Superficial thrombophlebitis guidelines
Superficial venous thrombosis or thrombophlebitis (STP) in the lower limb is a relatively common, painful, and in many cases self-limiting condition. It can be sterile (majority of cases, associated with varicose veins), infective/traumatic (associated with trauma or cannulation, antibiotics may have a place) or migratory (rare, consider paraneoplastic cause).
Around 10-21% of patients with STP will already have DVT at presentation and a further 3-4% will progress to it if untreated. Patients with at least 5 cm of thrombus in a superficial vein are more likely to have underlying DVT if the STP is in the proximal long saphenous vein (within 10 cm of the saphenofemoral junction). Sterile STP within a varicose vein is less likely to be associated with underlying DVT. D-dimer is of no value, it may be elevated in both.
Patients with clinical signs of superficial thrombophlebitis affecting the proximal (above knee) long saphenous vein should have an ultrasound scan to exclude concurrent DVT.
Patients with STP within 3cm of the sapheno-femoral junction should be considered for therapeutic anticoagulation
Patients with superficial thrombophlebitis, without DVT, should have anti-embolism stockings and, if extending above the knee, be considered for treatment with prophylactic doses of LMWH for up to 30 days or fondaparinux for 45 days (JAMA 2018;320:2367). The absolute benefit of this strategy is small, with a NNT of 90. DOACs are not licensed for this indication but have been used.
If LMWH is contraindicated, or where the STP is confined to the calf, 8-12 days of oral NSAIDs should be offered. This reduces risk of extension and recurrence of STP but not DVT/PE risk.
There is insufficient evidence to support the use of topical heparinoids
Taken from the BCSH guidelines, page 7