POCUS in COVID-19
》Make sure you check out the Ultrasound Podcast COVID-19 episode for more discussion of how to use POCUS in this disease!《
Background
COVID-19 is the worst pandemic we have seen for a long time. People are using ultrasound at the point-of-care to detect lung findings on these patients. Here are some of the proposed benefits of POCUS:
Fast, bedside, no radiation
Likely more sensitive than chest xray
Easier to disinfect equipment compared to CT scan
Lends itself to repeat examinations for monitoring disease course
The Studies
There are two main articles published thus far:
A preliminary study on the ultrasonic manifestations of peripulmonary lesions of non-critical novel coronavirus pneumonia (COVID-19) February 26, 2020
Findings of lung ultrasonography of novel corona virus pneumonia during the 2019–2020 epidemic Intensive Care Medicine March 12, 2020
Summary of Article 1
Retrospectively looked at the lung ultrasounds done on 20 COVID19 patients in Xi’an Chest hospital
All patients had an epidemiologic history, infectious symptoms, and positive blood or respiratory testing. Unclear what made these “non-critical” patients. No exclusion criteria noted
Used a convex array and linear. A protective barrier and 75% alcohol solution were used to protect and disinfect.
Protocol: 12 area examination - Anterior and posterior axillary lines used to make an anterior, lateral, and posterior area, these were further divided into upper and lower zones. Therefore there were 6 zones per lung, total of 12 for the whole exam.
Two physicians with more than 5 years of experience in ultrasound reviewed all of these scans to draw conclusions about the findings.
Findings
Right and left posterior inferior lungs involved in 75% of cases each, Posterior superior was 50%.
Discontinuous or continuous/fused B -lines were common → 37.9%
Pleural line is unsmooth and rough → 15%
Multiple small patchy subpleural consolidations → 22.1%
Air bronchograms → 15.4%
Local pleural effusions around the lung lesions (10%? Or 18.8%)
Pleural thickening 1-2mm (7.9%? Or 14.6%)
Poor blood flow in lesions (unlike other findings, not everyone had this assessed, 50/54 → 94.3%)
✳Some numbers were only in abstract
Ultrasound missed lesions that were completely intrapulmonary and apical lesions
Summary of Article 2
Also used 12 zone method
Not nearly as much detail - unclear what hospitals involved but authors were from Changsha and Beijing, China.
Findings
Thickening pleural line, irregular pleural line
B-lines - focal and confluent
Consolidations - including air bronchograms
Not that many pleural effusions
A-lines when in recovery
Changes Over Time
Focal B-lines early and in mild infection
Alveolar interstitial syndrome (more consolidation) is in progressive and critically ill patients
Take Home Points
1. POCUS is feasible in COVID-19 and likely can be used to follow disease progression.
2. Findings are commonly bilateral, lower/posterior lung fields, and are similar to other viral pneumonias (B-lines, consolidations, pleural line abnormalities).
3. Research needed to determine how to incorporate POCUS into screening, diagnosis, or management
More Great FOAMed on this Topic
Internet Book of Critical Care - COVID-19
St. Emlyn's COVID-19 Podcast from Italy with Roberto Cosentini
EPICA Podcast - COVID-19 US on My Own Lungs
Butterfly Network - Lung Ultrasound Findings in COVID-19 patients