Failure Of High-flow Nasal Cannula Research Articles

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.

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.

ROX index as a predictor of failure of high-flow nasal cannula in infants with bronchiolitis

High-flow nasal cannula (HFNC) is a relatively recent therapy that has been used to treat respiratory failure. Until now, the criterion for failure requiring escalation to other forms of ventilatory support has remained unclear. This study evaluated how the ROX index predicts the success or failure of HFNC in infants with bronchiolitis. A prospective, observational, multicenter study was conducted in 2 pediatric ICUs. The data were collected at 7 moments. Patients were categorized into failure and success groups according to HFNC. A total of 102 infants were included, 18(17.6%) of whom failed HFNC therapy. For the ROX index, significant differences were observed between the failure 5.8(95%CI 4.7–7.1) and success 7.7(95%CI 7.2–8.2) groups (p = 0.005) at the 12 h evaluation. According to the analysis of the performance of the ROX index, the AUC at 12 h was 0.716(95%CI 0.591–0.842; p = 0.016). The best cutoff range for the ROX index at 12 h was 6.50–7.18, with a sensitivity of 42% and a specificity of 66% at the cutoff of 6.50, and a sensitivity of 92% and a specificity of 54% at the cutoff of 7.18. We concluded that the ROX index could be effective at predicting the failure of HFNC therapy in infants with bronchiolitis beginning at 12 h after installation.

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.

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.

ROX index versus HACOR scale in predicting success and failure of high-flow nasal cannula in the emergency department for patients with acute hypoxemic respiratory failure: a prospective observational study

BackgroundHigh-flow nasal cannula has been a promising initial respiratory support measure for patients with acute hypoxemic respiratory failure (AHRF) in the emergency department (ED). However, delayed detection of HFNC failure is associated with increased mortality. The ROX index is a tool that can help predict HFNC success. Nonetheless, its utility in ED patients is limited, and no studies have compared it with the HACOR scale, another tool that may be as accurate in predicting HFNC failure. Therefore, we aimed to compare the prognostic utility of the ROX index and the HACOR scale in emergency AHRF patients.MethodsThis prospective observational study was conducted at the ED of Siriraj Hospital, Thailand, between August 2018 and February 2020. Adult patients with AHRF requiring HFNC in the ED were included. The ROX index and the HACOR scale were measured at 1, 2, and 6 h after HFNC initiation. The primary outcome was HFNC success, defined as no intolerance or escalation towards mechanical ventilation or non-invasive ventilation within 48 h.ResultsA total of 75 patients were enrolled; 52 (69.3%) had a successful treatment. The ROX index was higher in the success group, while the HACOR scale was lower at all timepoints. The ROX index yielded generally higher discrimination capacity based on the area under the receiver operating characteristic curve (AUROC) than the HACOR scale [AUROC at 1, 2, and 6 h = 0.815, 0.784, 0.853 for ROX in predicting HFNC success and 0.733, 0.690, and 0.764 for HACOR in predicting HFNC failure]. The ROX index measured at 6 h at the cut-point of 4.88 had 92.98% sensitivity, 61.11% specificity, 88.33% positive predictive value, and 73.33% negative predictive value with a diagnostic accuracy of 85.33%.ConclusionThe ROX index had superior prognostic utility in predicting HFNC outcome (success/failure) compared to the HACOR scale in patients with AHRF in the ED setting. Moreover, it is less complex and more efficient to be employed at bedside. Therefore, the ROX index is a more appropriate tool to guide further management and potential escalation therapy for AHRF patients with HFNC therapy initiated in the ED.

Prediction of noninvasive ventilation failure using the ROX index in patients with de novo acute respiratory failure

