Superficial Thrombophlebitis and other clotting quagmires

Interview with hematologist Dr. Tom Deloughery about a smattering of clotting quagmires…Superficial Thrombophlebitis, Recurrent Pulmonary Embolism, Calf Vein DVT, Clotted PICC Lines, Starting (loading) dose of warfarin, low molecular weight heparin, widowmaker clots.

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Quandary 1. Recurrent pulmonary embolism

Your patient is on warfarin, INR is therapeutic and has another PE. What do you do?

Make sure it’s truly recurrent. If it is…

  1. How long have they been on anticoagulation? If it’s only a week, then the warfarin may not have had time to provide any benefit.
  2. If longer than a week and their INR has been therapeutic the whole time, consider that a warfarin failure. Start LMWH. This is a worrisome sign for an underlying malignancy or coagulopathy. LMWH is superior to warfarin for recurrent thromboembolic disease.
  3. On warfarin for years and has a recurrent PE. Do they get life long LMWH? Give LMWH for 3-6 months and, if they’re stable, restart the oral anticoagulant.

First dose of warfarin

1. How long to you need to wait to start warfarin after the first shot of LMWH? You can start both meds at the same time.

2. Is there a need for a loading dose of warfarin? Sort of….Dosing and effect are unpredictable. As a general rule, Tom gives young and otherwise healthy patients 10mg as a first dose. Over 65 or young and frail, first dose 5mg.

3. If your patient needs to restart warfarin after being off it for a while, do you need to bridge with LMWH until the INR is therapeutic?  In the setting of DVT and PE, yes. In atrial fibrillation, you probably don’t .

Superficial thrombophlebitis

Can  clot in the saphenous vein progress to DVT? Yes. 5-10%. Non saphenous vein clots progress to DVT at a rate of about 1%. As saphenous vein clot gets closer to the femoral vein, risk rises of it becoming a deep clot, but there are also perforator veins all along the saphenous vein that connect it to the deep system. Clot can connect from  the superficial (saphenous) vein to deep vein through a perforator at any point, but it’s less of a worry than deep propagation directly into the femoral vein near the groin.

Treating superficial thrombophlebitis needs to take into account the ‘thrombo’ (clot) and ‘itis’ (inflammation)

Tom’s approach

NSAIDS decrease rate of inflammation and clot extension

Therapeutic vs prophylactic LMWH: both decrease rate of inflammation and clot extension – outcomes are equal, so prophylactic LMWH is preferred (once a day, lower dose)

Small, under 5-7cm and not proximal (not upper half of thigh) NSAIDS

Larger than 5- 7cm or proximal, prophylactic dose of LMWH or fondaparinux (40mg daily)

Duration of therapy

There is uncertainty as to the optimal duration of therapy. Tom treats for two weeks. If patients are still symptomatic, treat for another two weeks.

Upper extremity thrombophlebitis

It is thought that upper extremity superficial thrombophlebitis has a more benign course. Treat with NSAIDS and hot packs. If this isn’t working, transition to LMWH.

What should you do with a PICC line clot?

Anticoagulation does not help with recannalization. Pull the line.

Putting in a new PICC right away – high rethrombosis rate.

Calf vein DVT

15-30% will grown and cause PE. Follow up ultrasound to check for extension is an option.

Unless there is a contraindication, treat with anticoagulation. ACCP recommends 3 months of treatment, Tom treats for 6 weeks.

Factor V Leiden mutation

9% prevalence in Portland, OR. Mostly a caucasion disease. Raises risk of first clot 3 fold (more DVTs than PE). Having this mutation does not increase risk of DVT recurrence.

Bonus point of the day

The SUPERFICIAL femoral vein is a DEEP vein. Perhaps the worst anatomic name ever. If you get a report that your patient has clot in the superficial femoral vein, that is a DVT, not superficial thrombophlebitis.









