High-flow Nasal Cannula Oxygen Research Articles

What if youth is not enough? Acute coronary syndrome in young patients

Abstract Funding Acknowledgements None. Background Acute Coronary Syndromes (ACS) are the leading cause of mortality in Spain. Further research is needed in order to know risk factors and outcomes in young patients so that medicians could optimize their management and prevention. Purpose Identifying risk factors, clinical characteristics and short-term outcomes in Acute Coronary Syndrome in patients aged 40 and under. Methods A retrospective analysis of patients under 40 years of age who were admitted for ACS, out of 3,859 ACS admissions in Cardiology Intensive Care Unit (CICU) in our hospital between 2012 and 2022. Results 67 patients (1.73%) were included, most of them were males (83.6%). Baseline characteristics are summarized in Table 1. 77.6% had hypertension (HTA), 22.4% had diabetes (DM) and 34.3% had dyslipidemia (DLP). 79.1% were smokers, 9.1% had a history of alcoholism and 29.9% were cocaine users. None of them had a history of stroke, atrial fibrillation (AF). Only 3% had ischemic heart disease. 68.7% of them were ST-elevation myocardial infarction (STEMI) and inferior STEMI was the most common (38.7%). In anterior STEMI (22 patients), 15 had a severe lesion in the mid-left anterior descending artery (LAD), and 6 in the left main stem (LM). Single-vessel disease was the most common (70.8%), with 3-vessel disease in 4.6%. 75.8% received percutaneous coronary intervention (PCI), and 3% underwent bypass surgery. During admission, 10.5% progressed to Killip class III-IV. The ICU mortality was 1.5%. 9% received vasoactive drugs and 4.5% were intubated. Non-invasive ventilation was used in 3% and high-flow nasal cannula oxygen therapy in 5.3%. 3% received intra-aortic balloon pump support and 1.5% underwent dialysis or ultrafiltration. 4.5% received an implantable cardioverter-defibrillator (ICD), although none of them developed bundle branch block or atrioventricular node block, nor AF. After discharge, 11.1% had recurrent ACS, and up to 5.6% underwent PCI again, with a mortality rate of 11.8%. Conclusion Approximately 2% of ACS occur in people younger than 40 years of age. Substance abuse (smoking, cocaine and alcoholism) becomes more prevalent in this group. Prevalence of comorbidities (such as diabetes and nephropathy) are lower, making them less prone to short-term heart failure. However, they are more susceptible to recurrent ischemic events. There is a high incidence of inferior STEMI and LM-STEMI. For these reasons, medicians may need to find out a substance abuse in this group and further research into other risk factors, such as coronary disease family history.Basal characteristicsClinical evolution of patients

Retrospective evaluation of the respiratory rate-oxygenation index to predict the outcome of high-flow nasal cannula oxygen therapy in dogs (2018-2021): 81 cases.

To evaluate the respiratory rate-oxygenation index (ROX), modified ROX index (ROX-HR), and the ratio of pulse oximetry saturation (Spo2) to Fio2 (SF) to determine if these indices over time are predictive of outcome in dogs treated with high-flow nasal cannula oxygen therapy (HFNC). Retrospective study. Two university teaching hospitals. Eighty-one client-owned dogs treated with HFNC for hypoxemic respiratory failure. None. The ROX was defined as the SF divided by the respiratory rate (RR), and the ROX-HR was defined as the ROX divided by the heart rate multiplied by 100. The overall success rate of HFNC was 44% (n=36/81). Dogs weaned from HFNC had a significantly higher ROX (P<0.0001) at 1-3, 5-10, 12, and 15hours than dogs that failed HFNC. Both the ROX and SF showed excellent discriminatory power in predicting HFNC failure at 6hours, with an area under receiver operating curve of 0.85 (95% confidence interval: 0.72-0.99; P<0.002) and 0.86 (95% confidence interval: 0.73-0.99; P<0.001), respectively. The optimal cutoff values for predicting HFNC failure at 6hours were a ROX ≤3.68 (sensitivity 72%, specificity 92%) and an SF ≤143 (sensitivity 79%, specificity 93%). These results suggest that similar to people, the ROX and SF are useful predictors of HFNC failure. These indices are easy to measure at the bedside and may have clinical use. Future prospective studies are warranted to confirm the findings and to optimize cutoff values in a larger population of dogs undergoing HFNC.

