respiratory failure had a high predictive value for HFNC treatment failure (p<0.05). The HFNC failure rate in patients with IP and respiratory failure is 15.8%. Pre-treatment PaO2/FiO2 ratio, CRP, CONUT, and GCS scores are independent factors associated with HFNC treatment failure and warrant clinical attention.

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.

Lung ultrasound score predicts outcomes in patients with acute respiratory failure secondary to COVID-19 treated with non-invasive respiratory support: a prospective cohort study

BackgroundLung ultrasound has demonstrated its usefulness in several respiratory diseases management. One derived score, the Lung Ultrasound (LUS) score, is considered a good outcome predictor in patients with Acute Respiratory Failure (ARF). Nevertheless, it has not been tested in patients undergoing non-invasive respiratory support (NIRS). Taking this into account, the aim of this study is to evaluate LUS score as a predictor of 90-day mortality, ETI (Endotracheal intubation) and HFNC (High Flow Nasal Cannula) failure in patients with ARF due to COVID-19 admitted to a Respiratory Intermediate Care Unit (RICU) for NIRS management.ResultsOne hundred one patients were admitted to the RICU during the study period. Among these 76% were males and the median age was 55 (45–64) years. Initial ARF management started with HFNC, the next step was the use of Continuous Positive Airway Pressure (CPAP) devices and the last intervention was ETI and Intensive Care Unit (ICU) admission. Of the total study population, CPAP was required in 40%, ETI in 26%, while 15% died. By means of a ROC analysis, a LUS ≥ 25 points was identified as the cut-off point for mortality(AUC 0.81, OR 1.40, 95% CI 1.14 to 1.71; p < 0.001), ETI (AUC 0.83, OR 1.43, 95% CI 1.20 to 1.70; p < 0.001) and HFNC failure (AUC 0.75, OR 1.25, 95% CI 1.12 to 1.41; p < 0.001). Kaplan-Meier survival curves also identified LUS ≥ 25 as a predictor of 90-days mortality (HR 4.16, 95% CI 1.27–13.6) and 30 days ETI as well.ConclusionIn our study, a ≥ 25 point cut-off of the Lung Ultrasound Score was identified as a good outcome prediction factor for 90-days mortality, ETI and HFNC failure in a COVID-19 ARF patients cohort treated in a RICU. Considering that LUS score is easy to calculate, a multicenter study to confirm our findings should be performed.

Prognosis of mechanically ventilated patients with COVID-19 after failure of high-flow nasal cannula: a retrospective cohort study

BackgroundThere is an argument whether the delayed intubation aggravate the respiratory failure in Acute respiratory distress syndrome (ARDS) patients with coronavirus disease 2019 (COVID-19). We aimed to investigate the effect of high-flow nasal cannula (HFNC) failure before mechanical ventilation on clinical outcomes in mechanically ventilated patients with COVID-19.MethodsThis retrospective cohort study included mechanically ventilated patients who were diagnosed with COVID-19 and admitted to the intensive care unit (ICU) between February 2020 and December 2021 at Asan Medical Center. The patients were divided into HFNC failure (HFNC-F) and mechanical ventilation (MV) groups according to the use of HFNC before MV. The primary outcome of this study was to compare the worst values of ventilator parameters from day 1 to day 3 after mechanical ventilation between the two groups.ResultsOverall, 158 mechanically ventilated patients with COVID-19 were included in this study: 107 patients (67.7%) in the HFNC-F group and 51 (32.3%) in the MV group. The two groups had similar profiles of ventilator parameter from day 1 to day 3 after mechanical ventilation, except of dynamic compliance on day 3 (28.38 mL/cmH2O in MV vs. 30.67 mL/H2O in HFNC-F, p = 0.032). In addition, the HFNC-F group (5.6%) had a lower rate of ECMO at 28 days than the MV group (17.6%), even after adjustment (adjusted hazard ratio, 0.30; 95% confidence interval, 0.11–0.83; p = 0.045).ConclusionsAmong mechanically ventilated COVID-19 patients, HFNC failure before mechanical ventilation was not associated with deterioration of respiratory failure.