  1. Mark

    I consistently have difficulty with treatment of DVT’s with the population that I serve. Mostly because of financial problems the patients have with treatment. While warfarin is the cheapest per pill, it also includes several days, sometimes more than a week, of lovenox which is very expensive. The newer oral anticoagulants are not inexpensive either. The admitting medicine doctor often gives push back for trying to admit these patients, especially calf DVT’s, since the evidence shows that most DVT’s can be treated as an outpatient. From a pure EBM standpoint that is absolutely correct, however those studies do not factor in the financial problems many patients face. Any thoughts on this matter?

    1. Rob Orman

      Hi Mark. That’s a tough scenario. Overadmission for disorders (such as DVT) that can be treated as an outpatient is the reality in the situation you describe. It sometimes takes hospitalization to jump a small step that would be easy for a patient with financial resources. This is using the hospital as a safety net. Of course the patient can be treated with LMWH and warfarin as an outpatient, but there is a low probability of those meds getting filled in a patient with limited resources.

  2. Caroline Tababat-Khani

    Hi Rob!

    Hi Rob!
    I am an emergency physician in Sweden and I really enjoy listening to your podcasts while commuting to work. I was listenening to this episode last week and would really like to have a link to the article showing that LMWH in prophylactic dose is as good as LMWH in DVT-dose for treating superficial thrombophlebitis. When I have searched the literature myself I seem to only find evidence suggesting that DVT-dose is more effective (even though I realise that more research is needed for the topic). By tradition we treat these ST with LMWH in DVT dose 10-14 days, but if there is evidence for prophylactic dose I would love to change the recommendations here!
    Thanks again for making my drives full of wisdom and alot more fun!

    Caroline Tababat-Khani

    1. emergencypdx

      Hi Caroline. Sorry for the delay in reply. Here is the answer from Tom Deloughery…

      I based this on three trials. The STTESG trial looked at several doses of LMWH and prophylactic 8-12 was just as good as full dose (1). Then there was a trial of high vs low dose LMWH (2) that again show low dose just as good. They looked at this for a month of therapy. Finally the French looked at prophylactic dose fondaparinux and found benefit when given for 45 days. (3)

      So that is why I recommend prophylactic dosing. Based on the STTESG trial I start with 14 days of drug – if you look at the curves of the fondaparinux trial most of the benefit was seen in the first 10 days. So my approach is 40mg of enoxaparin for 14 days – if still symptomatic another 14 days of drug

      1. Arch Intern Med. 2003 Jul 28;163(14):1657-63. A pilot randomized double-blind comparison of a low-molecular-weight heparin, a nonsteroidal anti-inflammatory agent, and placebo in the treatment of superficial vein thrombosis. Superficial Thrombophlebitis Treated By Enoxaparin Study Group.
      2. J Thromb Haemost. 2005 Jun;3(6):1152-7. High vs. low doses of low-molecular-weight heparin for the treatment of superficial vein thrombosis of the legs: a double-blind, randomized trial. Prandoni P1, Tormene D, Pesavento R; Vesalio Investigators Group.
      3. N Engl J Med. 2010 Sep 23;363(13):1222-32. doi: 10.1056/NEJMoa0912072.Fondaparinux for the treatment of superficial-vein thrombosis in the legs.Decousus H1, Prandoni P, Mismetti P, Bauersachs RM, Boda Z, Brenner B, Laporte S, Matyas L, Middeldorp S, Sokurenko G, Leizorovicz A; CALISTO Study Group.

  3. Pingback: The LITFL Review 123 - LITFL

    1. Post
      Rob Orman

      This is controversial, but I’ll give you my take on the matter…
      Distal clots are not benign. They can cause PE, progress to proximal clots, and recur. Anticoagulating distal DVTs decreases the incidence of all of these. This risk of bad outcome is not as high as it is with proximal clot, but it is still a reality for the patient. I pursue any suspected calf clots and treat for 6 weeks if positive.

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