London, June 1 (IANS): Researchers have reported high incidence of deep vein thrombosis in patients with severe Covid-19 in an intensive care unit in France.

This may indicate the need for systematic anticoagulant therapy in these patients as a preventive measure, said researchers from Centre Cardiologique du Nord, Saint-Denis, France.

A common type of venous thrombosis is a deep vein thrombosis (DVT), which is a blood clot in the deep veins of the leg.

For the findings, published in the JAMA Network Open, a total of 34 consecutive patients were included for the tests.

Patients with severe Covid-19 pneumonia were admitted to the ICU located in the suburban Paris area from mid-March 2020 to the beginning of April 2020.

All patients had acute respiratory distress syndrome, according to the Berlin definition and required mechanical ventilation.

Of the 34 patients, 65 per cent had deep vein thrombosis at the time of admission, and in another five patients, bringing the total up to (79 per cent), at the time of repeat venous ultrasound.

In 18 of the patients or over 50 per cent, bilateral deep vein clots were found to be present.

The study also showed that in a quarter of patients, the clot was within the veins nearer the heart.

According to the researchers, among the 15 patients with diabetes in total, for instance, 12 developed deep vein thrombosis.

Similarly, for the 13 patients with hypertension, nine developed thrombosis.

The findings showed a higher white cell count, lymphocyte count, and platelet count in peripheral blood in the patients who developed deep vein thrombosis compared to the other group.

"This case series reports a systematic assessment of deep vein thrombosis among patients in an intensive care unit (ICU) in France with severe COVID-19," the authors wrote.