Adjusting diffusing capacity for anemia in patients undergoing allogeneic HCT: a comparison of two methodologies.

Background: Diffusing capacity (DLCO) measurements are affected by hemoglobin. Two adjustment equations are used: Cotes (recommended by ATS/ERS) and Dinakara (used in the hematopoietic stem cell transplantation comorbidity index [HCT-CI]). It is unknown how these methods compare, and which is better from a prognostication standpoint.

Diagnostic Yield of 16S Ribosomal Ribonucleic Acid Gene-Based Targeted Metagenomic Sequencing for Evaluation of Pleural Space Infection: A Prospective Study.

Objective: To better understand the microbial profile of complicated parapneumonic effusions and empyema, and to evaluate whether antimicrobial selection would differ if guided by targeted metagenomic sequencing (tMGS) conventional cultures (CCs) alone.

Patients And Methods: We analyzed the pleural fluid of a cohort of 47 patients undergoing thoracentesis from January 1, 2017 to August 31, 2019, to characterize their microbial profile. All samples underwent 16S ribosomal ribonucleic acid gene polymerase chain reaction, followed by tMGS.

Hypoxaemia in patients with heart failure and preserved ejection fraction.

Aims: It is widely held that heart failure (HF) does not cause exertional hypoxaemia, based upon studies in HF with reduced ejection fraction, but this may not apply to patients with HF and preserved ejection fraction (HFpEF). Here, we characterize the prevalence, pathophysiology, and clinical implications of exertional arterial hypoxaemia in HFpEF.

Methods And Results: Patients with HFpEF (n = 539) and no coexisting lung disease underwent invasive cardiopulmonary exercise testing with simultaneous blood and expired gas analysis.

Use of a Viral Filter to Reduce Exposure to Exhaled Aerosol Does Not Affect Methacholine Dose Delivery During Bronchoprovocation Testing.

Background: Methacholine challenge testing (MCT) is a common bronchoprovocation technique used to assess airway hyper-responsiveness. We previously demonstrated that the addition of a viral filter to the nebulizer exhalation limb substantially reduced expelled particles during MCT. Our aim was to evaluate whether this modification affects the delivered dose of methacholine.

Isolated Elevation in Lung Residual Volume Is Associated With Airway Diseases.

Background: Residual volume (RV) is a derived lung compartment that correlates with air trapping in the context of air flow obstruction on spirometry. The significance of an isolated elevation in RV in the absence of other pulmonary function test (PFT) abnormalities is not well defined. We sought to assess the clinical and radiologic findings associated with isolated elevation in RV.

Aerosol Generation and Mitigation During Methacholine Bronchoprovocation Testing: Infection Control Implications in the Era of COVID-19.

Background: Methacholine bronchoprovocation or challenge testing (MCT) is commonly performed to assess airway hyper-responsiveness in the setting of suspected asthma. Nebulization is an aerosol-generating procedure, but little is known about the risks of MCT in the context of the ongoing coronavirus disease 2019 (COVID-19) pandemic. We aimed to quantify and characterize aerosol generation during MCT by using different delivery methods and to assess the impact of adding a viral filter.

Aerosol Generation During Peak Flow Testing: Clinical Implications for COVID-19.

Background: Peak flow testing is a common procedure performed in ambulatory care. There are currently no data regarding aerosol generation during this procedure. Given the ongoing debate regarding the potential for aerosol transmission of SARS-CoV-2, we aimed to quantify and characterize aerosol generation during peak flow testing.

A Practice Redesign Collaborative for Reducing Hospital Readmission for Chronic Obstructive Pulmonary Disease in an Affiliated Network of Health Care Organizations.

Background: Patients discharged following admissions for acute exacerbations of chronic obstructive pulmonary disease (AE-COPD) frequently require unplanned readmissions, increasing costs and morbidity for thousands of patients suffering from COPD. The Hospital Readmissions Reduction Program provided financial incentives to reduce 30-day readmissions for AE-COPD, but although risk factors for readmission are known, few evidence-based interventions achieve this goal. Members of the Mayo Clinic Care Network (MCCN) formed a collaborative to seek ways to reduce 30-day readmission for patients admitted with AE-COPD.

Particulate generation with different oxygen delivery devices.

Background: The Coronavirus pandemic has a high mortality rate in patients that are mechanically ventilated, which has led to an ever increasing interest in noninvasive forms of oxygenation. The use of these devices has the theoretical risk of increased exposure risk because of possible particulate generation. This study aimed to quantify the particulate generation associated with different oxygen devices.

Characterizing Particulate Generation During Cardiopulmonary Rehabilitation Classes With Patients Wearing Procedural Masks.