Effects of high-flow nasal cannula oxygen therapy in bronchiectasis and hypercapnia: a retrospective observational study

BackgroundThe effectiveness of high-flow nasal cannula (HFNC) therapy in patients with bronchiectasis experiencing hypercapnia remains unclear. Our aim was to retrospectively analyze the short-term outcomes of HFNC therapy in such patients, and to further explore the predictors of HFNC treatment failure in this particular patient population.MethodsA retrospective review was conducted on patients with bronchiectasis who received HFNC (n = 70) for hypercapnia (arterial partial pressure of carbon dioxide, PaCO2 ≥ 45 mmHg) between September 2019 and September 2023.ResultsIn the study population, 30% of patients presented with acidemia (arterial pH < 7.35) at baseline. Within 24 h of HFNC treatment, there was a significant reduction in PaCO2 levels by a mean of 4.0 ± 12.7 mmHg (95% CI -7.0 to -1.0 mmHg). Concurrently, arterial pH showed a statistically significant increase with a mean change of 0.03 ± 0.06 (95% CI 0.01 to 0.04). The overall hospital mortality rate in our study was 17.5%. The median length of hospital stay was 11.0 days (interquartile range [IQR] 8.0 to 16.0 days). Sub-analysis revealed no statistically significant differences in hospital mortality (19.0% vs. 20.4%, p = 0.896), length of hospital stay (median 14.0 days [IQR 9.0 to 18.0 days] vs. 10.0 days [IQR 7.0 to 16.0 days], p = 0.117) and duration of HFNC application (median 5.0 days [IQR 2.0 to 8.5 days] vs. 6.0 days [IQR 4.9 to 9.5 days], p = 0.076) between the acidemia group and the non-acidemia group (arterial pH ≥ 7.35). However, more patients in the non-acidemia group had do-not-intubate orders. The overall treatment failure rate for HFNC was 28.6%. Logistic regression analysis identified the APACHE II score (OR 1.24 per point) as the independent predictor of HFNC failure.ConclusionsIn patients with bronchiectasis and hypercapnia, HFNC as an initial respiratory support can effectively reduce PaCO2 level within 24 h of treatment. A high APACHE II score has emerged as a prognostic indicator for HFNC treatment failure. These observations highlight randomized controlled trials to meticulously evaluate the efficacy of HFNC in this specific population.

High-Flow Nasal Cannula Oxygen Therapy versus Non-Invasive Ventilation in patients at very high risk for extubating failure: A systematic review of randomized controlled trials.

Mechanical ventilation is commonly used for managing respiratory failure in chronic obstructive pulmonary disease (COPD) patients, but weaning patients off ventilator support can be challenging and associated with complications. While many patients respond well to Non-invasive ventilation (NIV), a significant proportion may not respond as favourably. We aimed to assess whether high-flow nasal cannula (HFNC) is equally effective as NIV in reducing extubation failure among previously intubated COPD patients. This systematic review was carried out in line with PRISMA guidelines We searched PubMed, Scopus, Web of Science, and Cochrane library from inception until February 15, 2023. Randomized Clinical Trials (RCTs) of adults at high risk for extubating failure were included. We examined the use of HFNC as the intervention and NIV as the comparator. Our outcome of interest included, reintubation rate, length of hospital or intensive care unit (ICU) stay, adverse events, and time to reintubation. The Cochrane risk-of-bias tool was used for randomized trials to assess risk of bias. We identified 348 citations, 11 of which were included, representing 2,666 patients. The trials indicate that HFNC is comparable to NIV in preventing reintubation after extubating in COPD patients. In comparison to NIV, HFNC also produced improved tolerance, comfort, and less complications such as airway care interventions. NIV with active humification may be more effective that HFNC in avoiding reintubation in patients who are at extremely high risk for extubating failure. The inconclusive nature of emerging evidence highlights the need for additional studies to establish the efficacy and suitability of HFNC as an alternative to NIV for previously intubated COPD patients. Clinicians should consider the available options and individualize their approach based on patient characteristics. Future research should focus on addressing these gaps in knowledge to guide clinical decision-making and optimize outcomes for this patient population.

Airway and anesthesia management in tracheoesophageal fistula closure implantation: a single-centre retrospective study

ObjectiveTo review and analyze the airway and anesthesia management methods for patients who underwent endoscopic closure of tracheoesophageal fistula (TEF) and to summarize the experience of intraoperative airway management.MethodWe searched the anesthesia information system of the First Affiliated Hospital of Nanjing Medical University for anesthesia cases of TEF from July 2020 to July 2023 and obtained a total of 34 anesthesia records for endoscopic TEF occlusion. The intraoperative airway management methods and vital signs were recorded, and the patients’ disease course and follow-up records were analyzed and summarized.ResultsThe airway management strategies used for TEF occlusion patients included nasal catheter oxygen (NCO, n = 5), high-flow nasal cannula oxygen therapy (HFNC, n = 4) and tracheal intubation (TI, n = 25). The patients who underwent tracheal intubation with an inner diameter of 5.5 mm had stable hemodynamics and oxygenation status during surgery, while intravenous anesthesia without intubation could not effectively inhibit the stress response caused by occluder implantation, which could easily cause hemodynamic fluctuations, hypoxemia, and carbon dioxide accumulation. Compared with those in the TI group, the NCO group and the HFNC group had significantly longer surgical times, and the satisfaction score of the endoscopists was significantly lower. In addition, two patients in the NCO group experienced postoperative hypoxemia.ConclusionDuring the anesthesia process for TEF occlusions, a tracheal catheter with an inner diameter of 5.5 mm can provide a safe and effective airway management method.

