Association between increased nonaerated lung weight and treatment failure in patients with de novo acute respiratory failure: Difference between high-flow nasal oxygen therapy and noninvasive ventilation in a multicentre retrospective study.

PURPOSE: To determine the association between lung collapse and treatment failure in high-flow nasal cannula oxygen therapy (HFNC) or noninvasive ventilation (NIV). METHODS: We performed a quantitative analysis of chest computed tomography in patients with de novo acute respiratory failure who received HFNC (HFNC group) or NIV (NIV group) between January 2012 and December 2017. In the HFNC and NIV group, the nonaerated lung weight were compared between patients in whom respiratory treatment succeeded or failed, respectively. We used logistic regression to examine the association between the nonaerated lung weight and treatment failure. RESULTS: Treatment failed in 70/118 (59%) patients in the HFNC group and 66/101 (65%) patients in the NIV group. The nonaerated lung weight was significantly greater in unsuccessfully treated patients than in successfully treated patients in the HFNC group (p = 0.005), but not in the NIV group (p = 0.535). Logistic regression revealed that greater nonaerated lung weight was associated with increased risk of HFNC failure (adjusted odds ratio 1.30 per 5% increase, 95% confidence interval 1.09-1.55, p = 0.003) but not of NIV failure. CONCLUSIONS: Patients with a greater nonaerated lung weight had a higher risk of HFNC failure, but not of NIV failure.

Comparison of high-flow nasal cannula oxygen therapy and non-invasive ventilation as first-line therapy in respiratory failure: a multicenter retrospective study.

AIM: To identify which subgroups of respiratory failure could benefit more from high-flow nasal cannula oxygen therapy (HFNC) or non-invasive ventilation (NIV). METHODS: We undertook a multicenter retrospective study of patients with acute respiratory failure (ARF) who received HFNC or NIV as first-line respiratory support between January 2012 and December 2017. The adjusted odds ratios (OR) with 95% confidence intervals (CI) for HFNC versus NIV were calculated for treatment failure and 30-day mortality in the overall cohort and in patient subgroups. RESULTS: High-flow nasal cannula oxygen therapy and NIV were used in 200 and 378 patients, and the treatment failure and 30-day mortality rates were 56% and 34% in the HFNC group and 41% and 39% in the NIV group, respectively. The risks of treatment failure and 30-day mortality were not significantly different between the two groups. In subgroup analyses, HFNC was associated with increased risk of treatment failure in patients with cardiogenic pulmonary edema (adjusted OR 6.26; 95% CI, 2.19-17.87; P < 0.01) and hypercapnia (adjusted OR 3.70; 95% CI, 1.34-10.25; P = 0.01), but the 30-day mortality was not significantly different in these subgroups. High-flow nasal cannula oxygen therapy was associated with lower risk of 30-day mortality in patients with pneumonia (adjusted OR 0.43; 95% CI, 0.19-0.94; P = 0.03) and in patients without hypercapnia (adjusted OR 0.51; 95% CI, 0.30-0.88; P = 0.02). CONCLUSION: High-flow nasal cannula oxygen therapy could be more beneficial than NIV in patients with pneumonia or non-hypercapnia, but not in patients with cardiogenic pulmonary edema or hypercapnia.

Cytokine profile of bronchoalveolar lavage fluid from a mouse model of bronchial asthma during seasonal H1N1 infection.

BACKGROUND: Several studies support the role of viral infections in the pathogenesis of asthma exacerbation. However, several pediatricians believe that influenza virus infection does not exacerbate bronchial asthma, except for influenza A H1N1 2009 pandemic [A(H1N1)pdm09] virus infection. We previously reported that A(H1N1)pdm09 infection possibly induces severe pulmonary inflammation or severe asthmatic attack in a mouse model of bronchial asthma and in asthmatic children. However, the ability of seasonal H1N1 influenza (H1N1) infection to exacerbate asthmatic attacks in bronchial asthma patients has not been previously reported, and the differences in the pathogenicity profiles, such as cytokine profiles, remains unclear in bronchial asthma patients after A(H1N1)pdm09 and H1N1 infections. METHODS: The cytokine levels and viral titers in the bronchoalveolar lavage (BAL) fluid from mice with and without asthma after H1N1 infection (A/Yamagata and A/Puerto Rico strains) were compared. RESULTS: The interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, IL-5, interferon (IFN)-α, IFN-ß, and IFN-γ levels were significantly higher in the BAL fluids from the control/H1N1 mice than from the asthmatic/H1N1 mice. The viral titers in the BAL fluid were also significantly higher in the control/H1N1mice than in the asthmatic/H1N1 mice infected with either A/Yamagata or A/Puerto Rico. CONCLUSIONS: A(H1N1)pdm09 infection, but not H1N1 infection, can induce severe pulmonary inflammation through elevated cytokine levels in a mouse model of asthma.