Outcomes of Vascular Surgery in COVID-19 Infection: National Cohort Study

To determine 30-day mortality in patients with COVID-19 infection who undergo vascular
surgery.

This will inform future risk stratification, decision making, and patient consent.

Inclusion criteria

The inclusion criteria are:

• Adults (age ≥18 years) undergoing ANY type of vascular surgery in an operating theatre,
this includes open surgery, endovascular surgery or hybrid procedures.

AND

• Either before or after surgery: (i) lab test confirmed COVID-19 infection or (ii) clinical
diagnosis of COVID-19 infection (no test performed).

Therefore this study should capture:

- emergency surgery patients with clinical diagnosis or lab confirmation of COVID-19
infection before surgery.

- emergency surgery patients with clinical diagnosis or lab confirmation of COVID-19
infection after surgery.

- elective surgery patients with clinical diagnosis or lab confirmation of COVID-19
infection after surgery. Patients who meet the inclusion criteria should be included
regardless of surgical indication (aneurysm, limb or visceral ischemia, carotid
stenosis, vascular trauma), anaesthetic type (local, regional, general), procedure type,
or surgical approach (open surgery, endovascular surgery, hybrid procedure).

At most sites it is anticipated that the number of eligible patients is likely to be low. If
possible all consecutive patients fulfilling inclusion criteria should be entered.

Study period Overall we plan to close data entry in September 2020 when the global pandemic
is likely to be over, however individual centres may select their own study windows,
depending on the timing of COVID-19 epidemic in their community.

Patient enrolment Ideally patients should be identified prospectively. However, given the
rapid progression of the global pandemic, there may be no further new cases of COVID-19
infection in some hospitals that treated large numbers of COVID-19 earlier in the pandemic.
It is important to capture the experience of these centres, therefore retrospective patient
identification and data entry is permitted.

Primary outcome

- 30-day mortality Secondary outcome

- 7-day mortality

- 30-day reoperation

- Postoperative ICU admission

- Postoperative respiratory failure

- Postoperative acute respiratory distress syndrome (ARDS)

- Postoperative sepsis

Data collection Data will be collected and stored online through a secure server running the
Spanish Society for Angiology and Vascular Surgery (SEACV) web application. This secure
server allows collaborators to enter and store data in a secure system. A designated
collaborator at each participating site will be provided with a project server login details,
allowing them to securely submit data on to the system. Only anonymised data will be uploaded
to the database. No patient identifiable data will be collected. Data collected will be on
comorbidities, physiological state, treatment/operation, and outcome. No dates (e.g. date of
surgery) will be collected. qSOFA and CURB-65 will be calculated based on the individual data
points entered.

Local approvals The principal investigator at each participating site is responsible for
obtaining necessary local approvals (e.g. research ethics committee or institutional review
board approvals).The first approval will be on the Valladolid East Ethics Committee for
Clinical Investigation.

Collaborators will be required to confirm that a local approval is in place at the time of
uploading each patient record to the study database.

Where an audit approval is needed, this can be either registered as service evaluation, or to
benchmark against an auditable standard (e.g. overall mortality after emergency surgery
should be <15%).

Prior to formal local study approval, collaborators may prospectively collect data, but this
should not be uploaded to the database until approval is confirmed.

Analysis A detailed statistical analysis plan will be written. Analyses will be overseen by
the independent data monitoring committee (DMC). Reports will include description of the
primary and secondary outcomes in the cohort. Multivariable modelling will be undertaken to
CovidVAS protocol identify risk factors for 30-days mortality. Analyses will be stratified
according to whether or not diagnosis of COVID-19 was confirmed by a lab test. Interim
analyses will be performed as guided by the independent DMC. The first analysis will be
performed once 50 patients have been entered on to the database, and the frequency of
subsequent analyses will be agreed with the DMC. The decision to submit data for publication
will be agreed by the steering committee with the DMC. Hospital-level data will not be
released or published.

Authorship Collaborators from each site who contribute patients will be recognised on any
resulting publications as PubMed-citable co-authors.