High-flow nasal oxygen in infants and children for early respiratory management of pneumonia-induced acute hypoxemic respiratory failure: the CENTURI randomized clinical trial

ObjectiveTo compare the effectiveness of early high-flow nasal cannula (HFNC) and low-flow oxygen support (LFOS) in children under 5 years with acute hypoxemic respiratory failure (AHRF) due to severe community-acquired pneumonia in low-middle-income countries.MethodsAn open-label randomized clinical trial enrolled children aged 2–59 months with AHRF due to severe community-acquired pneumonia and randomized into HFNC and LFOS. In the LFOS group, the patient received cold wall oxygen humidified by bubbling through sterile water administered through simple nasal prongs at a fixed flow rate of 2 L/min. In the HFNC group, the patient received humidified, heated (37 °C), high-flow oxygen at a flow rate assigned based on weight range, with a titratable oxygen fraction. The primary outcome was treatment failure in 72 h (escalating the respiratory support method using any modality other than primary intervention).ResultsData was analyzed intention-to-treat (HFNC = 124; LFOS = 120). Median (IQR) age was 12 (6–20) and 11 (6–27) months, respectively. Treatment failure occurred in a significantly lower proportion in the HFNC group (7.3%, n = 9/124) as compared to the LFOS group (20%, n = 24/120) (relative risk = 0.36, 95% CI 0.18 to 0.75; p = 0.004; adjusted hazard ratio 0.34, 95% CI 0.16 to 0.73; p = 0.006). The intubation rate was significantly lower in the HFNC group (7.3%, n = 9/124 vs. 16.7%, n = 20/120; relative risk = 0.44, 95% CI 0.21 to 0.92, p = 0.023). There were no significant differences noted in other secondary outcomes. No mortality occurred.ConclusionHigh-flow nasal cannula oxygen therapy used as early respiratory support in children under 5 years with acute hypoxemic respiratory failure due to severe community-acquired pneumonia was associated with significantly lower treatment failure compared with standard low-flow oxygen support.Trial registration CTRI/2016/04/006788. Registered 01 April 2016, https://ctri.nic.in/Clinicaltrials/advsearch.php.

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.

Risk factors for intubation and mortality in patients treated with high flow nasal cannula due to COVID-19 infection. Survival Analysis Study in a Northern Mexican Population.

COVID-19-related acute hypoxic respiratory failure patients often use high-flow nasal cannula (HFNO) oxygen therapy. COVID-19 HFNO intubation and mortality risk factors are understudied in the Mexican population, so the aim was to study them. This retrospective study searched electronic medical records from March 2020 to June 2022 for patients with COVID-19 who required hospitalization and HFNO. Descriptive statistics, a survival curve analysis, and Cox proportional hazard models were used to determine predictor factors for intubation and mortality in patients with HFNO and COVID-19, respectively. A total of 134 patients received HFNO treatment. Ninety-one (67.9%) were men with a mean (SD) age of 54.5 (17.9) years. Common medical history included obesity (n = 89, 66.4%) with a Body Mass Index (BMI) mean (SD) of 31.8 (5.9), hypertension (n = 67, 50.0%), type 2 diabetes (n = 55, 41.0%), and dyslipidemias (n = 43, 32.1%). The variables associated with a greater risk of requiring intubation after high-flow therapy were age (HR = 1.018, 95% CI 1.003-1.034, p = 0.022) and BMI (HR = 1.071, 95% CI 1.024-1.120, p = 0.003). No variables were associated with lower risk. Increased mortality was associated with increasing age (HR = 1.151, 95% CI 1.102-1.201, p = <0.001), hypertension (HR = 4.092, 95% CI 1.369-12.236, p = 0.012), and dyslipidemia (HR = 3.954, 95% CI 1.395-11.209, p = 0.010). Patients with type 2 diabetes had a lower risk of mortality (HR = 0.235, 95% CI 0.080-0.688, p = 0.008). A higher age and BMI were associated with an increased risk of intubation in patients with HFNO and COVID-19. Hypertension and dyslipidemias were associated with a higher risk of mortality.

