BACKGROUND The risk of major venous thromboembolism (VTE) among patients with COVID-19 is high but varies with disease severity.

OBJECTIVE Estimate the incidence of lower extremity deep venous thrombosis (DVT) in critically ill hospitalized patients with COVID-19, validate the Wells score for DVT diagnosis, and determine patient’s prognosis.

DESIGN AND SETTING This was an observational follow-up study in the context of diagnosis and prognosis of DVT. All patients hospitalized in the intensive care unit (ICU) of the Evandro Chagas National Institute of Infectious Diseases.

METHODS Participants with COVID-19 pneumonia were included. Lower-limb Doppler to assess DVT was performed at admission and follow-up. Prognosis outcomes were death, length of stay, need for mechanical ventilation, vasopressor use, and hemodialysis. Wells’ score sensitivity and specificity were estimated at admission. Survival curves were estimated for patients with DVT and adjusted for the SAPS3 score.

RESULTS Between June 2020 and January 2021, 186 patients were included. The DVT incidence was 0.097. A Wells score of two or higher had a sensitivity and specificity of 1.00 and 0.94 respectively. Mortality and mechanical ventilation support were higher in participants with DVT. For these outcomes, after SAPS 3 adjustment, participants with DVT had twice the hazard of those without DVT. A web calculator (https://pedrobrasil.shinyapps.io/INDWELL/) is available for predictions.

CONCLUSIONS One can use the Wells score to accurately diagnose DVT in critically ill patients with COVID-19. DVT increases severity of COVID-19, which highlights the importance of its early diagnosis, treatment, and prophylaxis at the ICU setting.

The authors have declared no competing interest.

The RECOVER-SUS study was partly supported by funding from Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro [grants E26/202.915/2018, E-26/201.351/2021 and E-26/210.820/2021], from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) [grant 305789/2019-8] and from Programa INOVA-FIOCRUZ [Geração de Conhecimento. INI-FIOCRUZ has a hospital area made up of wards, isolation rooms, and intensive care units fully structured to receive patients with infectious diseases. This hospital unit was expanded to face the COVID-19 Pandemic and Post-Pandemic grant number VPPCB-005-FIO-2]

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

All participants or their legal representatives signed an informed consent form before enrollment in RECOVER-SUS-BRASIL. The deep vein thrombosis sub-study protocol was approved by the Ethics Committee Instituto Nacional de Infectologia Evandro Chagas - Fundação Oswaldo Cruz on October 9th, 2020, and can be found at https://plataformabrasil.saude.gov.br/visao/publico/indexPublico.jsf with the number CAEE 32449420.4.1001.5262.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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Sources of funding: The RECOVER-SUS study was partly supported by funding from Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro [grants E26/202.915/2018, E-26/201.351/2021 and E-26/210.820/2021], from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) [grant 305789/2019-8] and from Programa INOVA-FIOCRUZ [Geração de Conhecimento. INI-Fiocruz has a hospital area made up of wards, isolation rooms and intensive care units fully structured to receive patients with infectious diseases. This hospital unit was expanded to face the COVID-19 Pandemic and Post-Pandemic grant number VPPCB-005-FIO-2]

Conflict of interest: The authors have no competing interests to declare.

Data may be available from the corresponding author upon reasonable request.