BackgroundThe ratio of SpO2/FiO2 to respiratory rate (ROX) index is commonly used to predict the failure of high-flow nasal cannula. However, its predictive power for noninvasive ventilation (NIV) failure is unclear.MethodsThis was a secondary analysis of a multicenter prospective observational study, intended to update risk scoring. Patients with de novo acute respiratory failure were enrolled, but hypercapnic patients were excluded. The ROX index was calculated before treatment and after 1–2, 12, and 24 h NIV. Differences in predictive power for NIV failure using the ROX index, PaO2/FiO2, and PaO2/FiO2/respiratory rate were tested.ResultsA total of 1286 patients with de novo acute respiratory failure were enrolled. Of these, 568 (44%) experienced NIV failure. Patients with NIV failure had a lower ROX index than those with NIV success. The rates of NIV failure were 92.3%, 70.5%, 55.3%, 41.1%, 35.1%, and 29.5% in patients with ROX index values calculated before NIV of ≤ 2, 2–4, 4–6, 6–8, 8–10, and > 10, respectively. Similar results were found when the ROX index was assessed after 1–2, 12, and 24 h NIV. The area under the receiver operating characteristics curve was 0.64 (95% CI 0.61–0.67) when the ROX index was used to predict NIV failure before NIV. It increased to 0.71 (95% CI 0.68–0.74), 0.74 (0.71–0.77), and 0.77 (0.74–0.80) after 1–2, 12, and 24 h NIV, respectively. The predictive power for NIV failure was similar for the ROX index and for the PaO2/FiO2. Likewise, no difference was found between the ROX index and the PaO2/FiO2/respiratory rate, except at the time point of 1–2 h NIV.ConclusionsThe ROX index has moderate predictive power for NIV failure in patients with de novo acute respiratory failure.

Predictive factors for high-flow nasal cannula failure in acute hypoxemic respiratory failure in an intensive care unit.

Background and Objective:High-flow nasal cannula (HFNC), a relatively new technique in acute hypoxemic respiratory failure (AHRF), is gaining popularity in intensive care units (ICUs). Our study aims to identify the predictive factors for failure of HFNC.Materials and Methods:This is a 5-year retrospective cohort study in patients with AHRF using HFNC in an ICU of a regional hospital in Hong Kong. The primary outcome is to identify the predictive factors for failure of HFNC which is defined as escalation of treatment to noninvasive ventilation, mechanical ventilation, extracorporeal membrane oxygenation, or death.Results:Of the 124 ICU patients with AHRF, 69 (55.65%) failed in the use of HFNC. The patients failing HFNC had higher Acute physiology and Chronic Health Evaluation IV scores, lower Glasgow Coma Scale scores, lower platelet counts and serum sodium levels upon ICU admission, and higher pH on day of HFNC commencement. They had higher respiratory rates before HFNC and higher heart rates before and 1 h after HFNC. The respiratory rate-oxygenation (ROX) index which is defined as a ratio of SpO2/FiO2 to respiratory rate was significantly lower in the failure group 1 h and 12 h after HFNC. By multivariate binary logistic regression, failure of HFNC is associated with lower ROX index at 12 h after HFNC.Conclusion:ROX index at 12 h serves as a valuable tool to monitor the responsiveness to HFNC treatment. Close monitoring is required to identify patient failing using HFNC.

Comparison of high flow oxygen therapy in children with respiratory distress due to bronchiolitis and pneumonia

Background: Respiratory support through high flow nasal cannula (HFNC) therapy has emerged as a new method to provide respiratory support with bronchiolitis. Aim was to study outcome of HFNC therapy in children with bronchiolitis and pneumonia.Methods: The study was a prospective observational study involving children admitted to pediatric intensive care unit with respiratory distress (RD) in the age group of 1 month to 6 years over a period of 3 months (February 2017 till April 2017). Severity was assessed by clinical respiratory score (CRS). Children with RD were initiated with high flow nasal cannula. During treatment various parameters including CRS were documented at baseline and at 15 min and then hourly in a carefully designed performa. The primary outcome was failure of HFNC and need for ventilation.Results: Sixty children were included in the study of which 22 (37%) were in the bronchiolitis group and 38 (63%) were in the pneumonia group. 38 children presented with severe RD and 19 children with moderate RD. There was significant decrease in heart rate (HR) (20%), respiratory rate (RR) (20%) and in CRS within 1 hour of HFNC with a clinical stabilization within 24 hours in 16 cases (27%), 24-48 hours in 35 cases (58%) and &gt;48 hours in 5 (8%) cases. Therapy was successful in 55 (92%), and failed in 5 (8%).Conclusions: HFNC has better outcome in children with RD due to acute bronchiolitis when compared to pneumonia. HFNC can be safely commenced in RD in critically ill child with monitoring.

Late Failure of High-Flow Nasal Cannula May Be Associated with High Mortality in COVID-19 Patients: A Multicenter Retrospective Study in the Republic of Korea.