Effectiveness of Helmet-CPAP in mild to moderate coronavirus type 2 hypoxemia: An observational study

ObjectiveTo determine the relative effectiveness of Helmet-CPAP (H_CPAP) with respect to high-flow nasal cannula oxygen therapy (HFNO) in avoiding greater need for intubation or mortality in a medium complexity hospital in Chile during the year 2021. DesignCohort analytical study, single center. SettingUnits other than intensive care units. PatientsRecords of adults with mild to moderate hypoxemia due to coronavirus type 2. InterventionsNone. Main variables of interestNeed for intubation or mortality. Results159 patients were included in the study, with a ratio by support of 2:10 (H_CPAP:HFNO). The 46.5% were women, with no significant differences by sex according to support (p = 0.99, Fisher test). The APACHE II score, for HFNO, had a median of 10.5, 3.5 units higher than H_CPAP (p < 0.01, Wilcoxon rank sum). The risk of intubation in HFNO was 42.1% and in H_CPAP 3.8%, with a significant risk reduction of 91% (95% CI: 36.9%–98.7%; p < 0.01). APACHE II does not modify or confound the support and intubation relationship (p > 0.2, binomial regression); however, it does confound the support and mortality relationship (p = 0.82, RR homogeneity test). Despite a 79.1% reduction in mortality risk with H_CPAP, this reduction was not statistically significant (p = 0.11, binomial regression). ConclusionsThe use of Helmet CPAP, when compared to HFNO, was an effective therapeutic ventilatory support strategy to reduce the risk of intubation in patients with mild to moderate hypoxemia caused by coronavirus type 2 in inpatient units other than intensive care. The limitations associated with the difference in size, age and severity between the arms could generate bias.

Comparison of the Efficacies of High-Flow Nasal Cannula Oxygen Therapy and Non-invasive Nasal Cannula Ventilation in Preventing Intubation.

This study aimed to compare high-flow nasal cannula oxygen therapy (nc-HFOT) and non-invasive nasal cannula ventilation (nc-NIV) in terms of intubation requirements. The study was conducted retrospectively on cases followed up in the pediatric intensive care unit (PICU) between October 2019 and December 2021. Of all cases, 43 (55.8%) were male, and the median age was 16 months. The median PRISM-3 score for all cases was 2.5 (range: 0-3). Among the cases 45 cases (58.4%) received nc-HFOT treatment, and 32 cases (41.6%) received nc-NIV treatment. The median duration of respiratory support for all cases was 2 days, and 14 cases (18.2%) needed intubation. The median PICU stay day for all cases was 7 days, and the median hospital stay day was 11 days. The median age, PICU, and hospital stay days of the nc-NIV group were significantly higher (P < .05). In the logistic regression analysis, the probability of requiring intubation in cases initially nc-NIV was performed was found to be 4.95 times higher than those using nc-HFOT (OR: 4.95, 95% CI: 1.3-18.8, P = 0.01). Additionally, cases with underlying chronic diseases were found to have a 5.9 times increased likelihood of requiring intubation compared to those without (OR: 5.9, 95% CI: 1.41-24.5, P = .01). Five cases (6.5%) were lost during intensive care stay. The application of nc-NIV increases intubation by 4.95 times compared to the application of nc-HFOT. The intubation rate in cases with underlying chronic diseases is also 5.9 times higher than those without.

Application of high flow nasal canula in patients with pulmonary edema caused by seawater drowning

