PB1337 - Changing Pattern of Venous Thrombosis events in 2021 associated with COVID in a teaching hospital

Background: University Hospitals Plymouth, NHS trust, is a teaching hospital which has been a venous thromboembolism (VTE) exemplar centre since 2010. Data on VTE events, whether hospital acquired (HAT) and radiology scans performed, has been collected since 2010.

Aims: To review whether COVID had an impact on number of VTE events diagnosed, number of HAT events and radiological investigations performed.

Methods: Collect VTE outcome data from computed tomography pulmonary angiography (CTPA), ventilation perfusion scans (V/Q) and Doppler ultrasounds of upper and lower limbs. Review positive VTE events as to whether they meet criteria for HAT and compare outcome data for 2021 with an average from 2010 - 2020.

Results: In 2021 number of VTE events was 944, an increase of 153 (19%) over previous 11 years. HAT events were 206, increased by 17 (9%) though as a percentage of total VTE fell from 24% to 22%. Total pulmonary embolism (PE) was 590, increase of 136 (30%), although deep vein thrombosis (DVT) events were 354, representing an increase of 18 (5%). CTPA scans rose by 891 (41%) to 7021 though DUS remained similar with 2714 scans against an average of 2704 and VQ scans reduced to 339 compared with 545. Of the positive VTE events, 72 (8%) were associated with a COVID diagnosis and a significant number 67 (93%) being PE compared to 5 (7%) DVT.

Conclusion(s): There is likely to be an association between VTE increase and shielding as well as positive COVID events causing a decrease in usual physical activity. It is not entirely clear why PE increased significantly but as COVID is a respiratory virus and causes significant inflammation within the lungs, this may have impacted on these figures. Initial review of data confirms no significant changes to VTE risk factors. We will continue to collect and monitor this data in 2022.