Lung ultrasound score to monitor COVID-19 pneumonia progression in patients with ARDS

Abstract

COVID-19 pneumonia typically begins with subpleural ground glass opacities with progressive extension on computerized tomography studies. Lung ultrasound is well suited to this interstitial, subpleural involvement, and it is now broadly used in intensive care units (ICUs). The extension and severity of lung infiltrates can be described numerically with a reproducible and validated lung ultrasound score (LUSS). We hypothesized that LUSS might be useful as a tool to non-invasively monitor the evolution of COVID-19 pneumonia at the bedside. LUSS monitoring was rapidly implemented in the management of our COVID-19 patients with RT-PCR-documented COVID-19. The LUSS was evaluated repeatedly at the bedside. We present a graphic description of the course of LUSS during COVID-19 in 10 consecutive patients admitted in our intensive care unit with moderate to severe ARDS between March 15 and 30th. LUSS appeared to be closely related to the disease progression. In successfully extubated patients, LUSS decreased and was lower than at the time of intubation. LUSS increased inexorably in a patient who died from refractory hypoxemia. LUSS helped with the diagnosis of ventilator-associated pneumonia (VAP), showing an increased score and the presence of new lung consolidations in all 5 patients with VAPs. There was also a good agreement between CT-scans and LUSS as for the presence of lung consolidations. In conclusion, our early experience suggests that LUSS monitoring accurately reflect disease progression and indicates potential usefulness for the management of COVID-19 patients with ARDS. It might help with early VAP diagnosis, mechanical ventilation weaning management, and potentially reduce the need for X-ray and CT exams. LUSS evaluation is easy to use and readily available in ICUs throughout the world, and might be a safe, cheap and simple tool to optimize critically ill COVID-19 patients care during the pandemic.

Fig 1. Clinical course and lung ultrasound score (LUSS) evolution in 10 COVID-19 patients.

For each timepoint the numerical LUSS is indicated above the corresponding symbol (blue diamond if ultrasound showed only interstitial infiltrates and red if it also showed at least one lung consolidation). Arrows indicate occurrence of a clinically-diagnosed ventilator-associated pneumonia. Mechanical ventilation-free periods are highlighted in green. Patient #5 died of refractory hypoxemia. Patient #6 was extubated on April 7^th but was placed under non-invasive ventilation due to post-extubation acute respiratory failure. Patients #4 and #9 were discharged alive from intensive care during the study period. NIV: non-invasive ventilation; yo: years-old.