Pathophysiology and treatment of edema following femoropopliteal bypass surgery.

Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this edema is not well understood. The Cochrane Library and Medline were used to retrieve literature on edema following peripheral bypass surgery. Factors other than local wound healing alone are suggested in the literature to play a role, given the severity and duration of this edema. Hyperemia, microvascular permeability, reperfusion-associated inflammation and lymphatic disruptions are likely to facilitate the development of edema. Preventive methods could be lymphatic-sparing surgery, intraoperative antioxidative therapy and postoperative elevation. Successful treatment strategies to reduce postoperative edema are based on lymph massage and external compression. In conclusion, the pathophysiology of edema following peripheral surgery is not fully understood, although reperfusion-associated inflammation and lymphatic disruptions are likely to play a crucial role. When future less-invasive techniques prove to be successful, postoperative edema might be minimized. Until then, a careful lymphatic-sparing dissection should be executed when performing a peripheral bypass reconstruction. Postoperatively, the use of compression stockings and leg elevation are currently the golden standards.

Ruptured abdominal aortic aneurysm: endovascular or open approach in a Dutch general hospital.

AIM: We compared the outcomes of 56 patients with a ruptured abdominal aortic aneurysm (RAAA) who underwent either open repair or emergency endovascular aneurysm repair (eEVAR) in a general hospital. It seems feasible that the availability of eEVAR for treatment of RAAA could lead to a decrease in hospital mortality. METHODS: We analyzed all admitted patients with a RAAA, between January 2006 and April 2008, eEVAR is compared to open repair. We studied 30 days mortality, intensive care unit stay, hospital stay, total blood loss and complications. RESULTS: Fifteen eEVAR procedures (26.8%) were performed. Mortality in the eEVAR-group was 26%, in the open repair-group 46%. Mean intensive care unit stay was 3.9 days and 4.8 days in the eEVAR-group and open repair-group, respectively. Mean hospital stay was 13 days and 10.5 days. The average blood loss was 210cc and 2760cc. The amount of blood products for transfusion was significantly higher in the open repair. Overall complication rate was not significantly different in both treatment groups. CONCLUSION: Treatment in a Dutch general hospital of a RAAA with an eEVAR procedure has a lower mortality in comparison to the open repair. Therefore, whenever possible the eEVAR is the preferred treatment method.

Evaluation of A-V impulse technology as a treatment for oedema following polytetrafluoroethylene femoropopliteal surgery in a randomised controlled trial.

OBJECTIVE: To investigate the efficacy of A-V impulse technology (A-V) for oedema prevention and treatment following PTFE femoropopliteal surgery. DESIGN: Prospective randomized clinical trial. MATERIALS: 36 patients undergoing PTFE femoropopliteal bypass reconstructions, either being treated postoperatively with a compression stocking (CS) (Group-1, n = 19) or with A-V (Group-2, n = 17). METHODS: Patients in treatment group-1 used a CS postoperatively during 1 week day and night, patients in group-2 were treated with A-V postoperatively at night during one week. The lower leg circumference was measured preoperatively and at five postoperative time points. RESULTS: Limb circumference has increased postoperatively on day 1 (CS 1.5%/A-V 1.4%), on day 4 (5.7%/6.3%), on day 7 (6.6%/6.1%), on day 14 (7.9%/7.7%) and on day 90 (5.8%/5.2%). Differences between treatment groups were not significant. A re-operation gives a significant 3.9% increase in circumference as compared to a first operation (95% CI: 1.5-6.4%; p = 0.002). CONCLUSION: No significant differences were found in the extent of developed edema between the groups following PTFE femoropopliteal bypass surgery. A redo peripheral bypass operation results in significantly more postoperative oedema than a first-time performed bypass operation.

Surgical removal of an infected aortic endoprosthesis using a wire cutter.

The purpose of this study is to report a new method of removing an infected endoprosthesis from the abdominal aorta using a wire cutter. A 65-year-old man with a ruptured abdominal aortic aneurysm was admitted to our hospital. He was treated with an endovascular abdominal endoprosthesis and discharged one week later. Three months after placement, the patient returned with an infection of the aortic endoprosthesis. The endoprosthesis had been fixed with barbs and hooks above the renal arteries and was surgically explanted by using a wire cutter to cut the hooks. The bare suprarenal stent was left in place. The patient was discharged one month after stent removal, and was treated with oral antibiotics for another ten weeks. At one year follow-up the patient showed no clinical, biochemical, or radiological signs of infection. In conclusion, infected endoprostheses should be surgically removed according to the medical literature. We recognize that removing a Zenith endoprostheses requires a dangerous operation because the hooks of the bare stent are engaged into the supra-renal aorta. This case report documents a new technique to safely remove an infected endoprosthesis with the help of a wire cutter.

