43 year old male with recent ORIF of right tibial fracture. He is 6 weeks post op and the post operative splint has been removed.
He was diagnosed 4 days ago with 5cm thrombus in anterior tibial vein on formal ultrasound in the vascular lab. Given the DVT was provoked, the splint was removed and he has no further DVT risk factors, surveillance was recommended.
He presents concerned about pain behind his right knee and increased swelling of the distal limb. It is 2230.
1. Describe the factors will guide your management of this patient in the ED at this hour.
• Formal ultrasound in the vascular lab is not available.
• Risk of DVT propagation necessitating anti-coagulation
• Risk of bleeding if considering anti-coagulation- HAS BLED
• Personal ultrasound competence and experience in diagnosing proximal DVT
2. Explain how you would use ultrasound to guide your management.
• Compressive ultrasound can be used to identify thrombus in the proximal deep veins.
• If propagation into the popliteal vein has occurred then anti-coagulation will be necessary prior to formal ultrasound in the morning.
3. What bedside ultrasound findings would necessitate anti-coagulation?
• Thrombus identified in proximal deep veins
– Common femoral vein
– Deep femoral vein/ femoral vein
– Popliteal vein
• Superficial veins do not require anti-cogulation
– Great and small saphenous veins
• Anti-coagulation of distal vein DVT is controversial and regular surveillance to ensure no proximal propogation has occurred may be considered in patients with no ongoing risk factors for DVT.
– Crural: anterior tibial, posterior tibial, peroneal veins
– Muscular: gastrocnemius, soleal veins
4. Describe your approach to ultrasound in this case.
- Position patient with head up to ensure venous filling. Externally rotate the leg
- Use linear probe unless patient is obese in which case may need curvilinear for penetration
- Commence ultrasound at inguinal ligament
- Identify common femoral vein proximal to entry of great saphenous vein
- Interrogate with PW and colour Doppler if non compressible
- Perform the three point compression test to demonstrate compressibility of the vein at the following locations:
a. Common femoral vein (at and above the junction with the great saphenous vein)
b. Femoral vein
c. Popliteal vein
6. Supplement three point compression test with scanning of femoral vein until it enters the adductor canal – ensure compressibility of vein (winking) every few cms.
The following is a transverse view of his popliteal fossa with and without compression.
5. Is there thrombus present in the popliteal vein?
• Full compression of popliteal vein indicates no thrombus present
6. How do you manage this patient?
• Able to be discharged without anti-coagulation. Could consider shared decision making with patient after outlining risks of anti-coagulating or not.
• May return in the morning for formal vascular lab ultrasound without anti-coagulation.