Can the ROX index predict high-flow nasal cannula failure in children under 2 with lower respiratory tract infection?

This study evaluates the ROX index's accuracy in predicting the success or failure of high-flow nasal cannula (HFNC) therapy in children under 2 years with acute respiratory failure (ARF) from lower respiratory tract infections. From January 2018 to 2021 we conducted this multicenter retrospective cohort study, which included patients aged 2-24 months. We aimed to assess HFNC therapy outcomes as either success or failure. The analysis covered patient demographics, diagnoses, vital signs, and ROX index values at intervals from 0 to 48 h after initiating HFNC. We used bivariate analysis, repeated measures ANOVA, multivariate logistic regression, and the area under the receiver operating characteristic (AUC-ROC) curve for statistical analysis. The study involved 529 patients from six centers, with 198 females (37%) and a median age of 9 months (IQR: 3-15 months). HFNC therapy failed in 38% of cases. We observed significant variability in failure rates across different centers and physicians (p < .001). The ROX index was significantly associated with HFNC outcomes at all time points, showing an increasing trend in success cases over time (p < .001), but not in HFNC failure cases. Its predictive ability is limited, with AUC-ROC values ranging from 0.56 at the start to 0.67 at 48 h. While the ROX index is associated with HFNC outcomes in children under 2 years, its predictive ability is modest, impacted by significant variability among patients, physicians, and centers. These findings emphasize the need for more reliable predictive tools for HFNC therapy in this patient population.

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

IntroductionBronchiolitis is the most common viral lower respiratory tract infection in children under 2 years of age. Respiratory support with high-flow nasal cannula (HFNC) is increasingly used in this patient...

Noninvasive Respiratory Support for Pediatric Critical Asthma: A Multicenter Cohort Study.

Noninvasive respiratory support (NRS) for pediatric critical asthma includes CPAP; bi-level positive airway pressure (BPAP); and heated, humidified, high-flow nasal cannula (HFNC). We used the Virtual Pediatric System database to estimate NRS by prescribing rates for pediatric critical asthma and characterize patient clinical features and in-patient outcomes by the initial NRS device applied. We performed a retrospective cohort study from 125 participating pediatric ICUs among children 2-17 years of age hospitalized for critical asthma and prescribed NRS from 2017 through 2021. The primary outcomes were NRS modality prescribing rates and trends. Secondary outcomes were descriptive and included demographics, comorbidities, severity of illness indices, and NRS failure rates (defined as escalation from the initial NRS modality to invasive ventilation, HFNC to BPAP or CPAP, or CPAP to BPAP). Of the 10,083 encounters studied, the initial NRS modalities prescribed varied widely by hospital center (HFNC: 69.7 ± 29.6%; BPAP: 27.2 ± 7.1%; CPAP: 3.1 ± 5.9%). The mean rates of HFNC use increased from 59.7% in 2017 to 71.9% in 2021 (+2.5%/y). In contrast, BPAP (-1.6%/y) and CPAP (-0.8%/y) utilization declined throughout the study period. Older children who were obese and with a higher Pediatric Risk of Mortality III-Probability of Mortality score were more frequently prescribed BPAP and CPAP compared with HFNC. Those children on HFNC experienced higher noninvasive respiratory support failure rates versus BPAP (7.3% vs 2.4%; P < .001) but a lower subsequent invasive ventilation rate versus BPAP (0.8% vs 2.4%; P < .001). In this multi-center cohort study, we observed that children with critical asthma are increasingly exposed to HFNC compared with BPAP and CPAP. Rates of HFNC failure were greater than those of BPAP failure, but a majority were transitioned to BPAP without subsequent invasive ventilation. The next steps include prospective trials, including practical end points such as patient comfort and optimal delivery of nebulized treatments to distinguish device superiority and suitable NRS utilization.

