Ultrasound of Lung for COVID-19 Patients

1. Doctor in Italy, Spain using ultrasound for COVID-19
By Theresa Pablos, AuntMinnie staff writer
March 23, 2020 -- As Europe struggles to cope with the novel coronavirus outbreak,
one doctor in Spain is using point-of-care ultrasound (POCUS) to track his own
COVID-19 disease. His findings echo those of other doctors on the front lines in
showing that ultrasound can help with diagnosis, treatment, and admission
decisions.
Dr. Yale Tung Chen, an emergency medicine physician at an academic hospital in
Madrid, was diagnosed with COVID-19 following a rapid polymerase chain reaction
(PCR) test on March 8. Like his patients, many of his first symptoms were mild -- a
little worse than a common cold, he said during a March 19 webinar on POCUS for
COVID-19.
The first day after Chen's diagnosis he experienced a sore throat, dry cough, and
headache but no lung ultrasound abnormalities. All videos courtesy of Dr. Yale Tung
Chen.
Chen's initial lung ultrasound scans appeared normal, too. However, in the days
following his positive test result, lung sliding started to appear laterally on the
ultrasound scan. He also saw some B-lines and thickening of the pleura. On day
four, he noticed subpleural consolidations for the first time.
By the fourth day following his diagnosis, Chen's ultrasound scan on his left side
showed an increasingly thickened pleural line and two subpleural consolidations.
"As my disease progressed, the lower back started to clear, but then other spots
were affected -- especially on the lateral sides, my axillary fossa, the scapular
fossa," he said.
During this time, Chen's clinical symptoms, including fatigue and cough, would
improve and then worsen again. The cyclical nature of his clinical symptoms
matched what he saw on the ultrasound scans.
"[Lesions] on my back started to clear up, then reappeared a couple of days later,"
he said. "It's something that is quite different from any other viral pneumonia that we
have faced in the past."
Now that he's more than a week out from his positive test result, Chen is doing well.
His oxygen saturation never dropped below 95%, and he hasn't experienced
dysthymia, shortness of breath, or chest pain.

2. On the 12th day after his diagnosis, Chen was feeling better, primarily experiencing
a cough, nausea, and diarrhea. His ultrasound scans showed his subpleural
consolidations were resolving, but he still had thickened pleura and B-lines, as well
as a small effusion.
He also performed cardiac imaging every two days but didn't find anything
remarkable.
Ultrasound warning signs
Chen's findings on his own lung ultrasound scans mirror the findings of doctors in
other European countries. Dr. Mike Stone, former division chief of emergency
ultrasound at Brigham and Women's Hospital in Boston and head of education at
POCUS developer Butterfly, noticed many hospitals in Italy are using lung
ultrasound as a primary or secondary modality for patients with COVID-19.
The turn to ultrasound comes from a lack of resources for other types of chest
imaging, such as CT, which from the start of the outbreak has demonstrated its
utility in detecting COVID-19. And because POCUS can be used bedside, it avoids
concerns about spreading the virus when patients are moved to different locations.
"There are many places currently using lung ultrasound as a primary imaging
modality to try and address some of these concerns," Stone said during a March 19
webinar on POCUS for COVID-19.
In a normal lung ultrasound scan, ribs and shadows are evident with a pleural line
that's bright and smooth, Stone noted. There are also A-lines, which are horizontal
reverberation tracks from an air-filled lung.
But patients with COVID-19 tend to also exhibit focal B-lines along with spared,
normal A-lines, also known as skip areas.
"Patchy B-lines and confluent B-lines," he said. "That's a pattern that we are seeing
commonly in many of the images that have been sent to us over the last several
weeks."
In addition, the ultrasound scans of patients with COVID-19 show a thickened
pleural line. Patients can also have subpleural consolidation or traditional
consolidation.
"You've got an area of almost solid organ-appearing tissue under the pleural line,"
Stone said. "You've got some air bronchograms. This isn't dissimilar from what you
might see in bacterial pneumonia."
In COVID-19 patients, the findings also fluctuate and reoccur, as they did for Chen.
Patients can have A-lines disappear, reappear a few days later, and then disappear
again. Pleural consolidation can also wax and wane, according to Stone.

