Assistant Professor and International Collaborators Publish Recommendations for Thromboprophylaxis in Pregnant Patients with COVID-19

Written by Dr. Rohan D'Souza, Primary Author and Assistant Professor with the University of Toronto's Department of Obstetrics and Gynaecology.

Patients with COVID-19 are at an increased risk for developing blood clots. It has therefore been suggested that these patients, especially if hospitalized, should receive prophylactic doses of blood thinners to prevent the development of clots. However, despite the use of prophylactic doses of blood thinners, many hospitalized patients continue to develop blood clots, not only in their leg veins but also in their lungs, prompting a debate on whether hospitalized patients with COVID-19 should be given higher (therapeutic) doses of blood thinners. Pregnant persons are already at an increased risk for developing blood clots, and therefore this debate is very pertinent to those that care for pregnant persons.

In this review written with an international group of collaborators representing seven universities in five countries, including world experts Prof. Beverley Hunt OBE FRCP FRCPath (United Kingdom) and Prof Claire McLintock ONZM MBChB, FRACP, FRCPA (New Zealand), the review explores the origin and nature of blood clots in patients with COVID-19, and describes that these occur as a result of at least two distinct mechanisms, only one of which might respond to blood thinners. The other mechanism, which is the product of intense inflammation in the lungs (immunothrombosis), is unlikely to respond to increased doses of blood thinners, but might put patients at increased risk for bleeding complications.

Experimental treatments that reduce inflammation (anti-cytokines) and the viral load (antivirals) could potentially be used to reduce the risk of blood clots from immunothrombosis. However, these treatments should only be administered within the context of research studies and under close supervision.

For now, when managing pregnant persons with COVID-19, there is no role for routinely using high (therapeutic) doses of blood thinners or aspirin. Decisions on the dose and duration of blood thinners need to be made by a multidisciplinary team that includes high-risk obstetricians, haematologists, internists and/or intensivist, and should consider four important aspects:

• the severity of the disease;
• whether the person is hospitalized or self-isolating at home;
• the timing of disease onset in relation to childbirth; and,
• pre-existing medical/ genetic conditions that put the person at an increased risk for developing blood clots.

An algorithm that takes these factors into account are presented in this review article and will help guide clinicians caring for pregnant persons with COVID-19. Read the full publication here.

_____________________________________________________________

Don't want to miss a post? Follow us on social media for more news!

FACEBOOK | INSTAGRAM | TWITTER

If you would like to be a guest blogger, please contact us at obgyn@utoronto.ca.