The lung ultrasound "Rule of 7" in the prognosis of COVID-19 patients: Results from a prospective multicentric study

Comparison of lung ultrasound scoring systems for the prognosis of COVID-19 in the emergency department: An international prospective cohort study

Purpose

The purpose of this study was to evaluate whether the lung ultrasound (LUS) scores applied to an international cohort of patients presenting to the emergency department (ED) with suspected COVID-19, and subsequently admitted with proven disease, could prognosticate clinical outcomes.

Methods

This was an international, multicentre, prospective, observational cohort study of patients who received LUS and were followed for the composite primary outcome of intubation, intensive care unit (ICU) admission or death. LUS scores were later applied including two 12-zone protocols ('de Alencar score' and 'CLUE score'), a 12-zone protocol with lung and pleural findings ('Ji score') and an 11-zone protocol ('Tung-Chen score'). The primary analysis comprised logistic regression modelling of the composite primary outcome, with the LUS scores analysed individually as predictor variables.

Results

Between April 2020 to April 2022, 129 patients with COVID-19 had LUS performed according to the protocol and 24 (18.6%) met the composite primary endpoint. No association was seen between the LUS score and the composite primary end point for the de Alencar score [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97-1.11; P = 0.29], the CLUE score (OR = 1.03; 95% CI: 0.96-1.10; P = 0.40), the Ji score (OR = 1.02; 95% CI: 0.97-1.07; P = 0.40) or the Tung-Chen score (OR = 1.02; 95% CI: 0.97-1.08).

Discussion

Compared to these earlier studies performed at the start of the pandemic, the negative outcome of our study could reflect the changing scenario of the COVID-19 pandemic, including patient, disease, and system factors. The analysis suggests that the study may have been underpowered to detect a weaker association between a LUS score and the primary outcome.

Conclusion

In an international cohort of adult patients presenting to the ED with suspected COVID-19 disease who had LUS performed and were subsequently admitted to hospital, LUS severity scores did not prognosticate the need for invasive ventilation, ICU admission or death.

Simplified Lung Ultrasound Examination and Telehealth Feasibility in Early COVID-19 Infection

BACKGROUND

In COVID-19, inpatient studies have demonstrated that lung ultrasound B-lines relate to disease severity and mortality and can occur in apical regions that can be imaged by the patients themselves. However, as illness begins in an ambulatory setting, we sought to determine the prevalence of B-lines in early outpatient infection and then test the accuracy of their detection using telehealth and automated methods.

METHODS

Consecutive adult patients (N=201) with positive testing for SARS-CoV-2, at least one clinical risk factor, and mild-moderate disease were prospectively enrolled at a monoclonal antibody infusion clinic. Physician imaging of the lung apices for 3 B-lines (ULC+) using 3MHz ultrasound was performed on all patients for prevalence data and served as the standard for a nested subset (n=50) to test the accuracy of telehealth methods, including patient self-imaging and automated B-line detection. Patient characteristics, vaccination data and hospitalizations were analyzed for associations with ULC+.

RESULTS

Mean patient age of 54 ±15 years, all lacking hypoxemia or fever, ULC+ was present in 55/201(27%) at a median of 7 symptomatic days (IQR:5-8) and in 4/5 patients who were later hospitalized (p=0.03). ULC+ was associated with unvaccinated status (OR=4.11[95% CI:1.85-9.33], p=0.001), diabetes (OR=2.56[95% CI:1.08-6.05], p=0.03), male sex (OR=2.14[95% CI:1.07-4.37], p=0.03), and hypertension/cardiovascular disease (OR=2.06[95% CI:1.02-4.23], p=0.04), while adjusting for BMI >25kg/m². Telehealth and automated B-line detection had 84% and 82% accuracy, respectively.

CONCLUSIONS

In high-risk outpatients, B-lines in the upper lungs were common in early COVID-19 infection, related to subsequent hospitalization, and could be detected by telehealth and automated methods.