3. Ultrasound for triage
Stone polled lung ultrasound experts in his network to see how doctors in Spain,
Italy, and other countries have used ultrasound systems to triage patients. While he
cautioned that no doctor should be making admission or discharge decisions based
solely on ultrasound scan findings, the doctors used ultrasound in similar ways.
For areas where rapid PCR testing is available, a patient with hypoxia and a positive
SARS-CoV-2 PCR test is often admitted to the hospital's COVID-19 unit, with
imaging left to the discretion of the treating provider.
"What I've heard repeatedly from physicians hardest hit in Italy is that in the COVID
wards, when they make rounds, they'll come in and they'll scan their lungs," Stone
said. "They'll scan their heart, looking for cardiac issues. They'll scan the [inferior
vena cava] collapsibility to take care of all three of those assessments at one time
with the single physician."
In areas where rapid PCR testing isn't available or where tests are running low, lung
ultrasound is sometimes used as a secondary screening modality after patient
presentation and COVID-19 risk factors.
For instance, Stone doesn't have access to rapid PCR testing, so he has been using
ultrasound for patients with labored breathing.
"That's my trigger," he said. "Even if their oxygen saturations are normal, if they're
feeling short of breath, I want to take a look at their lungs. That's how I'm making
that decision right now."
Similarly, when Chen's wife complained of mild throat soreness a few days ago, he
couldn't get access to a PCR test. So he scanned her back with POCUS instead.
"There were B-lines with the thickened pleura," he said. "I didn't need to do anything
else. That was the positive result that I was waiting for."
Some patients who appear healthy can also have "ugly" ultrasound scan results.
And while clinical symptoms, including hypoxia, tachycardia, and dyspnea, can lag
behind ultrasound findings, that doesn't mean every patient with concerning
ultrasound results needs to be admitted.
"Admission decisions are going to be based on patients who are tremendously ill,"
he said. "People with hypoxia, people with increased work of breathing who look
unwell -- those patients are going to be coming in kind of regardless of what their
lung ultrasound shows."
Too soon?

4. Stone stressed that there hasn't been time to do the kind of evidence-based,
prospective studies the medical profession relies on. So, some of these
recommendations will be quickly outdated.
Stone is collecting data based on his own experiences and those of other doctors
using all types of ultrasound imaging systems in the fight against COVID-19. And so
far, it's looking like lung ultrasonography may be a helpful tool -- and it's not hard to
learn.
"The good news is that lung ultrasound -- as opposed to say echocardiography -- is
really easily learned," he said. "The lung surface is very accessible. There aren't
these tiny windows to work with. I have taught completely naive people how to look
for lung sliding, A-lines, and B-lines successfully in less than a 30- or 40-minute
session. So this is not challenging to learn.
Lung ultrasound identifies patients with COVID-19.
By Theresa Pablos, AuntMinnie staff writer
March 27, 2020 -- Researchers from Italy have created protocols for performing lung
ultrasonography on patients with COVID-19. Their list of four brief acquisition
protocols was published in a clinical letter on March 20 in the Journal of Ultrasound
in Medicine.
The protocols outline the best probe to use, where clinicians should look for artifacts,
where to set the focus, and how to visualize the widest surface possible with one
scan. The authors reported that hospital staff in Germany have asked to implement
the protocols and that they are training doctors in Rome on their techniques.
"For the first time, the scientific validity of the technique we proposed is accepted,"
stated Paolo Giorgini, PhD, director of a computer science laboratory at the
University of Trento that helped come up with the protocols. "We hope our work can
help tackle the pandemic."
While CT has excellent ability to detect COVID-19, the modality can't be used at
patients' bedsides and it puts additional medical staff at risk for virus exposure. As a
result, some doctors in China, Spain, and Italy have turned to lung ultrasound as an
alternative imaging modality.
Patients with COVID-19 develop thickened pleura, B-lines, subpleural
consolidations, and other hallmark lung ultrasound artifacts that can help doctors
identify and track the progression of the disease. However, given limited time and

5. resources, there haven't been many publications that clarify how to best use lung
ultrasound to make a diagnosis of COVID-19 and guide patient treatment.
In the absence of other research on the topic, lead author Dr. Gino Soldati from the
ultrasound unit at Valle del Serchio General Hospital in Lucca, Italy, and colleagues
developed their own guidelines. Their set of four acquisition protocols for lung
ultrasonography on patients with COVID-19 is as follows:

6. 1.Ideally, use linear probes, as these can best capture the detail of pleural and
subpleural artifacts. Convex probes are also appropriate.
2.Use a single focal point modality at the pleural line instead of focusing at
multiple locations.
3.Scans should preferably be performed in intercostal spaces, as opposed to an
orthogonal view of the ribs. This enables clinicians to see the widest surface
possible with one scan.
4.Look for artifacts in multiple areas and bilaterally to see the extent of the
affected lung surface.
Specifically, the authors recommended looking for artifacts in the following areas on
both the right and left sides of patients:
 Anterior midclavicular: apical, medial, and basal
 Posterior paraspinal: apical, medial, and basal
 Lateral axillary: apical and basal
The researchers also mentioned that lung ultrasound can be used for triaging
patients before hospital admission, monitoring emergency department patients with
pneumonia, managing ventilation and weaning for intensive care unit patients, and
evaluating the effects of antiviral medications. This is because ultrasound can
identify changes in the ratio between air, tissue, and fluid in the lungs of patients
with COVID-19.
The authors cautioned their protocol is only a suggestion and that more studies will
be needed to confirm their findings -- especially research that compares lung
ultrasound scans to other imaging modalities.
"Comparison with chest x-ray and/or lung CT scan might help [in] designing a proper
diagnostic workup according to the general and local technological and human
resources," they concluded.