Life-threatening pulmonary embolism is a frequent complication of many medical illnesses and surgical procedures when antecedent venous thrombosis is associated with low-flow states, venous injuries, obesity, prolonged immobilization, hypercoagulability, and the poorly understood effects of certain malignancies.
Anticoagulation is generally accepted as the primary therapy for thromboembolic disease. Venous interruption, proximal to the site of venous thrombosis, is usually reserved for patients who have recurrent pulmonary emboli despite well-controlled, adequate anticoagulation; those who have a large, life-threatening embolus such that an additional one might be fatal; those who cannot be anticoagulated because of potential bleeding problems or other contraindication for anticoagulation; or those who are developing progressive pulmonary hypertension from repeated emboli.
Superficial femoral ligation has been largely abandoned because of the inability to precisely localize the proximal extent of the process and the likelihood of undetected thrombus in the opposite extremity or deep pelvic veins. Inferior vena caval interruption avoids these uncertainties. Caval filters placed via the femoral or jugular veins are commonly used today for prophylaxis against pulmonary emboli and their use has replaced the application of partially occlusive serrated clips. Temporary and permanent filters are now commercially available, with the advantage of being able to remove the temporary filter when its presence is no longer clinically needed.
Since intravenous contrast is usually used during the procedure, absence of contrast allergy is imperative and if present, may require premedication. Kidney function should be assessed as well as the patient’s ability to lie flat for a period of time during and after the procedure. These patients may have impaired cardiac function and abnormal ventilation/perfusion of the lung, requiring vigorous cardiac and pulmonary support, and perhaps monitoring by an anesthesiologist.
Local anesthesia is favored. A secure intravenous catheter for medications (especially sedation) is essential. An anesthesiologist to manage the patient may be imperative if there is impaired cardiopulmonary function.
The patient is supine with the groin or right jugular area exposed and clipped of any hair. Fluoroscopy should be available. This procedure may be done preferably in a dedicated angiography suite.
The groin or neck access area is prepped and draped in the usual fashion and local anesthesia is administered. The jugular or femoral (figure 1) vein is accessed with an entry needle under ultrasound guidance if needed below the level of the inguinal ligament (figure 2). Using fluoroscopy a fine (0.018) access wire is guided up into the inferior vena cava in preparation for passage of a pigtail catheter into the inferior vena cava (figure 3). A venacavagram is obtained (figure 4). The position of the renal veins relative to a given vertebral body level is noted. ...