The correlation between lung ultrasound scores and outcomes of high-flow nasal cannula therapy in infants with severe pneumonia

ObjectiveThe study aimed to explore the effectiveness of bedside lung ultrasound (LUS) combined with the PaO2/FiO2 (P/F) ratio in evaluating the outcomes of high-flow nasal cannula (HFNC) therapy in infants with severe pneumonia.MethodsThis retrospective study analyzed the clinical data of 150 infants diagnosed with severe pneumonia and treated with HFNC therapy at our hospital from January 2021 to December 2021. These patients were divided into two groups based on their treatment outcomes: the HFNC success group (n = 112) and the HFNC failure group (n = 38). LUS was utilized to evaluate the patients’ lung conditions, and blood gas results were recorded for both groups upon admission and after 12 h of HFNC therapy.ResultsAt admission, no significant differences were observed between the two groups in terms of age, gender, respiratory rate, partial pressure of oxygen, and partial pressure of carbon dioxide. However, the P/F ratios at admission and after 12 h of HFNC therapy were significantly lower in the HFNC failure group (193.08 ± 49.14, 228.63 ± 80.17, respectively) compared to the HFNC success group (248.51 ± 64.44, 288.93 ± 57.17, respectively) (p < 0.05). Likewise, LUS scores at admission and after 12 h were significantly higher in the failure group (18.42 ± 5.3, 18.03 ± 5.36, respectively) than in the success group (15.09 ± 4.66, 10.71 ± 3.78, respectively) (p < 0.05). Notably, in the success group, both P/F ratios and LUS scores showed significant improvement after 12 h of HFNC therapy, a trend not observed in the failure group. Multivariate regression analysis indicated that lower P/F ratios and higher LUS scores at admission and after 12 h were predictive of a greater risk of HFNC failure. ROC analysis demonstrated that an LUS score > 20.5 at admission predicted HFNC therapy failure with an AUC of 0.695, a sensitivity of 44.7%, and a specificity of 91.1%. A LUS score > 15.5 after 12 h of HFNC therapy had an AUC of 0.874, with 65.8% sensitivity and 89.3% specificity. An admission P/F ratio < 225.5 predicted HFNC therapy failure with an AUC of 0.739, 60.7% sensitivity, and 71.1% specificity, while a P/F ratio < 256.5 after 12 h of HFNC therapy had an AUC of 0.811, 74.1% sensitivity, and 73.7% specificity.ConclusionDecreased LUS scores and increased P/F ratio demonstrate a strong correlation with successful HFNC treatment outcomes in infants with severe pneumonia. These findings may provide valuable support for clinicians in managing such cases.

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

To identify risk factors of high flow nasal cannula (HFNC) failure at a US pediatric hospital without a co-located ICU. Retrospective cohort study of patients aged 0 to 18 years who were started on HFNC in the emergency department or inpatient unit at a community hospital over a 16-month period. Children with chronic medical conditions were excluded. Outcome was HFNC failure, defined as HFNC need greater than floor limit, noninvasive positive pressure, or mechanical ventilation. In bivariate analysis, we compared demographic and clinical factors between those with and without failure. We included variables in a multivariable model on the basis of statistical significance. We used Poisson regression with robust error variance to calculate the adjusted relative risk (aRR) of failure for each variable. Of 195 children, 51% had HFNC failure. In adjusted analysis, failure was higher in all age groups <12 months as compared with older children. For example, children aged 3 to 5 months had a higher risk of failure compared with patients 12 months or older (aRR 1.85, confidence interval [CI] 1.34-2.54). Patients with an asthma exacerbation had a higher risk of failure (aRR 1.39, CI 1.03-1.88). Patients whose respiratory rate or heart rate did not improve also had a higher risk of failure (aRR 1.73, CI 1.24-2.41; aRR 1.47, CI 1.14-1.90). Patients who were younger, had asthma, and did not have improved respiratory rate or heart rate after HFNC were more likely to experience HFNC failure.

