At the Bedside

Start with the event: venous vs arterial thrombosis, single vs recurrent, provoked vs unprovoked, and whether the clot occurred at an unusual site (portal, hepatic, cerebral venous sinus, splanchnic). Ask about recent surgery, immobility, pregnancy/postpartum state, malignancy, estrogen use, smoking, obesity, prior VTE, family history, and autoimmune disease.

Initial ED workup is driven by presentation:
  • Suspected VTE/PE: ECG, CXR, troponin/BNP if hemodynamic strain suspected, CTA chest or V/Q if indicated, leg US when helpful, CBC/CMP/PT/INR/aPTT.
  • Arterial thrombosis/stroke/limb ischemia: CTA/vascular imaging per syndrome, ECG for afib, CBC/CMP/coags.
  • Unusual thrombosis or recurrent thrombosis: consider antiphospholipid syndrome, myeloproliferative neoplasm (JAK2-associated), PNH, inherited thrombophilias, malignancy, and nephrotic syndrome.
Important exam clues:
  • APS: arterial + venous clots, livedo reticularis, miscarriages, thrombocytopenia.
  • MPN/polycythemia vera: plethoric appearance, splenomegaly, headache, thrombosis in unusual sites.
  • PNH: hemoglobinuria, abdominal pain, cytopenias, thrombosis in hepatic/portal/cerebral veins.
  • Nephrotic syndrome: edema, frothy urine, anasarca, hyperlipidemia.
Management in the ED:
  • Treat the clot first: anticoagulate if not contraindicated and syndrome warrants it.
  • If massive PE, limb-threatening ischemia, or bowel ischemia: activate reperfusion/thrombolysis/surgical pathways.
  • If APS is suspected and clot is confirmed, anticoagulation is typically warfarin-based long term after acute management; DOACs may be inferior in high-risk APS.
  • If cancer-associated thrombosis is likely, anticoagulation is still standard, but agent choice may differ based on bleeding risk and site.
  • Admit if hemodynamically unstable, significant clot burden, recurrent/unusual thrombosis, or diagnostic uncertainty requiring expedited workup.
A Classic Presentation
A 34-year-old woman with two prior first-trimester miscarriages presents with a swollen painful left leg and pleuritic chest pain after starting estrogen-containing contraception. She is mildly tachycardic, has unilateral leg edema, and CTA shows a segmental PE with DVT on ultrasound. Platelets are slightly low, and the history suggests antiphospholipid syndrome. She is started on anticoagulation, admitted, and referred for thrombophilia evaluation.
Patient Presentation to Attending
How you’d present this patient on the floor
“This is a 34-year-old woman with prior miscarriages and recent estrogen use presenting with unilateral leg swelling and pleuritic chest pain over the past day. My main concern is venous thromboembolism in the setting of a possible procoagulant state, especially because this is a relatively young patient with a clot history that feels out of proportion to her usual risk factors. She has left calf tenderness and edema, tachycardia, and no clear infectious symptoms or trauma. I’m less worried about pneumonia or isolated musculoskeletal pain because her symptoms are pleuritic with DVT findings, and there’s no focal lung exam abnormality or alternative explanation. CTA chest shows a segmental PE and ultrasound confirms proximal DVT; I’m also paying attention to the miscarriage history and mild thrombocytopenia, which raises concern for antiphospholipid syndrome. Overall I think she has acute VTE with a possible underlying thrombophilia, and I’m starting anticoagulation and admitting her for further evaluation and selection of long-term therapy.”

Study Directive

  • Draw a 1-page differential for unusual thrombosis: APS, MPN, PNH, malignancy, nephrotic syndrome, estrogen, pregnancy, HIT.
  • Make a table from memory of venous vs arterial clot patterns for each thrombophilia.
  • Review when thrombophilia testing is not useful in the ED vs when it may change disposition.
  • Practice an oral presentation for “young patient with first unprovoked PE.”
  • Rehearse the anticoagulant starting doses and which agents are avoided in severe APS.

Recent Literature