The aim of this study was to determine whether the late failure of high-flow nasal cannula (HFNC) is associated with mortality in patients with coronavirus disease 2019 (COVID-19). This multicenter study included seven university-affiliated hospitals in the Republic of Korea. We collected the data of patients hospitalized with COVID-19 between 10 February 2020 and 28 February 2021. Failure of HFNC was defined as the need for mechanical ventilation despite HFNC application. According to the time of intubation, HFNC failure was divided into early failure (within 48 h) and late failure (after 48 h). During the study period, 157 patients received HFNC and 133 were eligible. Among them, 70 received mechanical ventilation. The median time from HFNC initiation to intubation of the early failure group was 4.1 h (interquartile range [IQR]: 1.1–13.5 h), and that of the late failure group was 70.9 h (IQR: 54.4–145.4 h). Although the ratio of pulse oximetry/fraction of inspired oxygen (ROX index) within 24 h of HFNC initiation tended to be lower in the early failure group than in the late failure group, the ROX index before two hours of intubation was significantly lower in the late failure group (odds ratio [OR], 5.74 [IQR: 4.58–6.98] vs. 4.80 [IQR: 3.67–5.97], p = 0.040). The late failure of HFNC may be associated with high mortality in COVID-19 patients with acute respiratory failure.

The COVID-19 pandemic: the effect on airway Management in non-COVID emergency patients

BackgroundDuring the COVID-19 outbreak, healthcare providers might have avoided droplet/aerosol-generating procedures, such as non-invasive ventilation (NIV) and high-flow nasal cannula (HFNC) due to the concern of themselves being infected. We hypothesized that this change of practice could have also occurred to other non-COVID-infected patients in the Emergency Department (ED).MethodsA retrospective analytic study was conducted in the ED of Siriraj Hospital, Bangkok, Thailand, including adult patients presenting with signs and symptoms of respiratory distress between 1 March and 30 April 2020 (the COVID period). A comparison group using the same inclusion criteria was retrieved from 1 March to 30 April 2019 (the pre-COVID period). The primary outcome was rate of NIV and HFNC use. The secondary outcomes were rate of intubation, failure of NIV and HFNC, complications, and mortality.ResultsA total of 360 and 333 patients were included during the pre-COVID and COVID periods, respectively. After adjusting for baseline differences, patients in the COVID period were less likely to receive either NIV or HFNC than the pre-COVID period (adjusted OR 0.52 [95%CI 0.29–0.92]). Overall, intubation rate was similar between the two study periods. However, patients in respiratory distress with pulmonary edema had a relatively higher intubation rate in the COVID period. There were higher failure rates of NIV and HFNC, more infectious complications, and a higher rate of mortality in the pre-COVID period.ConclusionDuring the COVID-19 pandemic, the overall usage of NIV and HFNC in emergency non-COVID patients decreased. Although not affecting the overall intubation rate, this change of practice could have affected some groups of patients. Therefore, treatment decisions based on a balance between the benefits to the patients and the safety of healthcare providers should be made.

Efficacy of High-Flow Nasal Cannula Oxygen Therapy in Patients with Mild Hypercapnia

ObjectivesTo investigate the indications of high-flow nasal cannula (HFNC) oxygen therapy among patients with mild hypercapnia and to explore the predictors of intubation when HFNC fails.MethodsThis retrospective study was conducted based on the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Adult patients with mild hypercapnia (45 < PaCO2 ≤ 60 mmHg) received either HFNC or non-invasive ventilation (NIV) oxygen therapy. Propensity score matching (PSM) was implemented to increase between-group comparability. The Kaplan–Meier method was used to estimate overall survival and cumulative intubation rates, while 28-day mortality and 48-h and 28-day intubation rates were compared using the Chi-squared test. The predictive performances of HR/SpO2 and the ROX index (the ratio of SpO2/FiO2 to respiratory rate) at 4 h were assessed regarding HFNC failure, which was determined if intubation was given within 48 h after the initiation of oxygen therapy. The area under the receiver operating characteristic curve (AUC) for HR/SpO2 and the ROX index were calculated and compared.ResultsA total of 524,520 inpatient hospitalization records were screened, 106 patients in HFNC group and 106 patients in NIV group were successfully matched. No significant difference in 48-h intubation rate between the HFNC group (the treatment group) and the NIV group (the control group) (14.2% vs. 8.5%, p = 0.278); patients receiving HFNC had higher 28-day intubation rate (26.4% vs. 14.2%, p = 0.029), higher 28-day mortality (17.9% vs. 8.5%, p = 0.043), and longer ICU length of stay (4.4 vs. 3.3 days, p = 0.019), compared to those of NIV group. The AUC of HR/SpO2 at 4 h after the initiation of HFNC yielded around 0.660 for predicting 48-h intubation, greater than that of the ROX index with an AUC of 0.589 (p < 0.01).ConclusionPatients with impending respiratory failure had lower intubation rate, shorter ICU length of stay, and lower mortality when treated mild hypercapnia with NIV over HFNC. As opposed to the ROX index, a modest, yet improved predictive performance is demonstrated using HR/SpO2 in predicting the failure of HFNC among these patients.