To investigate the therapeutic effect of high-flow nasal cannula oxygen therapy (HFNC) and non-invasive positive pressure ventilation (NPPV) on patients with pulmonary edema caused by seawater drowning. A retrospective analysis method was used. Based on the Utstein database of emergency drowning in the First Hospital of Qinhuangdao, the clinical data of patients with seawater drowning pulmonary edema admitted to the emergency medicine department of the First Hospital of Qinhuangdao from January 1, 2019 to December 31, 2022 were collected. The patients were divided into NPPV group and HFNC group according to different ventilation methods. The general data, endotracheal intubation rate in 7 days, arterial blood gas analysis indexes [arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), arterial oxygen saturation (SaO2)] and hemodynamic indexes (systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, blood lactic acid) before and after treatment, length of stay in intensive care unit (ICU), oxygen therapy comfort of the two groups were compared. A total of 54 patients were enrolled, including 21 patients in the NPPV group and 33 patients in the HFNC group. There were no significant differences in gender, age, state of consciousness and other general information between the two groups. Compared with NPPV group, the rate of endotracheal intubation in HFNC group within 7 days was significantly lower [24.2% (8/33) vs. 33.3% (7/21), P < 0.05]. Before treatment, there were no significant differences in arterial blood gas analysis and hemodynamics between the two groups. After treatment, the above indexes in both groups were significantly improved compared with those before treatment, and PaO2, SaO2, systolic blood pressure, diastolic blood pressure and mean arterial pressure in HFNC group were significantly higher than those in NPPV group [PaO2 (mmHg, 1 mmHg≈0.133kPa): 93.56±6.37 vs. 82.14±6.25, SaO2: 1.02±0.09 vs. 0.95±0.11, systolic blood pressure (mmHg): 117.37±8.43 vs. 110.42±8.38, diastolic blood pressure (mmHg): 79.43±7.61 vs. 72.21±4.32, mean arterial pressure (mmHg): 92.34±6.32 vs. 85.12±5.38], PaCO2, heart rate and blood lactic acid were significantly lower than those in NPPV group [PaCO2 (mmHg) : 34.26±5.63 vs. 37.24±6.22, heart rate (times/min): 73.38±7.56 vs. 86.25±5.41, blood lactic acid (mmol/L): 1.38±0.36 vs. 2.25±1.14], and the differences were statistically significant (all P < 0.05). In addition, the length of ICU stay in HFNC group was significantly shorter than that in NPPV group (days: 13.30±2.38 vs. 16.27±4.26), and the comfort rate of oxygen therapy was significantly higher than that in NPPV group [66.7% (22/33) vs. 42.8% (9/21)], with statistical significance (all P < 0.05). HFNC can improve the oxygenation of patients with pulmonary edema caused by seawater drowning, improve hemodynamics, reduce the rate of tracheal intubation, shorten the length of ICU stay, and improve the comfort of oxygen therapy, which has certain clinical application value.

DCROX and ROX Indices Predict Clinical Outcomes in Patients with COVID-19 Pneumonia Treated with High-Flow Nasal Cannula Oxygen Therapy.

High-flow nasal cannula (HFNC) therapy is a common respiratory support in patients with COVID-19 pneumonia. Predictive tools for the evaluation of successful weaning from HFNC therapy for COVID-19 pneumonia have been limited. This study aimed to develop a new predictor for weaning success from HFNC treatment in patients with COVID-19 pneumonia. We conducted a retrospective cohort study at Thammasat University Hospital, Thailand. Patients with COVID-19 pneumonia requiring HFNC therapy from April 2020 to September 2021 were included. The ROX index was defined as the ratio of oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) to respiratory rate. The CROX index was defined as the ratio of C-reactive protein (CRP) to the ROX index. dCROX was defined as the difference in CROX index between 24 hours and 72 hours. Weaning success was defined as the ability to sustain spontaneous breathing after separation from HFNC without any invasive or noninvasive ventilatory support for ≥48 hours or death. A total of 106 patients (49.1% male) were included. The mean age was 62.1 ± 16.2 years. Baseline SpO2/FiO2 was 276.1 ± 124.8. The rate of HFNC weaning success within 14 days was 61.3%. The best cutoff value of the dCROX index to predict HFNC weaning success was 3.15 with 66.2% sensitivity, 70.7% specificity, and an area under the ROC curve (AUC) of 0.71 (95% CI: 0.59-0.81, p < 0.001). The best cutoff value of the ROX index was 9.13, with 75.4% sensitivity, 78.0% specificity, and an AUC of 0.79 (95% CI: 0.69-0.88, p < 0.001). ROX index has the highest accuracy for predicting successful weaning from HFNC in patients with COVID-19 pneumonia. dCROX index is the alternative tool for this setting. However, a larger prospective cohort study is needed to verify these indices for determining separation from HFNC therapy. This trial is registered with TCTR20221107004.

Enhancing exercise tolerance in interstitial lung disease with high-flow nasal cannula oxygen therapy: A randomized crossover trial.

Interstitial lung disease (ILD) is characterized by dyspnoea on exertion and exercise-induced hypoxaemia. High-flow nasal cannula (HFNC) therapy reduces the respiratory workload through higher gas flow and oxygen supplementation, which may affect exercise tolerance. This study aimed to examine the effects of oxygen and gas flow rates through HFNC therapy on exercise tolerance in ILD patients. We conducted three-treatment crossover study. All ILD patients performed the exercises on room air (ROOM AIR setting: flow, 0 L/min; fraction of inspired oxygen [FiO2 ], 0.21), HFNC (FLOW setting: flow 40 L/min, FiO2 0.21), and HFNC with oxygen supplementation (FLOW + OXYGEN setting: flow 40 L/min, FiO2 0.6). The primary endpoint was the endurance time, measured using constant-load cycle ergometry exercise testing at a peak work rate of 80%. Twenty-five participants (10 men, 71.2 ± 6.7 years) were enrolled. The increase in exercise duration between the ROOM AIR and FLOW was 46.3 s (95% CI, -6.1 to 98.7; p = 0.083), and the FLOW and FLOW + OXYGEN was 91.5 s (39.1-143.9; p < 0.001). The percutaneous oxygen saturation (SpO2 ) at rest was significantly higher with the FLOW + OXYGEN setting than with the ROOM AIR and FLOW settings, and the difference persisted during exercise. At equivalent time points during exercise, the SpO2 with the FLOW setting was significantly higher than that with the ROOM AIR setting. Oxygen supplementation in HFNC therapy improved exercise tolerance and SpO2 . We found that gas flow alone did not improve exercise tolerance, but improved SpO2 during exercise.

