Week 13 & 14: The Ballet Dancer (PCL 11)

Angela Says:
SURGICAL MANAGEMENT:
DVT:
Surgical treatment tends to be used when medical management, i.e. fibrinolysis or anticoagulation is inadequate to dissolve the clot or when it is contraindicated due to recent surgery, trauma to the CNS etc.
Venous thrombectomy is used to extract the clot and maintain venous patency.
· Firstly the location and extent of the clot is worked out using ultrasound or venography
· The patient is placed on heparin (if not already done so)
· An incision is made to expose the femoral vein and a “Fogarty” catheter is inserted until it squeezes past the clot
· The balloon on the catheter is inflated and the catheter is pulled out slowly, dragging the clot with it
· There is a risk that the clot may become dislodged or break into smaller pieces during the procedure which could lead to PE
· Venous valves may sometimes prevent the passage of a catheter in a retrograde direction down the leg. In this case, the leg may be wrapped tightly with an Esmarch bandage in an attempt to force clot extrusion.
· Heparin is given for 6-12 months after surgery and leg compression devices may also be used.
· If thrombosis is associated with an underlying defect, it must be identified and corrected after the resolution of the DVT, or the thrombosis will recur.

Other procedures:
New percutaneous mechanical techniques have been developed, such as angioscopic thromboembolectomy (same procedure without making an incision in the vein, rather a scope is inserted), mechanical disruption thrombectomy (a laser or other device is used the shake up the clot without invasive surgery) and aspiration thromboembolectomy (aspirates the clot through a needle).

Some of the mechanical devices available today combine clot maceration with suction removal (eg, AngioJet, Hydrolyser, Oasis), while others (eg, the Amplatz device) use clot maceration alone. Maceration at the catheter tip can be achieved by use of physical cutting blades, by vortex, by high- or low-pressure saline jets, by suction alone, or by ultrasonic liquefaction.
After the thrombus has been removed, construction of a small arteriovenous fistula may assist in maintaining patency by increasing the flow velocity through a thrombogenic venous segment.

Source: emedicine: DVT

PULMONARY EMBOLISM (PE):
Treatment usually focuses on oxygen therapy and blood-thinners, drugs to raise blood pressure may also be given.
Again, a catheter technique can be used, the most common being suction thrombectomy. The catheter shoots a salt solution into the blocked vessel, which by increasing the blood osmolarity, pulls water out of the cells and into the vessel which helps break up the clot. Mechanical devices as mentioned above may also be used.

Rarely, physicians recommend open surgery for a pulmonary embolism as mortality can be as high as 25%. The procedure is called pulmonary embolectomy and can involve inserting a catheter via the femoral or internal jugular vein and using fluoroscopic guidance to navigate into the pulmonary artery. Emboli are then extracted from the pulmonary bed using a cup device and syringe suction. Alternatively open surgery may be required but this is extremely rare. Cardiopulmonary bypass (heart-lung machines) may be used to stabilise the patient before the surgery.
Indications for surgical intervention include:
-massive pulmonary embolism
-patient is very ill with no response to anticoagulation or thrombolysis, or thrombolysis is contraindicated because of:
--Recent surgery - within 5 days of operation (10 days of hip operation
--Active bleeding from the bowel or urinary tract etc.

A metal filter, inserted via a catheter, may be placed into the superior and/or inferior vena cava to prevent recurrence

Sources:
-VascularWeb: Pulmonary Embolism, available at: http://www.vascularweb.org/_CONTRIBUTION_PAGES/Patient_Information/NorthPoint/Pulmonary_Embolism.html
-GP notebook: Pulmonary embolectomy, available at:
http://www.gpnotebook.co.uk/cache/-1590362084.htm
-ABC7chicago.com: Pulmonary Embolism, available at:
http://ww2.abc7chicago.com/global/story.asp?s=1230257