High-Flow Nasal Cannula for Patients with Acute Respiratory Failure Treated in a General Medical Ward: A Prospective Cohort Study

Background: Hypoxemia and the need for oxygen administration are frequent causes of hospital admission. High-flow nasal cannula (HFNC) delivers heated humidified high-flow gas at an adjustable inspired oxygen fraction via a large-bore nasal cannula and provide specific physiological benefits. The efficacy of HFNC has been investigated in the intensive care unit but data in other care settings are scarce, especially in low- and middle-income countries. Objective: To describe the safety and associated clinical outcomes of HFNC used in patients admitted to general medical wards. Materials and Methods: The present study was a prospective cohort study that enrolled adult patients with acute respiratory failure and no other major organ failures admitted to the general medical wards at Siriraj Hospital in Bangkok and treated with HFNC. Enrolled subjects were managed by a multidisciplinary care team trained in HFNC usage. The primary outcome was to determine the rate of HFNC failure, defined as the subsequent need for endotracheal intubation, non-invasive ventilation (NIV), reintubation, or death within 48 hours. Secondary outcomes included determining the in-hospital mortality, 28-day mortality, and the factors associated with HFNC failure. Results: Seventy-one subjects were enrolled. In these patients, acute de novo hypoxemic respiratory failure was the most common indication for HFNC (42.3%), followed by prophylaxis after extubation (38.0%), and cardiogenic pulmonary edema (19.7%). The overall rate of HFNC failure was 25.4%. The overall in-hospital and 28-day mortality rates were 14.1% and 21.1%, respectively. The only factor associated with HFNC failure was the respiratory rate at day 1. Conclusion: The use of HFNC in general medical wards is feasible, but a 25% rate of failure within 48 hours can be expected. A higher respiratory rate at day 1 is associated with the failure of HFNC. Keywords: Acute respiratory failure; General medical ward; High-flow oxygen therapy; Outcomes; Safety

Failure of non-invasive respiratory support after 6 hours from initiation is associated with ICU mortality.

A previous study has shown that late failure (> 48 hours) of high-flow nasal cannula (HFNC) was associated with intensive care unit (ICU) mortality. The aim of this study was to investigate whether failure of non-invasive respiratory support, including HFNC and non-invasive positive pressure ventilation (NPPV), was also associated with the risk of mortality even if it occurs in the earlier phase. We retrospectively analyzed 59 intubated patients for acute respiratory failure due to lung diseases between April 2014 and June 2018. We divided the patients into 2 groups according to the time from starting non-invasive ventilatory support until their intubation: ≤ 6 hours failure and > 6 hours failure group. We evaluated the differences in the ICU mortality between these two groups. The multivariate logistic regression analysis showed the highest mortality in the > 6 hours failure group as compared to the ≤ 6 hours failure group, with a statistically significant difference (p < 0.01). It was also associated with a statistically significant increased 30-day mortality and decreased ventilator weaning rate. The ICU mortality in patients with acute respiratory failure caused by lung diseases was increased if the time until failure of HFNC and NPPV was more than 6 hours.

High-Flow Nasal Cannula Therapy in COVID-19: Using the ROX Index to Predict Success.

