Retrospective Study of Patients with Upper Extremity Clots Presenting to Emergency Departments in Tertiary Care Hospitals in a Major Canadian City in the Last Five Years

Objective: 5 year retrospective study of patients presenting to emergency departments at the four tertiary care hospitals in Calgary, Alberta with upper extremity (UE) deep vein thrombosis (DVT) to define the patient population, determine practice patterns and management of upper extremity clots.

Methods: All adult patients with suspected upper extremity DVT presenting to any of the four tertiary care centers in the Calgary health region and who had undergone diagnostic imaging were included in the study. Ultrasounds and CT scans were obtained from the Diagnostic Imaging department from January 2014 to December 2018. Inclusion criteria included patients above 18 years of age and evidence of deep, superficial or catheter-associated upper extremity venous thrombosis on imaging. Exclusion criteria were any known cancer or life expectancy under 6 months. Basic demographic data were collected, in addition to disposition from emergency, choice of anticoagulant, duration of anticoagulation, history of thrombophilia and thoracic outlet obstruction (TOO) work-up.

Results: 1236 patient records were reviewed, of which 151 (12.2%) were positive for UE deep venous thrombosis (DVT) and 114 (9.2%) for superficial vein thrombosis (SVT). Mean age was 47 years and 50.2% were males. Duration of treatment for both DVT and SVT ranged anywhere from no therapy to lifelong treatment, with an average of 5.01 months for DVT and 1.15 months for SVT. 22.5% of all DVTs were recommended lifelong therapy. 21 (18.4%) patients were treated for more than 45 days for SVT, of which only 9 had another indication for anticoagulation. Common risk factors identified for DVT included line associated thrombosis (17.2%), of which 38.5% were specifically PICC associated, trauma (2.6%) and intravenous drug use (2.0%). Anticoagulant agents for DVT included low molecular weight heparin (7.9%), direct oral anticoagulants (DOACs) (39.1%) and warfarin (42.4%). 8.6% of the DVTs received no treatment. Follow-up was variable from the emergency department ranging from following up with the patient's own family physician to sending an urgent referral to General Internal Medicine, Hematology or Vascular surgery. 30.5% of the patients with DVT were referred to General Internal Medicine (GIM) outpatient, compared to 24.5% to Hematology and 33.7% to their family doctor. 29.8% of the patients with SVT were referred to GIM, 7.9% to Hematology and 66.7% to their family doctor. 39.7% of the people with DVT were tested for thrombophilia, of which 10% tested positive for any type of thrombophilia. 29.8% were tested for TOO, of which 48.9% were found to have TOO and 11.1% received surgery for same.

Conclusion: Our study demonstrates that there is significant variability in the management of upper extremity clots, highlighting the lack of literature in this field. Developing a structured, standardized approach along with ongoing provider education could help reduce this variability and optimize management of this patient population.