We are often asked to assist in the management of sick patients in ICU, as many of these patients can develop complications in their blood system. In sick patients – due to either severe infections, surgical complications or even trauma, imbalances in their blood clotting can often lead to issues with either bleeding or clotting disorders.

What has become apparent in the SAR-COVID-19 pandemic is that many patients with severe disease are developing severe abnormalities with their clotting. It has been observed that many of these patients has a significantly raised level of a blood marker known as D-dimer which often indicates the activation of clotting in the body.

More than 30% of patients with moderate to severe SAR-COVID-19 infections have been noted to have pulmonary emboli (blood clots in the lungs), and doctors have also observed clots in other organs such as the brain (leading to strokes), and heart (leading to heart attacks), sometimes in young adults.

There are several theories as to why this is happening. One thought is that the virus is causing damage to the lining of blood vessels (endothelial damage), as this damage triggers the formation of clots. Another theory is that the infection caused by the virus can also provoke a severe inflammatory response with release of a lot of different chemicals into the body (cytokines), and this process stimulates the formation of clots throughout the body.

Doctors in different countries have started to use blood thinners early in the management of SAR-COVID-19 patients to see if the formation of blood clots can be prevented. At present, it is not clear if this approach is as effective as hoped, and there is also the risk of patients developing bleeding if they are too actively managed with blood thinners.

A lot more research and findings will be forthcoming in the next few months as doctors and scientists rush to find out why SAR-COVID-19 patients are developing such clotting problems and hopefully early interventions will be formulated to avoid organ damage in their patients.