Optimal timing of mechanical ventilation in COVID-19 is uncertain. We sought to evaluate outcomes of delayed intubation and examine the ROX index (ie, [[Formula: see text]]/breathing frequency) to predict weaning from high-flow nasal cannula (HFNC) in patients with COVID-19. We performed a multicenter, retrospective, observational cohort study of subjects with respiratory failure due to COVID-19 and managed with HFNC. The ROX index was applied to predict HFNC success. Subjects that failed HFNC were divided into early HFNC failure (≤ 48 h of HFNC therapy prior to mechanical ventilation) and late failure (> 48 h). Standard statistical comparisons and regression analyses were used to compare overall hospital mortality and secondary end points, including time-specific mortality, need for extracorporeal membrane oxygenation, and ICU length of stay between early and late failure groups. 272 subjects with COVID-19 were managed with HFNC. One hundred sixty-four (60.3%) were successfully weaned from HFNC, and 111 (67.7%) of those weaned were managed solely in non-ICU settings. ROX index >3.0 at 2, 6, and 12 hours after initiation of HFNC was 85.3% sensitive for identifying subsequent HFNC success. One hundred eight subjects were intubated for failure of HFNC (61 early failures and 47 late failures). Mortality after HFNC failure was high (45.4%). There was no statistical difference in hospital mortality (39.3% vs 53.2%, P = .18) or any of the secondary end points between early and late HFNC failure groups. This remained true even when adjusted for covariates. In this retrospective review, HFNC was a viable strategy and mechanical ventilation was unecessary in the majority of subjects. In the minority that progressed to mechanical ventilation, duration of HFNC did not differentiate subjects with worse clinical outcomes. The ROX index was sensitive for the identification of subjects successfully weaned from HFNC. Prospective studies in COVID-19 are warranted to confirm these findings and to optimize patient selection for use of HFNC in this disease.

Factors associated with treatment failure of high-flow nasal cannula among children with bronchiolitis: a single-centre retrospective study.

Bronchiolitis is the most common viral lower respiratory tract infection in children under age 2 for which high-flow nasal cannula (HFNC) is increasingly used. Understanding factors associated with HFNC failure is important to identify patients at risk for respiratory deterioration. The objective of this study was to evaluate patient characteristics associated with HFNC failure in bronchiolitis. A retrospective review of patients aged 0 to 24 months, with bronchiolitis who received HFNC within a single tertiary paediatric intensive care unit, between January 2014 and December 2018 was conducted. HFNC treatment failure was defined as escalation to non-invasive positive pressure or invasive mechanical ventilation. Multivariable regression analysis was used to identify demographic, clinical, and biochemical parameters associated with HFNC failure. Two hundred eight patients met inclusion criteria, of which 61 (29.33%) failed HFNC. Risk factors for HFNC failure included younger age (odds ratio [OR] 1.12; 95% confidence interval [CI] 1.03, 1.23; P=0.011) and a Modified Tal score greater than 5 at 4 hours of HFNC therapy (OR 2.81; 95% CI 1.04, 7.64; P=0.042). Duration of HFNC in hours was protective (OR 0.94; 95% CI 0.92, 0.96; P<0.001), such that deterioration is less likely once patients have remained stable on HFNC for a prolonged time. This is the first study exploring predictors of HFNC failure among Canadian children with bronchiolitis. Patient age, HFNC duration, and Modified Tal score were associated with HFNC failure. These factors should be considered when initiating HFNC for bronchiolitis to identify patients at risk for deterioration.

Factors Associated With Failure of High-Flow Nasal Cannula.

The use of high-flow nasal cannula (HFNC) is rapidly increasing without clear indications, creating the potential for overuse or misuse and the accompanying risk of adverse events. The purpose of this study was to determine the factors associated with HFNC failure by examining the current clinical practice of HFNC. From July 1, 2017, to June 30, 2018, in 5 university-affiliated hospitals in the Republic of Korea, a total of 1,161 admitted adult subjects who had HFNC administered were retrospectively enrolled and their medical records were reviewed. Pulmonary diseases including pneumonia (n = 757, 65.2%) were the most common reason for use of HFNC. Subjects with do-not-resuscitate (DNR) or do-not-intubate (DNI) orders comprised 33.8% of the study population (n = 392); 563 subjects (48.5%) were escalated directly to HFNC from low-flow devices without applying reservoir or other high-flow devices. In the non-DNR/DNI subjects, arterial blood gas was not monitored in 15.2% and 14.8% of subjects before and after HFNC application, respectively, and it was not monitored in 28.0% just before HFNC weaning. The HFNC failure rate was 27.0% in non-DNR/DNI subjects, and the HFNC failure was significantly associated with the decision by residents to apply HFNC (odds ratio [OR] 2.03, 95% CI 1.29-3.18, P = .002), high breathing frequency (OR 1.07, 95% CI 1.04-1.10, P < .001) ≤ 6 h before HFNC application, low [Formula: see text] (OR 0.92, 95% CI 0.89-0.95, P < .001) ≤ 6 h before HFNC application, low [Formula: see text] (OR 0.95, 95% CI 0.93-0.98, P < .001) ≤ 6 h before HFNC application, and the ratio of [Formula: see text]/[Formula: see text] to breathing frequency (ROX index) ≤ 6 h after HFNC application (OR 0.88, 95% CI 0.84-0.92, P < .001). HFNC was practiced without applying reservoir or other high-flow devices before application and without appropriate arterial blood gas monitoring during HFNC therapy. HFNC failure was significantly associated with the decision by the resident to use HFNC, breathing frequency, [Formula: see text], and [Formula: see text] ≤ 6 h before HFNC application, and with the ROX index ≤ 6 h after HFNC application.

