REBEL Core Cast 14.0 – Superficial Venous Thrombosis

Posted by Marco Torres on Jun 26, 2019

Superficial venous thrombosis refers to a clot and inflammation in the larger, or “axial” veins of the lower extremities and superficial thrombophlebitis refers to clot and inflammation in the tributary veins of the lower extremities. While we previously thought of this as a benign entity, we actually found the superficial venous thrombosis has been associated with concomitant DVT and PE.
Small, superficial clots can be treated with compression, NSAIDs, and elevation. These patients should be seen for follow up within 7-10 days to make sure the clot has not progressed.
Clots that are longer than 5 cm should be treated with prophylactic dosing of anticoagulation: fondaparinux 2.5mg subq once daily for 45 days or enoxaparin 40 mg subq once daily for 45 days.
Clots that are within 3 cm of the sapheno-femoral junction should be treated the same as a DVT.
A superficial thrombus could mean there is a deeper clot elsewhere, even in the other leg! Take a good history, perform a thorough physical exam and consider a bilateral lower extremity DVT study in concerning patients.

Definitions:

The term superficial phlebitis is used if the patient has pain and inflammation involving a vein but ultrasound shows no evidence of thrombus.
Superficial thrombophlebitis is generally used if the patient has pain, inflammation and thrombus in the tributary veins of the lower extremities.
Superficial venous thrombosis is used when the clot and inflammation are in the larger, or “axial” veins of the lower extremities and this is done really to help communicate that these are serious clots that have the potential to cause complications similar to deep vein thrombosis.

Cause for Concern:

Patients at risk of complications of their superficial venous thrombosis include: male gender, history of VTE, cancer, SVT in a non-varicose vein, large SVT >5 cm, or SVT involving the sapheno-femoral junction (SFJ).
Studies within the last 5 years showing that 25% of patients with a superficial thrombus also had a DVT and 5% of patients had a concomitant PE. (Frappe 2014, Cosmi 2015)
17% of the DVTs were found in the contralateral limb. (Cosmi 2015)

Evaluation:

Patients will present with pain and redness in the distribution of a superficial vein.
D-dimer has been shown to have high false negative rate for superficial venous thrombosis. (Cosmi 2015)
The diagnostic test of choice is ultrasound as this helps assess the length of the thrombus and evaluates for extension deeper veins.
Consider bilateral ultrasound as DVT may be found in concomitant extremity.

Treatment:

Small, superficial clots can be treated with compression, NSAIDs, and elevation. These patients should be seen for follow up within 7-10 days to make sure the clot has not progressed.
Clots that are longer than 5 cm should be treated with prophylactic dosing of anticoagulation: fondaparinux 2.5mg subq once daily for 45 days or enoxaparin 40 mg subq once daily for 45 days.
Clots that are within 3 cm of the sapheno-femoral junction should be treated the same as a DVT.

Core EM: Superficial Venous Thrombosis
EM Cases: Episode 88 – DOACs Part 1: Use and Misuse
LITFL: Venous Thromboembolism (VTE) Prophylaxis
Cosmi B. Management of superficial vein thrombosis. Journal of thrombosis and haemostasis : JTH. 13(7):1175-83. 2015. PMID: 25903684
Frappe P, et al the STEPH Study Group. Annual diagnosis rate of superficial-vein thrombosis of the lower limbs: the STEPH community-based study. J Thromb Haemost 2014; 12: 831–8. PMID: 24679145
Guyatt GH et al. Executive summary: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 141(2 Suppl):7S-47S. 2012. PMID: 22315257

Post Peer Reviewed By: Salim R. Rezaie, MD (Twitter: @srrezaie)