What findings should I look for in the chest imaging of my patients with the novel Coronavirus disease/Covid-19?

Chest imaging is often obtained to evaluate for pneumonia and progressive lung injury due to Covid-19. Given the concerns over healthcare worker exposure and environmental contamination, radiographic imaging should be minimized and obtained only when clinically indicated (1).

 
Routine chest radiograph: In a study involving over 1000 hospitalized patients with Covid-19, chest Xray abnormalities on admission were observed in about half of patients with nonsevere disease and three-quarters of those with severe disease (2). Many infiltrates are bilateral, patchy and peripheral in distribution (2,3).

 
Chest CT (without IV contrast):  CT abnormalities on admission have been observed in 84% of patients with nonsevere and 94% of patients with severe disease (2). Ground glass opacities (GGOs) and consolidation have been reported in the majority of patients. Infiltrates are often bilateral, peripheral, and posterior in distribution ( 2-5).

Compared to other causes of pneumonia, the most discriminating features of Covid-19 pneumonia on CT include peripheral distribution of infiltrates (80% vs 57%) and GGOs (91% vs 68%) (5).

CT findings are time dependent. Early during the course of infection, peripheral focal or bilateral multifocal GGOs are frequently observed, later giving rise to “crazy paving” and consolidation with occasional “reverse halo sign” as the disease progresses (see Bonus Pearl below), peaking around 9-13 days (6,7) . Pleural effusion and lymphadenopathy are uncommon (5,7).

 
Point of care ultrasound (POCUS): This relative newcomer offers a potentially useful and rapid means of evaluating for pneumonia or lung injury in Covid-19 and may be more sensitive than chest Xray. Its findings are not specific for Covid-19 lung pathology, however. In a preliminary report involving 12 patients with Covid-19 pneumonia (without ARDS) who underwent POCUS, a diffuse B-line pattern with spared areas was seen in all patients (8,9). Strict adherence to proper isolation precautions and decontamination of the ultrasound probe are essential.

 

Bonus Pearl: “Crazy paving” pattern on CT refers to GGOs with superimposed interlobular septal thickening and intralobular septal thickening, while “reversed halo sign” is a central GGO surrounded by denser consolidation of crescentic shape ring at least 2 mm in thickness (reference 7 has nice photos).

 

Liked this post? Download the app on your smart phone and sign up below to catch future pearls right into your inbox, all for free!

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

 

References
1. ACR recommendations for the use of chest radiography and computed tomography (CT) for suspected COVID-19 infection. March 19, 2020. https://www.acr.org/Advocacy-and-Economics/ACR-Position-Statements/Recommendations-for-Chest-Radiography-and-CT-for-Suspected-COVID19-Infection
2. Guan WJ, Zheng-yi N, Hu Y, et al. Clinical characteristics of Coronavirus disease 2019 in China. N Engl J Med 2020; February 28. https://www.nejm.org/doi/full/10.1056/NEJMoa2002032
3. Ai T, Yang Z, Hou H, et al. Correlation of chest CT and RT-PCR testing in Coronavirus disease 2019 (COVID-19) in China: A report of 1014 cases. Radiology 2020. https://pubs.rsna.org/doi/10.1148/radiol.2020200642
4. Yoon SH, Lee KH, Kim JY, et al. Chest radiographic and CT findings of the 2019 Novel Coronavirus disease (COVID-19): Analysis of nine patients treated in Korea. Korean J Radiol 2020;21 :494-500. https://www.kjronline.org/Synapse/Data/PDFData/0068KJR/kjr-21-494.pdf
5. Bai HX, Hsieh B, Xiong Z, et al. Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT. https://pubs.rsna.org/doi/10.1148/radiol.2020200823
6. Kanne JP, Little BP, Chung JH, et al. Essentials for radiologists on COVID-19: An update—Radiology scientific expert panel. Radiology 2020; February 27. https://pubs.rsna.org/doi/10.1148/radiol.2020200527

7. Bernheim A, Mei X, Huang M, et al. Chest CT findings in Coronavirus Disease-19 (COVID-19):Relations to duration of infection. Radiology 2020 Feb 20:200463.  https://pubs.rsna.org/doi/pdf/10.1148/radiol.2020200463
8. Poggiali E, Dacrema A, Bastoni D, et al. Can lung US help critical care clinicians in the early diagnosis of novel Coronavirus (COVID-19) pneumonia? Radiology 2020; https://www.ncbi.nlm.nih.gov/pubmed/32167853

9. Peng QY, Wang XT, Zhang LN, et al. Findings of lung ultrasonography of novel Coronavirus pneumonia during the 2019-2020 epidemic. Intensive Care Med 2020. https://doi.org/10.1007/s00134-020-05996.

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Massachusetts General Hospital, Harvard Catalyst, Harvard University, its affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

What findings should I look for in the chest imaging of my patients with the novel Coronavirus disease/Covid-19?

Key clinical pearls in the medical management of hospitalized patients with coronavirus (Covid-19) infection

First, a shout-out to dedicated healthcare workers everywhere who have selflessly given of themselves to care for the sick during this pandemic. Thank you! Together, I know we will get through it!