Background: The clinical benefits of cardiopulmonary rehabilitation are extensive, including improvements in health-related quality of life, emotional condition, physical function, and overall mortality. The COVID-19 pandemic continues to have a negative impact on center-based cardiopulmonary rehabilitation. Justifiable concern exists that the exercise-related increase in pulmonary ventilation within the rehabilitation classes may lead to the generation of infectious respiratory particles.

Newer Biological Agents in the Treatment of Severe Asthma: Real-World Results from a Tertiary Referral Center.

Purpose: To determine the efficacy of IL-5 inhibitory therapy in severe, refractory asthma in a real-world clinical setting from a tertiary referral center.

Methods: A retrospective chart review of patients with severe asthma treated with IL-5 biologic therapy for ≥ 6 months at Mayo Clinic in Rochester, Minnesota between January 1, 2013 and August 31, 2019.

Results: Over the study period, we identified 63 patients with a mean age of 54 who received an IL-5 inhibitor for ≥ 6 months.

Correlation of Exhaled Nasal Nitric Oxide With Sinus Computed Tomography and Sinonasal Outcome Test Scores: A Cross-sectional Pilot Study.

Background: Computed tomography (CT) of the paranasal sinuses is the diagnostic reference standard for chronic rhinosinusitis and related inflammatory sinus pathology. Nasal nitric oxide (nNO) levels have been investigated as a diagnostic tool in sinus disease because it decreases with sinus obstruction.

Objective: The primary aim of the study was to determine the correlation of passive (baseline) and dynamic (humming) nNO to CT findings of sinus inflammation and to sinonasal symptoms measured by the modified Sinonasal Outcome Test (26 items) (SNOT-26).

Treatment of Interstitial Lung Disease Associated Cough: CHEST Guideline and Expert Panel Report.

Background: Chronic cough in interstitial lung disease (ILD) causes significant impairment in quality of life. Effective treatment approaches are needed for cough associated with ILD.

Methods: This systematic review asked: Is there evidence of clinically relevant treatment effects for therapies for cough in ILD? Studies of adults aged > 18 years with a chronic cough ≥ 8 weeks' duration were included and assessed for relevance and quality.

Sleep and Nocturnal Gastroesophageal Reflux: An Update.

Nocturnal gastroesophageal reflux has been associated with poor sleep quality. Normal physiological adaptations of the aerodigestive system to sleep prolong and intensify nocturnal reflux events. This occurrence leads to sleep disruption, as well as to esophageal, laryngeal, and laryngopharyngeal reflux.

Surgical Management of Chyloptysis.

Chyloptysis is a rare clinical presentation. Diagnosis is challenging and requires recognition of milky-sputum or bronchial casts. We describe a case of chyloptysis secondary to thoracic lymphangiectasia that necessitated surgical ligation of the main thoracic duct and accessory branches.

Rare presentation of an old bug.

We highlight a rare presentation of infection in a 77-year-old woman with a clinical diagnosis of giant cell arteritis 2 months prior to presentation. She was started on 60 mg prednisone that was tapered to 10 mg after 4 weeks following her diagnosis. She presented with a 1-month progressive dyspnoea in the absence of any other symptoms.

Chronic Cough Due to Gastroesophageal Reflux in Adults: CHEST Guideline and Expert Panel Report.

Background: We updated the 2006 ACCP clinical practice guidelines for management of reflux-cough syndrome.

Methods: Two population, intervention, comparison, outcome (PICO) questions were addressed by systematic review: (1) Can therapy for gastroesophageal reflux improve or eliminate cough in adults with chronic and persistently troublesome cough? and (2) Are there minimal clinical criteria to guide practice in determining that chronic cough is likely to respond to therapy for gastroesophageal reflux?

Results: We found no high-quality studies pertinent to either question. From available randomized controlled trials (RCTs) addressing question #1, we concluded that (1) there was a strong placebo effect for cough improvement; (2) studies including diet modification and weight loss had better cough outcomes; (3) although lifestyle modifications and weight reduction may be beneficial in suspected reflux-cough syndrome, proton pump inhibitors (PPIs) demonstrated no benefit when used in isolation; and (4) because of potential carryover effect, crossover studies using PPIs should be avoided.

Evaluation of exhaled nitric oxide's ability to predict methacholine challenge in adults with nonobstructive spirometry.

Background: Compared with methacholine challenge, exhaled nitric oxide is less expensive, is performed as a simpler point-of-care maneuver, and may provide treatment guiding information.

Objective: To determine whether exhaled nitric oxide levels can predict the outcome of methacholine challenge in patients without obvious baseline obstruction.

Methods: This retrospective database and medical record review included adults presenting to a tertiary care center from November 1, 2009, through August 31, 2013, who underwent methacholine challenge and exhaled nitric oxide measurement within 2 weeks of each other.