High flow nasal cannula in patients treated inside and outside the pediatric intensive care units: pending challenges

High Flow Nasal Cannula (HFNC) is a non-invasive oxygen therapy system it consists in the administration of gas flows, mixture of air and oxygen (O2 ), which exceed the patient’s ventilatory demands and also it is a friendly system, which allows its use outside of critical units. Objective: To collect and analyse the available literature in relation to the definition and clinical parameters that predict the failure of HFNC therapy, in hospitalized pediatric patients inside and outside the ICU, in order to provide knowledge to clinicians to optimize the management of this device, facilitate the administration of the resources and finally, improve the pediatric patients outcomes by identifying the clinical predictors of HFNC failure. Conclusion: There is no consensus regarding the definition of failure of HFNC, which makes it difficult to interpretate the results of the studies and, therefore, its translation into clinical practice. On the other hand, although predictive factors of failure have been identified, in most studies, are restricted to demographic characteristics, comorbidities, severity indexes and/or require the taking of arterial blood tests, therefore their applicability outside of the Pediatric Intensive Care Unit (PICU), is limited. Regarding the identification of clinical parameters, some of the studies mentioned their correlation with failure, but during the administration of the therapy and not previously. This situation makes the early characterization of patients who require HFNC more difficult, and therefore, the individualized decisions that could eventually improve economical and clinical outcomes of our pediatric patients.

Predictors of success of high flow nasal cannula (HFNC) therapy in children with respiratory distress in pediatric intensive care unit

Objective: To identify clinical and laboratory variables that predict success of High Flow Nasal Canula (HFNC) therapy in children presenting to Pediatric Intensive Care Unit (PICU) with respiratory distress of varied etiology. Methods: This was a prospective observational study conducted in PICU of St John’s medical college, Bengaluru over a period of one year from May 2016 to April 2017. All children 1 month to 2 years presenting with moderate/severe respiratory distress of varied etiology were included for the study. The standard exclusion criteria of noninvasive ventilation were used. They were started on HFNC and clinical and laboratory variables were monitored at regular intervals. The participants were categorized as responders and non-responders (defined by need for escalation of respiratory support to invasive ventilation while on HFNC therapy). Results: One hundred fourteen childrens participated in the study, 99 of them responded and 15 were non-responders. Fifty nine had pneumonia(51.7%), 14 had WALRI (12.2%),13 had bronchiolitis (11.4%), 12 had post extubation respiratory distress(10.5%), 8 had fluid overload with respiratory distress(7%), 4 had upper air way obstruction (1.7% ), 4 had respiratory distress due to other causes. No differences were noted between these two groups for age, sex, weight, comorbid conditions. Decreasing heart rate, decrease in the mean respiratory rate and improving distress score at the end of 1 hour and 6 hours strongly correlated with response to therapy. The PRISM III scores were significantly higher (p =0.004) in non-responders. Respiratory distress due to pneumonia as underlying etiology was another predictor of failure of HFNC (p=0.009). No differences were noted in arterial blood gas parameters between these two groups, however paO2 among responders was significantly higher compared to non-responders at the initiation of HFNC and at 1 hour. Conclusion: Improving trends of clinical vital signs like heart rate, respiratory rate and RDS while on HFNC therapy are the key to success. Majority of children who failed HFNC had pneumonia as the underlying etiology of respiratory distress.