A simple nomogram for predicting failure of high-flow nasal cannula in patients with acute hypoxemic respiratory failure

Objective: To evaluate the predictive efficacy of a nomogram in patients with acute hypoxemic respiratory failure (AHRF) undergoing treatment with a high-flow nasal cannula (HFNC). Methods: We conducted a retrospective observational study of patients with AHRF who received HFNC treatment. Data on complications, vital signs on the first day after enrollment, use of vasoactive drugs, Glasgow Coma Scale scores, and clinical respiratory parameters (respiratory rate, pulse oximetry oxygen saturation, and fraction of inspired oxygen) were meticulously recorded. The risk ratio for HFNC failure was computed using an online calculator. Results: Overall, 62 patients were included, of which 29 (46.77%) experienced HFNC failure. No significant differences were observed in age, sex, body mass index, complications, or sequential organ failure assessment scores between the two groups. However, compared with those who responded positively to HFNC treatment, individuals experiencing HFNC failure demonstrated a significant increase in acute physiology and chronic health evaluation Ⅱ scores [ (15.15±5.01)score vs. (21.00±5.76)score; P<0.001 ]. Furthermore, HFNC treatment failure was associated with significantly higher ICU mortality rates [0 vs. 34.48%(10/29),P<0.01] and in-hospital mortality rates [3.03%(1/33) vs. 37.93%(11/29),P<0.01], as well as a marked prolongation of ICU stay [6(4,10)d vs. 11(6,17)d, P=0.012]. In the failure group, the nomogram-derived risk ratio was 0.80±0.18, which was significantly higher than that in the success group (0.65±0.18; P=0.009). The area under the receiver operating characteristic curve of the nomogram for predicting HFNC failure was 0.76, with a sensitivity of 54.8% and a specificity of 93.6%. Conclusion: The nomogram, along with the online calculator, offers a straightforward and effective means for assessing the risk of treatment failure in patients with AHRF undergoing HFNC therapy.

Respiratory rate‑oxygenation (ROX) index for predicting high-flow nasal cannula failure in patients with and without COVID-19

BackgroundThe predictive value of the respiratory rate‑oxygenation (ROX) index for a high-flow nasal cannula (HFNC) in patients with COVID-19 with acute hypoxemic respiratory failure (AHRF) may differ from patients without COVID-19 with AHRF, but these patients have not yet been compared. We compared the diagnostic accuracy of the ROX index for HFNC failure in patients with AHRF with and without COVID-19 during acute emergency department (ED) visits. MethodsWe performed a retrospective analysis of patients with AHRF treated with an HFNC in an ED between October 2020 and April 2022. The ROX index was calculated at 1, 2, 4, 6, 12, and 24 h after HFNC placement. The primary outcome was the failure of the HFNC, which was defined as the need for subsequent intubation or death within 72 h. A receiver operating characteristic (ROC) curve was used to evaluate discriminative power of the ROX index for HFNC failure. ResultsAmong 448 patients with AHRF treated with an HFNC in an ED, 78 (17.4%) patients were confirmed to have COVID-19. There was no significant difference in the HFNC failure rates between the non-COVID-19 and COVID-19 groups (29.5% vs. 33.3%, p = 0.498). The median ROX index was higher in the non-COVID-19 group than in the COVID-19 group at all time points. The prognostic power of the ROX index for HFNC failure as evaluated by the area under the ROC curve was generally higher in the COVID-19 group (0.73–0.83) than the non-COVID-19 group (0.62–0.75). The timing of the highest prognostic value of the ROX index for HFNC failure was at 4 h for the non-COVID-19 group, whereas in the COVID-19 group, its performance remained consistent from 1 h to 6 h. The optimal cutoff values were 6.48 and 5.79 for the non-COVID-19 and COVID-19 groups, respectively. ConclusionsThe ROX index had an acceptable discriminative power for predicting HFNC failure in patients with AHRF with and without COVID-19 in the ED. However, the higher ROX index thresholds than those in previous publications involving intensive care unit (ICU) patients suggest the need for careful monitoring and establishment of a new threshold for patients admitted outside the ICU.

