Clinical Ultrasound in Covid-19

Site: ISRRT e-Learning
Course: Practical guidelines for radiographers/radiological technologists during the pandemic COVID-19
Book: Clinical Ultrasound in Covid-19
Printed by: Guest user
Date: Thursday, 28 October 2021, 12:15 AM

Description

Ultrasound can be used in the assessment of lung, but also for determining if the patient has a deep vein thrombosis (DVT).

This section will provide resources to support your learning in these two areas. 


1. Lung ultrasound

Introduction:

Literature has suggested that lung ultrasound can be used in assessment of Covid-19 patients. It is important to know what you are looking for and how to perform the technique, before scanning patients in the clinical setting. Adequate audit of findings is also essential to ensure accurate diagnosis and on-going competency. 


1.1. Introduction

Lung ultrasound may be requested for covid-19 patients, although some research has suggested there is a lower sensitivity, but high specificity. The resources in this section are to help you get a better understanding of the technique and ultrasound appearances of the lung with ultrasound. Again, if you are using ultrasound to assess the lung within your clinical practice you must be competent to do this. 

There are a number of different techniques within the literature for assessing the whole of the thoracic cavity. Which ever method you select, it is important to scan the lung fields in a systematic way to cover all aspects. 

Normal lung moves with respiration, known as 'lung sliding'. It would be good practice to learn the appearances of normal healthy lung before starting to scan symptomatic and / or complex cases. 

Common findings in abnormal lung in a Covid-19 positive patient include:

  • B-lines
  • Subpleural consolidation
  • Consolidation with air bronchogram


Remember 
Ultrasound examinations should only be carried out by a competent and trained health care professional, with appropriate audit to ensure safe, competent on-going practice. 


1.2. YouTube video 1

Watch the following YouTube video to learn more about the technique for lung ultrasound

https://youtu.be/EQtzCVMC_Dk 

1.3. YouTube video 2

European Association of Cardiovascular Imaging video showing the technique, equipment settings, appearances and pitfalls of lung ultrasound. 

Case Studies and images showing ultrasound and CT comparison. 


1.4. Lung ultrasound article and animation

Review the following article and images below, to get a better understanding of the evidence for using lung ultrasound.

Smith, M.J., Hayward, S.A., Innes, S.M. and Miller, A.S.C. (2020), Point‐of‐care lung ultrasound in patients with COVID ‐19 – a narrative review. Anaesthesia. doi:10.1111/anae.15082

Smith et al gif


smith et al jpeg

Shared with permission & (cc) licence. 

1.5. Additional resources

There are a number of resources available on lung ultrasound. Some are specific to covid-19, others are more general articles. A range of suggestions are provided here.

British Medical ULtrasound Society (BMUS) (2020) Lung Ultrasound. https://www.bmus.org/static/uploads/resources/COVID19__Lung_Ultrasound_BMUS.pdf

Gargani, L., & Volpicelli, G. (2014). How I do it: lung ultrasound. Cardiovascular ultrasound12, 25. https://doi.org/10.1186/1476-7120-12-25

The POCUS atlas http://www.thepocusatlas.com/pulmonary

Soldati G., Smargiassi A., Inchingolo R. et al (2020). Is there a role for lung ultrasound during the COVID-19 pandemic? Journal of Ultrasound in Medicine  DOI:10.1002/ jum.15284 https://onlinelibrary.wiley.com/doi/epdf/10.1002/jum.15284

2. Leg ultrasound for DVT

As Covid-19 can cause hyper-coagulation in some severe and critical cases (Klok et al, 2020; Levi et al, 2020) you might be asked to scan a patient for suspected deep vein thrombosis (DVT). Before undertaking such an examination you need to make sure you have the appropriate skills and competency to do this. The research is still unclear and there are theories that potentially the pulmonary clots develop within the lungs rather than being embolitic in nature. Patients often have high D-dimer levels and other markers (Zhou et al 2020). 

Depending on the circumstances you may be able to complete a full examination of the limb including compression, colour Doppler +/- spectral Doppler. If resources are limited or the patient is in intensive care and difficult to scan a more focused assessment may be required. This will have limitations and it should be recognised in the report. 

This section contains basic resources about ultrasound assessment for DVT. 

Equipment needed:

  • Real-time ultrasound machine
  • Pulse wave Doppler
  • Colour Doppler
Techniques:

  • B-mode ultrasound of the deep veins of the limb
  • Compression, to determine whether the vessel collapses completely (used with care/excluded if thrombus is seen within the vessel)
  • Pulse wave Doppler and Valsalva technique
  • Colour Doppler to assess filling of the vessel.

Other considerations:

  • Appropriate PPE
  • Sterile gel sachets
  • Possible probe cover
  • Preparation of the machine
  • Decontamination following the examination using manufacturer approved processes.


Remember 
Ultrasound examinations should only be carried out by a competent and trained health care professional, with appropriate audit to ensure safe, competent on-going practice. 


References:

Klok, F. A., Kruip, M., van der Meer, N., Arbous, M. S., Gommers, D., Kant, K. M., Kaptein, F., van Paassen, J., Stals, M., Huisman, M. V., & Endeman, H. (2020). Incidence of thrombotic complications in critically ill ICU patients with COVID-19. Thrombosis research, S0049-3848(20)30120-1. Advance online publication. https://doi.org/10.1016/j.thromres.2020.04.013

Levi, M., Thachil, J., Iba, T., Levy, J. (2020) Coagulation abnormalities and thrombosis in patients with COVID-19. The Lancet Haematology, 0 (0) doi:10.1016/S2352-3026(20)30145-9. Available at: https://www.thelancet.com/journals/lanhae/article/PIIS2352-3026(20)30145-9/fulltext

Zhou, F., Yu, T., Du, R., et al. (2020) Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. LancetS0140-6736 (20)30566-3. Available at: https://www.sciencedirect.com/science/article/pii/S0140673620305663


2.1. Guidance for DVT (non-Covid-19)

Reporting DVT examinations

Advice recommends that the term 'superficial femoral vein' is not used within the clinical report, to avoid confusion, as this is a deep vein. The conclusion should clearly state that a deep vein thrombosis is present, if  one is detected during the examination. https://www.sor.org/news/guidance-use-term-superficial-femoral-vein


Guidance on diagnosis and management of venous thromboembolism: 

National Institute for Health and Care Excellence [NICE] (2000) Venous thromboembolism: diagnosis and anticoagulation treatment. Visual summary. Available at: https://www.nice.org.uk/guidance/ng158/resources/visual-summary-pdf-8709091453

NICE (2000) Venous thromboembolic diseases: diagnosis, management and thrombophilia testing. NICE guideline [NG158]. Available at: https://www.nice.org.uk/guidance/NG158


Background information on venous-thromboembolisatim can be found on the e-learning for healthcare site (free to register for this module). https://www.e-lfh.org.uk/programmes/venous-thromboembolism/

2.2. YouTube video 1: Normal technique


2.3. YouTube video 2: technique and pathology

2.4. YouTube video 3: pathology and pitfalls


2.5. Additional resources

Katz, et al (2014) Imaging of deep venous thrombosis: A multimodality overview. Applied RadiologyMarch 05. Available at: https://appliedradiology.com/articles/imaging-of-deep-venous-thrombosis-a-multimodality-overview

Needleman et al (2018) Ultrasound for Lower Extremity Deep Venous Thrombosis. 

Multidisciplinary Recommendations From the Society of Radiologists in Ultrasound Consensus Conference. Circulation, 137 (14), 1505-1515. Available at: https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.117.030687