Comparison of high-flow nasal cannula oxygenation and non-invasive ventilation for postoperative pediatric cardiac surgery: a meta-analysis.

To evaluate the efficacy of high-flow nasal cannula oxygenation (HFNC) versus non-invasive ventilation (NIV) in pediatric patients post-congenital heart surgery (CHS) through a meta-analysis. A comprehensive literature search was conducted across the Chinese biomedical literature database, Vip database, CNKI, Wanfang, PubMed, Embase, Cochrane Library, and Web of Science until December 20, 2022. We selected RCTs or cohort studies that met inclusion criteria for a meta-analysis using RevMan 5.4 software. Our search yielded five publications, comprised of one randomized controlled trial and four cohort studies. Meta-analysis revealed a significant reduction in reintubation rates in children post-CHS treated with HFNC as compared to NIV [RR = 0.36, 95%CI(0.25 ~ 0.53), P < 0.00001]. There was also a notable reduction in the duration of ICU stay [MD = -4.75, 95%CI (-9.38 ~ -0.12), P = 0.04]. No statistically significant differences were observed between HFNC and NIV in terms of duration of mechanical ventilation, 24h PaO2, and PaCO2 post-treatment (P > 0.05). Furthermore, both groups showed no significant difference in the duration of extracorporeal circulation [MD = -8.27, 95%CI(-17.16 ~ 0.62), P = 0.07]. For pediatric patients post-CHS, HFNC appears to be more effective than NIV in reducing reintubation rates and shortening the CICU stay.

High-flow nasal cannula oxygen versus noninvasive ventilation for the management of acute cardiogenic pulmonary edema: a randomized controlled pilot study.

Whether high-flow nasal oxygen can improve clinical signs of acute respiratory failure in acute heart failure (AHF) is uncertain. To compare the effect of high-flow oxygen with noninvasive ventilation (NIV) on respiratory rate in patients admitted to an emergency department (ED) for AHF-related acute respiratory failure. Multicenter, randomized pilot study in three French EDs. Adult patients with acute respiratory failure due to suspected AHF were included. Key exclusion criteria were urgent need for intubation, Glasgow Coma Scale <13 points or hemodynamic instability. Patients were randomly assigned to receive high-flow oxygen (minimum 50 l/min) or noninvasive bilevel positive pressure ventilation. The primary outcome was change in respiratory rate within the first hour of treatment and was analyzed with a linear mixed model. Secondary outcomes included changes in pulse oximetry, heart rate, blood pressure, blood gas samples, comfort, treatment failure and mortality. Among the 145 eligible patients in the three participating centers, 60 patients were included in the analysis [median age 86 (interquartile range (IQR), 90; 92) years]. There was a median respiratory rate of 30.5 (IQR, 28; 33) and 29.5 (IQR, 27; 35) breaths/min in the high-flow oxygen and NIV groups respectively, with a median change of -10 (IQR, -12; -8) with high-flow nasal oxygen and -7 (IQR, -11; -5) breaths/min with NIV [estimated difference -2.6 breaths/min (95% confidence interval (CI), -0.5-5.7), P = 0.052] at 60 min. There was a median SpO2 of 95 (IQR, 92; 97) and 96 (IQR, 93; 97) in the high-flow oxygen and NIV groups respectively, with a median change at 60 min of 2 (IQR, 0; 5) with high-flow nasal oxygen and 2 (IQR, -1; 5) % with NIV [estimated difference 0.8% (95% CI, -1.1-2.8), P = 0.60]. PaO2, PaCO2 and pH did not differ at 1 h between groups, nor did treatment failure, intubation and mortality rates. In this pilot study, we did not observe a statistically significant difference in changes in respiratory rate among patients with acute respiratory failure due to AHF and managed with high-flow oxygen or NIV. However, the point estimate and its large confidence interval may suggest a benefit of high-flow oxygen. NCT04971213 (https://clinicaltrials.gov).