Performance of the ROX index in predicting high flow nasal cannula failure in COVID-19 patients: a systematic review and meta-analysis

COVID-19 patients with acute hypoxemic respiratory failure (AHRF) benefit from high flow nasal cannula (HFNC) oxygen therapy. However, delays in initiating invasive ventilation after HFNC failure are associated with poorer outcomes. The respiratory oxygenation (ROX) index, combining SpO2/FiO2 and respiratory rate, can predict HFNC failure. This meta-analysis evaluated the optimal ROX index cut-offs in predicting HFNC failure among COVID-19 patients at different measurement timings and clinical settings. Three databases were searched for eligible papers. From each study, we reconstructed the confusion matrices at different cut-offs, fitted linear mixed models to estimate the ROX index distribution function, and derived the area under the summary receiver operator characteristic curve (sAUC) and optimal cut-offs to predict HFNC failure. 24 studies containing 4790 patients were included. Overall sAUC was 0.771 (95% CI: 0.666–0.847) (optimal cut-off: 5.23, sensitivity: 0.732, specificity: 0.690). The cut-off values to achieve 80%, 90% sensitivity, 80%, 90% specificity were 5.70, 6.69, 4.45, 3.37, respectively. We stratified the analysis by ROX measurement time and estimated optimal cut-offs and cut-offs to achieve 80% sensitivity and specificity. For 2–6 h and 6–12 h post-HFNC initiation, we propose the use of 80% specific cut-offs to rule in HFNC failure of < 5.33 and < 3.69, respectively. For 12–24 h post-HFNC initiation, we propose the use of the 80% sensitive cut-off of > 6.07 to rule out HFNC failure. Our analysis confirms the overall utility of the ROX index in risk stratification of COVID-19 patients with AHRF receiving HFNC and provides potentially useful cut-offs for different times from HFNC initiation.

The use of respiratory rate-oxygenation index to predict failure of high-flow nasal cannula in patients with coronavirus disease 2019-associated acute respiratory distress syndrome: A retrospective study.

Patients with mild-to-moderate coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (ARDS) can be treated with a high-flow nasal cannula (HFNC). The use of the respiratory rate-oxygenation (ROX) index, calculated as the ratio of oxygen saturation (SpO2)/fractional oxygen (FiO2) to respiratory rate, in the first few hours after HFNC initiation can help identify patients who fail HFNC therapy later. However, few studies have documented the use of the ROX index during the period of HFNC therapy. Therefore, we aimed to demonstrate the diagnostic performance of the ROX index when calculated throughout the HFNC therapy period and to determine the best cut-off point for predicting HFNC failure. We conducted a retrospective study of patients with COVID-19-associated ARDS who commenced HFNC at the Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Thailand, between April 1 and August 30, 2021. We calculated the ROX index every 4 h throughout the HFNC therapy period and defined HFNC failure as a subsequent endotracheal tube intubation. The performance of the ROX index was analyzed using the area under the receiver operating characteristic curve (AUC). We applied the ROX index ≤ 4.88 to predict HFNC failure and obtained a new ROX cut-off point using Youden's method. In total, 212 patients with COVID-19 treated with HFNC were included in the study. Of these, 81 patients (38.2%) experienced HFNC failure. The ROX index ≤ 4.88 demonstrated a reasonable performance in predicting HFNC failure (AUC, 0.77; 95% confidence interval [CI], 0.72-0.83; p<0.001). However, compared with the original cut-off point of ≤ 4.88, the new ROX index cut-off point of ≤ 5.84 delivered optimal performance (AUC, 0.84; 95% CI, 0.79-0.88; p<0.001), with a significantly better discriminative ability (p = 0.007). In conclusion, a ROX index ≤ 5.84 was found to be optimal for predicting HFNC failure in patients with COVID-19-associated ARDS.