American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Feb 2022
Long-term Ozone Exposure and Small Airways Dysfunction: The China Pulmonary Health (CPH) Study.
Rationale: It remains unknown whether long-term ozone exposure can impair lung function. Objectives: To investigate the associations between long-term ozone exposure and adult lung function in China. Methods: Lung function results and diagnosis of small airway dysfunction (SAD) were collected from a cross-sectional study, the China Pulmonary Health Study (N = 50,991). ⋯ The association estimates were greater in the COPD group than in the non-COPD group. Conclusions: We found independent associations of long-term ozone exposure with impaired small airway function and higher SAD risks, while the associations with airflow obstruction were weak. Patients with COPD appear to be more vulnerable.
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Am. J. Respir. Crit. Care Med. · Feb 2022
Multicenter Study Meta Analysis Comparative StudyHigh Flow Nasal Oxygen for Severe Hypoxemia: Oxygenation Response and Outcome in COVID-19 Patients.
Rationale: The "Berlin definition" of acute respiratory distress syndrome (ARDS) does not allow inclusion of patients receiving high-flow nasal oxygen (HFNO). However, several articles have proposed that criteria for defining ARDS should be broadened to allow inclusion of patients receiving HFNO. Objectives: To compare the proportion of patients fulfilling ARDS criteria during HFNO and soon after intubation, and 28-day mortality between patients treated exclusively with HFNO and patients transitioned from HFNO to invasive mechanical ventilation (IMV). ⋯ Twenty-eight-day mortality in patients who remained on NIV was 1.6% (1/62), whereas in patients who transitioned from NIV to IMV, it was 44.9% (31/69) (P < 0.001). Overall mortality was 19.0% (35/184) and 24.4% (32/131) for HFNO and NIV, respectively (P = 0.2479). Conclusions: Broadening the ARDS definition to include patients on HFNO with PaO2/FiO2 ⩽300 may identify patients at earlier stages of disease but with lower mortality.
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Am. J. Respir. Crit. Care Med. · Feb 2022
Randomized Controlled TrialRandomized Clinical Trial of Air Cleaners to Improve Indoor Air Quality and COPD Health: Results of the CLEAN AIR STUDY.
Rationale: Indoor particulate matter is associated with worse chronic obstructive pulmonary disease (COPD) outcomes. It remains unknown whether reductions of indoor pollutants improve respiratory morbidity. Objectives: To determine whether placement of active portable high-efficiency particulate air cleaners can improve respiratory morbidity in former smokers. ⋯ In per-protocol analysis, there was a statistically significant difference in primary outcome between the active filter versus sham group (SGRQ, β -4.76 [95% CI, -9.2 to -0.34]) and in moderate exacerbation risk, Breathlessness, Cough, and Sputum Scale, and 6MWD. Participants spending more time indoors were more likely to have treatment benefit. Conclusions: This is the first environmental intervention study conducted among former smokers with COPD showing potential health benefits of portable high-efficiency particulate absolute air cleaners, particularly among those with greater adherence and spending a greater time indoors.
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Am. J. Respir. Crit. Care Med. · Feb 2022
Randomized Controlled Trial Multicenter Study Comparative StudyBeneficial Effects of Non-Invasive Ventilation After Extubation in Obese or Overweight Patients: A Post-Hoc Analysis of a Randomized Clinical Trial.
Rationale: Although noninvasive ventilation (NIV) may prevent reintubation in patients at high risk of extubation failure in ICUs, this oxygenation strategy has not been specifically assessed in obese patients. Objectives: We hypothesized that NIV may decrease the risk of reintubation in obese patients compared with high-flow nasal oxygen. Methods: Post hoc analysis of a multicenter randomized controlled trial (not prespecified) comparing NIV alternating with high-flow nasal oxygen versus high-flow nasal oxygen alone after extubation, with the aim of assessing NIV effects according to patient body mass index (BMI). ⋯ Conclusions: Prophylactic NIV alternating with high-flow nasal oxygen immediately after extubation significantly decreased the risk of reintubation and death compared with high-flow nasal oxygen alone in obese or overweight patients at high risk of extubation failure. By contrast, NIV was not effective in normal or underweight patients. Clinical trial registered with www.clinicaltrials.gov (NCT03121482).