Clinical research progress in non-invasive positive pressure ventilation in 2023

Non-invasive positive pressure ventilation (NPPV) is a widely used method of providing respiratory support in a variety of clinical settings, including emergency departments, general wards, and intensive care units. The relevant research articles on NPPV published between 1st October 2022 and 30th September 2023 were retrieved from Medline and reviewed. In the management of acute respiratory failure (ARF) associated with COVID-19, studies have highlighted the significant influence of regional economic status on the choice of respiratory support strategies. It has been observed that NPPV is more suitable for patients with mild to moderate acute respiratory distress syndrome (ARDS) than for those with severe ARDS, as the latter group has an increased risk of delayed intubation. In addition, patients with severe dyspnea tended to benefit more from NPPV compared with high flow nasal cannula (HFNC) and conventional oxygen therapy, with a reduced risk of self-induced lung injury. For non-COVID-19-related ARF, research shows no significant differences in mortality and intubation rates between HFNC and NPPV in patients with hypercapnic ARF. The updated HACOR score and ROX score have been validated to have a high predictive value for clinical outcomes in patients receiving NPPV for hypoxemic ARF. With regard to weaning from invasive mechanical ventilation, immediate application of NPPV after extubation showed a lower mortality rate compared to continued invasive weaning. Moreover, NPPV with active humidification significantly decreased the reintubation rate within 7 days after extubation compared with HFNC. The choice between using NPPV and HFNC should be based on the specific etiology of the patient's condition. The potential effect of noninvasive high-frequency oscillatory ventilation on CO2 clearance was also investigated.

Ratio of oxygen saturation index for predicting high-flow nasal cannula outcomes in emergency department for COVID-19 patients with severe hypoxemia: A retrospective study.

High-flow nasal cannula (HFNC) oxygen therapy has been used as an initial ventilatory support for coronavirus disease 2019 (COVID-19) patients with mixed levels of acute hypoxemic respiratory failure (AHRF). However, the effectiveness of HFNC when used as initial ventilatory support in COVID-19 patients with severe AHRF exclusively is not well documented. Ratio of oxygen saturation (ROX) index (ROX = [SpO2/fraction of inspired oxygen]/respiratory rate) was shown to predict the outcome of HFNC in intensive care unit patients. Our study aimed to evaluate the utility of the ROX index for predicting HFNC therapy success/failure in COVID-19 patients with severe AHRF when HFNC is used as the first line of ventilatory support. Retrospective study in 67 COVID-19 patients with severe AHRF receiving HFNC in the emergency department at a tertiary care academic medical center. ROX index was determined at 0, 2, 6, 12, and 24 h of HFNC onset. The need to escalate to noninvasive or invasive ventilatory support was documented. The receiver operating characteristic curves were performed and areas under the curves (AUCs) were calculated to evaluate the accuracy of ROX index for differentiating between patients who will succeed or fail HFNC therapy. HFNC therapy was successful in 19 patients (28.1%) and failed in 48 patients (71.6%). ROX index after 6 h of HFNC initiation had the best predictive capacity for the outcome of HFNC therapy (AUC = 0.78). ROX index >4.4 at 6 h of HFNC onset was significantly associated with HFNC success/failure. ROX index at 6 h after initiating HFNC therapy in COVID-19 patients with severe AHRF has a good predictive capacity for HFNC success/failure.

The effects of flow settings during high-flow nasal cannula oxygen therapy for neonates and young children.

During neonatal and paediatric high-flow nasal cannula therapy, optimising the flow setting is crucial for favourable physiological and clinical outcomes. However, considerable variability exists in clinical practice regarding initial flows and subsequent adjustments for these patients. Our review aimed to summarise the impact of various flows during high-flow nasal cannula treatment in neonates and children. Two investigators independently searched PubMed, Embase, Web of Science, Scopus and Cochrane for in vitro and in vivo studies published in English before 30 April 2023. Studies enrolling adults (≥18 years) or those using a single flow setting were excluded. Data extraction and risk of bias assessments were performed independently by two investigators. The study protocol was prospectively registered with PROSPERO (CRD42022345419). 38 406 studies were identified, with 44 included. In vitro studies explored flow settings' effects on airway pressures, humidity and carbon dioxide clearance; all were flow-dependent. Observational clinical studies consistently reported that higher flows led to increased pharyngeal pressure and potentially increased intrathoracic airway pressure (especially among neonates), improved oxygenation, and reduced respiratory rate and work of breathing up to a certain threshold. Three randomised controlled trials found no significant differences in treatment failure among different flow settings. Flow impacts exhibited significant heterogeneity among different patients. Individualising flow settings in neonates and young children requires consideration of the patient's peak inspiratory flow, respiratory rate, heart rate, tolerance, work of breathing and lung aeration for optimal care.

