Lung Ultrasound Severity Index: Development and Usefulness in Patients with Suspected SARS-Cov-2 Pneumonia-A Prospective Study

Ultrasound Med Biol. 2021 Dec;47(12):3333-3342. doi: 10.1016/j.ultrasmedbio.2021.08.018. Epub 2021 Aug 31.

Abstract

Coronavirus disease 2019 (COVID-19) has spread across the world with a strong impact on populations and health systems. Lung ultrasound is increasingly employed in clinical practice but a standard approach and data on the accuracy of lung ultrasound are still needed. Our study's objective was to evaluate lung ultrasound diagnostic and prognostic characteristics in patients with suspected COVID-19. We conducted a monocentric, prospective, observational study. Patients with respiratory distress and suspected COVID-19 consecutively admitted to the Emergency Medicine Unit were enrolled. Lung ultrasound examinations were performed blindly to clinical data. Outcomes were diagnosis of COVID-19 pneumonia and in-hospital mortality. One hundred fifty-nine patients were included in our study; 66% were males and 63.5% had a final diagnosis of COVID-19. COVID-19 patients had a higher mortality rate (18.8% vs. 6.9%, p = 0.04) and Lung Ultrasound Severity Index (16.14 [8.71] vs. 10.08 [8.92], p < 0.001) compared with non-COVID-19 patients. This model proved able to distinguish between positive and negative cases with an area under the receiver operating characteristic (AUROC) equal to 0.72 (95% confidence interval [CI]: 0.64-0.78) and to predict in-hospital mortality with an AUROC equal to 0.81 (95% CI: 0.74-0.86) in the whole population and an AUROC equal to 0.76 (95% CI: 0.66-0.84) in COVID-19 patients. The Lung Ultrasound Severity Index can be a useful tool in diagnosing COVID-19 in patients with a high pretest probability of having the disease and to identify, among them, those with a worse prognosis.

Keywords: Emergency department; Lung ultrasound; Point-of-care-ultrasound; Prognostication; SARS-COV-2 pneumonia.

Publication types

  • Observational Study

MeSH terms

  • COVID-19 / diagnostic imaging*
  • COVID-19 / mortality
  • Emergency Service, Hospital
  • Female
  • Hospital Mortality
  • Humans
  • Italy
  • Lung / diagnostic imaging*
  • Male
  • Middle Aged
  • Point-of-Care Systems
  • Prognosis
  • Prospective Studies
  • SARS-CoV-2
  • Severity of Illness Index*
  • Ultrasonography