Although our understanding of Covid-19 infection is far from complete, in the spirit of clarity and brevity of my posts on Pearls4Peers, here are some key points I have gleaned from review of existing literature and the CDC that may be useful as we care for our hospitalized patients with suspected or confirmed Covid-19 infection.

  • Isolation precautions.1 Per CDC, follow a combination of airborne (particularly when aerosol generating procedures is anticipated, including nebulizer treatment) and contact precaution protocols. Routinely use masks or respirators, such as N-95s (subject to local availability and policy) and eye protection. Don gowns (subject to local availability and policy) and gloves and adhere to strict hand hygiene practices.

 

  • Diagnostic tests1-9
    • Laboratory tests. Routine admission labs include CBC, electrolytes, coagulation panels and liver and renal tests. Other frequently reported labs include LDH, C-reactive protein (CRP) and procalcitonin. Testing for high sensitivity troponin I has also been performed in some patients, presumably due to concern over ischemic cardiac injury or myocarditis.2 Check other labs as clinically indicated.
    • Chest radiograph/CT chest. One or both have been obtained in virtually all reported cases with CT having higher sensitivity for detection of lung abnormalities.
    • EKG. Frequency of checking EKGs not reported in many published reports thought 1 study reported “acute cardiac injury” in some patients, based in part on EKG findings.4 Suspect we will be checking EKGs in many patients, particularly those who are older or are at risk of heart disease.
    • Point-of-care ultrasound (POCUS). This relatively new technology appears promising in Covid-19 infections, including in rapid assessment of the severity of pneumonia or ARDS at presentation and tracking the evolution of the disease. 9 Don’t forget to disinfect the probe between uses!

 

  • Treatment 1-8
    • Specific therapies are not currently available for treatment of Covid-19 infections, but studies are underway.
    • Supportive care includes IV fluids, 02 supplementation and nutrition, as needed. Plenty of emotional support for patients and their families will likely be needed during these times.
    • Antibiotics have been used in the majority of reported cases, either on admission or during hospitalization when superimposed bacterial pneumonia or sepsis could not be excluded.
      • Prescribe antibiotics against common community-acquired pneumonia (CAP) pathogens, including those associated with post-viral/influenza pneumonia such as Streptococcus pneumoniae (eg, ceftriaxone), and Staphylococcus aureus (eg, vancomycin or linezolid if MRSA is suspected) when concurrent CAP is suspected.
      • Prescribe antibiotics against common hospital-acquired pneumonia (HAP) (eg, vancomycin plus cefepime) when HAP is suspected.
    • Corticosteroids should be avoided because of the potential for prolonging viral replication, unless indicated for other reasons such as COPD exacerbation or septic shock. 1
    • Monitor for deterioration in clinical status even when your hospitalized patient has relatively minor symptoms. This is because progression to lower respiratory tract disease due to Covid-19 often develops during the 2nd week of illness (average 9 days).
    • ICU transfer may be necessary in up to 30% of hospitalized patients due to complications such as ARDS, secondary infections, and multi-organ failure.

 

Again, thank you for caring for the sick and be safe! Feel free to leave comments or questions.

 

 Liked this post? Download the app on your smart phone and sign up below to catch future pearls right into your inbox, all for free!

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

 

References

  1. CDC. Interim clinical guidance for management of patients with confirmed coronavirus disease (COVID-19). https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-guidance-management-patients.html
  2. Ruan Q, Yang K, Wang W, Jiang L, et al. Clinical predictors of mortality due to COVID-19 based on analysis of data of 150 patients with Wuhan, China. Intensive Care Med 2020. https://link.springer.com/article/10.1007/s00134-020-05991-x
  3. Holshue ML, BeBohlt C, Lindquist S, et al. First case of 2019 novel coronavirus in the United States. N Engl J Med 2020;382:929-36. https://www.nejm.org/doi/full/10.1056/NEJMoa2001191
  4. Huang C, Wang Y, Li Xingwang, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet 2020;395:497-506. https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(20)30183-5.pdf
  5. Young BE, Ong SWX, Kalimuddin S, et al. Epideomiologic features and clinical course of patients infected with SARS-CoV-2 Singapore. JAMA, March 3, 2020. Doi.10.1001/jama.2020.3204 https://www.ncbi.nlm.nih.gov/pubmed/32125362
  6. Chen N, Zhou M, Dong X, et al. Epidemiological and clinical chacteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet 2020;395:507-13. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30211-7/fulltext
  7. Guan W, Ni Z, Hu Y, et al. Clinical characteristics of coronavirus disease 2019 in China. N Engl Med 2020, Feb 28, 2020. https://www.nejm.org/doi/full/10.1056/NEJMoa2002032
  8. Zhang J, Zhou L, Yang Y, et al. Therapeutic and triage strategies for 2019 novel coronavirus disease in fever clinics. Lancet 2020;8: e11-e12. https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30071-0/fulltext 9.
  9. Peng QY, Wang XT, Zhang LN, et al. Findings of lung ultrasonography of novel corona virus pneumonia during the 2019-2020 epidemic. Intensive Care Med 2020. https://doi.org/10.1007/s00134-020-05996-
Key clinical pearls in the medical management of hospitalized patients with coronavirus (Covid-19) infection