Clinical characteristics and mortality prediction of patients admitted to the Hong Kong East Cluster intensive care units in the COVID‐19 fifth wave

AbstractIntroductionCOVID‐19 has been threatening global public health since 2019. To address the overwhelming caseload, several tools were developed to predict prognosis and aid triage of critically ill patients for intensive care. Currently, there is a lack of local data on the validity of such tools.ObjectiveThe objective of this study is to identify the predictors of intensive care unit (ICU) mortality in COVID‐19 patients in Hong Kong and externally validate the different scoring systems.MethodsA retrospective cohort analysis of patients admitted to the HKEC ICUs from 1 January 2022 to 30 April 2022 was performed. We collected data on patient demographics, vaccination status, laboratory parameters, and clinical outcomes including need for organ support and mortality. Clinical severities were estimated by Sequential Organ Failure Score, 4C Mortality Score, COVID‐Gram score, and Acute Physiology and Chronic Health Evaluation (APACHE) IV score based on the original studies. Comparison between individual scoring systems' performance on hospital mortality was conducted and summarized.ResultsIn these four months, 137 patients with COVID‐19 admitted to ICUs of Ruttonjee Hospital and Pamela Youde Nethersole Eastern Hospital were recruited. 64 patients (46.7%) were admitted for COVID‐19 related respiratory failure, among which mortality was 66.7%. The overall hospital and ICU mortality were 21.9% and 13.1%, respectively. Invasive mechanical ventilation (IMV) (OR 3.221, p 0.034), high flow nasal cannula (HFNC) oxygen therapy (OR 3.107, p 0.039), and higher APACHE IV score (OR 1.043, p &lt; 0.001) were independent predictors of hospital mortality using multivariate analysis. The scoring systems had good performance in mortality prediction in our population. The APACHE IV score (AUROC 0.79, 95% CI 0.698–0.894) and 4C Mortality Score (AUROC 0.751, 95% CI 0.657–0.844) outperformed other scoring systems in predicting hospital mortality.ConclusionIn patients with COVID‐19, the use of IMV or HFNC and APACHE IV score were independent risk factors for hospital mortality. The APACHE IV and the 4C Mortality Score were most useful in our population for predicting ICU and hospital mortality.

Asymmetrical high-flow nasal cannula performs similarly to standard interface in patients with acute hypoxemic post-extubation respiratory failure: a pilot study

BackgroundStandard high-flow nasal cannula (HFNC) is a respiratory support device widely used to manage post-extubation hypoxemic acute respiratory failure (hARF) due to greater comfort, oxygenation, alveolar recruitment, humidification, and reduction of dead space, as compared to conventional oxygen therapy. On the contrary, the effects of the new asymmetrical HFNC interface (Optiflow® Duet system (Fisher & Paykel, Healthcare, Auckland, New Zealand) is still under discussion. Our aim is investigating whether the use of asymmetrical HFNC interface presents any relevant difference, compared with the standard configuration, on lung aeration (as assessed by end-expiratory lung impedance (EELI) measured by electrical impedance tomography (EIT)), diaphragm ultrasound thickening fraction (TFdi) and excursion (DE), ventilatory efficiency (estimated by corrected minute ventilation (MV)), gas exchange, dyspnea, and comfort.MethodsPilot physiological crossover randomized controlled study enrolling 20 adults admitted to the Intensive Care unit, invasively ventilated for at least 24 h, and developing post-extubation hARF, i.e., PaO2/set FiO2 < 300 mmHg during Venturi mask (VM) within 120 min after extubation. Each HFNC configuration was applied in a randomized 60 min sequence at a flow rate of 60 L/min.ResultsGlobal EELI, TFdi, DE, ventilatory efficiency, gas exchange and dyspnea were not significantly different, while comfort was greater during asymmetrical HFNC support, as compared to standard interface (10 [7–10] and 8 [7–9], p-value 0.044).ConclusionsIn post-extubation hARF, the use of the asymmetrical HFNC, as compared to standard HFNC interface, slightly improved patient comfort without affecting lung aeration, diaphragm activity, ventilatory efficiency, dyspnea and gas exchange.Clinical trial numberClinicalTrial.gov. Registration number: NCT05838326 (01/05/2023).New & noteworthyThe asymmetrical high-flow nasal cannula oxygen therapy (Optiflow® Duet system (Fisher & Paykel, Healthcare, Auckland, New Zealand) provides greater comfort as compared to standard interface; while their performance in term of lung aeration, diaphragm activity, ventilatory efficiency, dyspnea, and gas exchange is similar.