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Published in Anna Kowalewski, SBAs and EMQs in Surgery for Medical Students, 2021
A 25- year- old woman presents with an acutely painful left calf after flying home from Fiji. Ultrasound confirms deep vein thrombosis extending above the popliteal veins. She has recently missed a period and thinks she might be pregnant.
Cardiovascular system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
After venous cannulation, with the table semi-erect, contrast medium is injected under fluoroscopic control, during which PA and oblique lateral images are acquired of the calf veins filled with contrast. With a knee replacement in situ a lateral projection may be required to demonstrate the popliteal vein. As the injection continues, the contrast medium is observed as it flows proximally through the popliteal and femoral veins. Permanent PA images are acquired at different levels of the upper leg with the table horizontal. The tourniquet above the knee is then released to aid filling of the iliac veins, which may also be assisted by gentle calf pressure. Permanent images of the iliac vein usually completes the investigation.
Noninvasive Diagnostic Procedures in Clinical Thrombosis
Published in Hau C. Kwaan, Meyer M. Samama, Clinical Thrombosis, 2019
Ted R. Kohler, D. E. Strandness
The study is performed with the patient in the supine position with legs slightly elevated. An upper thigh cuff is inflated to 55 mmHg, occluding the venous outflow but not arterial inflow. After the volume tracing attains its maximum value the cuff is rapidly deflated. Venous capacitance of the calf (cc/100 cc tissue) is the maximum volume achieved with venous compression, and outflow (cc/100 cc tissue per minute) is the rate of fall of calf volume with release of proximal compression (Figure 2). With significant occluding thrombus at the level of the popliteal vein or above, venous outflow is reduced. This causes chronic venous engorgement and decreased venous capacitance.
Central Venous Catheter as a Novel Approach to Postoperative Thrombolysis in Patients with Acute Iliofemoral Deep Venous Thrombosis
Published in Clinical and Experimental Hypertension, 2023
Biyun Teng, Fenghe Li, Xuehu Wang, Hao Tian, Yu Zhao, Qiu Zeng
Several crucial premises are required for this CVC-directed POT: First, BTK venous access should be established to facilitate postoperative rehabilitation. Second, antegrade in-line flow from the popliteal vein to the IVC should be restored to maintain the effective thrombolytic concentration. Recent studies have shown that BTK venous access is feasible and safe for CDT placement for lower extremity DVT (30,37–39). Up to 20% of acute calf venous thrombosis may spread to the proximal deep vein, which significantly contributes to the development of subsequent PTS (40,41). BTK access provides sufficient space to clear the thrombus in the distal segments so that the incidence of PTS can be significantly reduced (39). Surprisingly, 74.36% of the thrombi in our cohort involved the popliteal vein, so the establishment of BTK access was justified. Moreover, thrombus clearance from the popliteal vein trunk can promote relief of calf swelling symptoms postoperatively, which may restore ideal inflow velocity and improve thrombolytic efficacy. Third, the puncture site of BTK is located in front of the calf, which is more suitable for supine operation and postoperative care. Finally, BTK access does not affect knee movement, thus providing sufficient convenience for early postoperative ambulation and rehabilitation training. Patients can even walk freely during thrombolysis without the restrictions of catheters and electronic pumps.
Fondaparinux cross-reactivity in heparin-induced thrombocytopenia successfully treated with high-dose intravenous immunoglobulin and rivaroxaban
Published in Platelets, 2020
Farheen Manji, Theodore E. Warkentin, Jo-Ann I. Sheppard, Adrienne Lee
A 70-year-old female (no previous heparin exposure) was admitted with confusion, headaches and behavioral changes; brain imaging revealed glioblastoma. She received unfractionated heparin (UFH) thromboprophylaxis prior to tumor resection, with heparin resumed post-craniotomy. Nine days after starting UFH (i.e., on postoperative day 4), the platelet count fell from 207 to 124, reaching 25 × 109/L (nadir) on day 12 after starting heparin (Figure 1). Later that day, venous ultrasound performed for left-lower limb swelling showed acute occlusive left popliteal vein thrombosis. Fondaparinux 7.5 mg subcutaneously daily was started for presumed HIT (pending laboratory results). Markedly reduced fibrinogen (0.7 g/L) and greatly elevated fibrin d-dimer level (7.28 mg/L) were shown.
Adventitial cystic disease of the popliteal artery
Published in Baylor University Medical Center Proceedings, 2019
Rachel Rendon, Kristyn Mannoia, William Shutze
In Patient 2, the popliteal vein was identified and separated from surrounding tissue. The popliteal artery was then identified and dissected from proximal to distal. It was evident that just distal to the knee flection, in the mid-popliteal space, there was circumferential cystic degeneration around the artery. This cystic structure was dissected off the adventitial surface of the popliteal artery for approximately 6 cm. The predominant area of stenosis was in the mid-popliteal space, and the cyst in this area was excised in its entirety. Duplex ultrasound confirmed no residual stenosis in the popliteal artery. The wound was then closed. At 1-year follow-up, the patient was symptom free and walking up to 30 minutes at a time. She had palpable bilateral posterior tibial pulses and minimal edema.