Point-of-care lung ultrasound predicts severe disease and death due to COVID-19: a prospective cohort study. (preprint)

Objective: The clinical utility of point-of-care lung ultrasound (LUS) for disease severity triage of hospitalized patients with COVID-19 is unclear. Design: Prospective cohort study Setting: A large tertiary care center in Maryland, USA between April 2020 to September 2021. Patients: Hospitalized adults (18 years of age or greater) with positive SARS-CoV-2 RT-PCR results. Interventions: None. Measurements and Main Results: All patients were scanned using a standardized protocol including 12 lung zones and followed to determine clinical outcomes until hospital discharge and vital status at 28-days. Ultrasounds were independently reviewed for lung and pleural line artifacts and abnormalities, and the mean Lung Ultrasound Score (ranging from 0 to 3) across lung zones (mLUSS) was determined. The primary outcome was time to ICU-level care, defined as high flow oxygen, noninvasive, or mechanical ventilation, within 28-days of the initial ultrasound. Cox proportional hazards regression models adjusted for age and sex were fit for mLUSS and each ultrasound covariate. A total of 264 participants were enrolled in the study; the median age was 59 years and 114 (43.2) % of participants were female. The median mLUSS was 1 (interquartile range: 0.5 to 1.3). Following enrollment, 29 (11.0%) participants went on to require ICU-level care and 14 (5.3%) subsequently died by 28 days. Each increase in mLUSS at enrollment was associated with disease progression to ICU-level care (aHR = 3.63; 95% CI: 1.23 to 10.65) and 28-day mortality (aHR = 4.50; 95% CI: 1.52 to 13.31). Pleural line abnormalities were independently associated with disease progression to ICU-level care (aHR = 18.86; CI: 1.57 to 226.09). Conclusions: Participants with a mLUSS of 1 or more or pleural line changes on LUS had an increased likelihood of subsequent requirement of high flow oxygen or greater. LUS is a promising tool for assessing risk of COVID-19 progression at the bedside.

COVID-19 Advanced Respiratory Care Educational Training Program for Healthcare Workers in Lesotho: An Observational Study (preprint)

Objectives: To develop and implement a Low Dose, High Frequency (LDHF) advanced respiratory care training program for COVID-19 care in Lesotho. Design: Prospective pre-post training evaluation. Setting: Lesotho has limited capacity in advanced respiratory care. Participants: Physicians and nurses. Interventions: Due to limited participation May-September 2020 the LDHF approach was modified into a traditional one-day offsite training November 2020 that reviewed respiratory anatomy and physiology, clinical principles for conventional oxygen, heated high flow nasal cannula, and non-invasive ventilation management. Basic mechanical ventilation principles were introduced. Outcome measures: Participants completed a twenty-question multiple choice examination immediately before and after the one-day training. Paired t-tests were used to evaluate the difference in average participant pre- and post-training examination scores. Results: Pre- and post-training examinations were completed by 46/53 (86.7%) participants, of whom 93.4% (n=43) were nurses. The overall mean pre-training score was 44.8% (standard deviation [SD], 12.4.%). Mean scores improved by an average of 23.7 percentage points (95% confidence interval [CI] 19.7, 27.6 percentage points, p<0.001) on the post-training examination to a mean score of 68.5% (SD, 13.6%). Performance on basic and advanced respiratory categories also improved by 17.7 (95% CI: 11.6, 23.8) and 25.6 percentage points (95% CI: 20.4, 30.8) (p<0.001). Likewise, mean examination scores increased on the post-training test, compared to pre-training, for questions related to respiratory management (29.6 percentage points (95% CI: 24.1, 35.0) and physiology (17.4 percentage points (95% CI: 12.0, 22.8). Conclusions: A LDHF training approach was not feasible during this relatively early period of the COVID-19 pandemic in Lesotho. Despite clear knowledge gains the modest post-training examination scores coupled with limited physician engagement suggest healthcare workers require alternative educational strategies before higher advanced care like mechanical ventilation is implementable. Conventional and high flow oxygen are better aligned with post-training healthcare worker knowledge levels and rapid implementation.