Endovascular aneurysm repair with Zenith graft. Complications caused by leg extensions.

AIM: A large amount of Zenith endovascular stent complications is due to problems with the leg extensions. This kind of complication has never been reported in literature. The aim of this study was to monitor the complications of endovascular abdominal aneurysm repair (EVAR) performed with the Zenith endovascular graft occurred in the Amphia Ziekenhuis in Breda to see how many recurrences were due to leg extension. METHODS: The study enrolled all patients (N.=66) treated with the Zenith endograft in the period between October 2000 and September 2006. Mortality, complications and the number of reinterventions were analysed. Average age of the patients was 73.4 years, average follow-up was 24.5 months and average aneurysm size was 61.5 mm. Radiologic follow-up was performed by computed tomography scans and X-rays. RESULTS: Postoperative mortality rate was 0%. The overall mortality rate during follow-up was 3%. Ten patients required a total number of 12 reinterventions (15%). The average time for reintervention was 10 months after the primary operation. Mortality, complication and reintervention rates were comparable with those reported in the literature, but 75% of these reinterventions were related to the leg extensions. CONCLUSION: Authors observed that nine out of 12 complications which required reintervention were due to problems with one of the leg extensions. This is the first study that specifies clearly the percentage of problems with leg extensions in EVAR (75%). When placing a Zenith endovascular graft extra attention should be paid to optimal placement of the leg extensions.

Vascular endothelial growth factor (VEGF)-C differentially affects tumor vascular function and leukocyte recruitment: role of VEGF-receptor 2 and host VEGF-A.

Unlike vascular endothelial growth factor (VEGF)-A, the effect of VEGF-C on tumor angiogenesis, vascular permeability, and leukocyte recruitment is not known. To this end, we quantified in vivo growth and vascular function in tumors derived from two VEGF-C-overexpressing (VC+) and mock-transfected cell lines (T241 fibrosarcoma and VEGF-A-/- embryonic stem cells) grown in murine dorsal skinfold chambers. VC+ tumors grew more rapidly than mock-transfected tumors and exhibited parallel increases in tumor angiogenesis. Furthermore, VEGF-C overexpression elevated vascular permeability in T241 tumors, but not in VEGF-A-/- tumors. Surprisingly, unlike VEGF-A, VEGF-C did not increase leukocyte rolling or adhesion in tumor vessels. Administration of VEGF receptor (VEGFR)-2 neutralizing antibody DC101 reduced vascular density and permeability of both VC+ and mock-transduced T241 tumors. These data suggest that VEGFR-2 signaling is critical for tumor angiogenesis and vascular permeability and that VEGFR-3 signaling does not compensate for VEGFR-2 blockade. An alternate VEGFR, VEGFR-1 or neuropilin-1, may modulate adhesion of leukocytes to tumor vessels.

Tumor oxygenation in hormone-dependent tumors during vascular endothelial growth factor receptor-2 blockade, hormone ablation, and chemotherapy.

Tumor oxygenation is critical for tumor survival as well as for response to therapy, e.g., radiation therapy. Hormone ablation therapy in certain hormone-dependent tumors and antiangiogenic therapy lead to vessel regression and have also shown beneficial effects when combined with radiation therapy. These findings are counterintuitive because vessel regression should reduce oxygen tension (pO2) in tumors, decreasing the effectiveness of radiotherapy. Here we report on the dynamics of pO2 and oxygen consumption in a hormone-dependent tumor following hormone ablation and during treatment with an anti-VEGFR-2 monoclonal antibody (mAb) or a combination of doxorubicin and cyclophosphamide; the latter combination is not known to cause vessel regression at doses used clinically. Androgen-dependent male mouse mammary carcinoma (Shionogi) was implanted into transparent dorsal skin-fold chambers in male severe combined immunodeficient mice. Thirteen days after the tumors were implanted, mice were treated with antiangiogenic therapy (anti-VEGFR-2 mAb, 1.4 mg/30 g body weight), hormone ablation by castration, or doxorubicin (6.5 mg/kg every 7 days) and cyclophosphamide (100 mg/kg every 7 days). A non-invasive in vivo method was used to measure pO2 profiles and to calculate oxygen consumption rates (Q(O2)) in tumors. Tumors treated with anti-VEGFR-2 mAb exhibited vessel regression and became hypoxic. Initial vessel regression was followed by a "second wave" of angiogenesis and increases in both pO2 and Q(O2). Hormone ablation led to tumor regression followed by an increase in pO2 coincident with regrowth. Chemotherapy led to tumor growth arrest characterized by constant Q(O2) and elevated pO2. The increased pO2 during anti-VEGFR-2 mAb and hormone ablation therapy may explain the observed beneficial effects of combining antiangiogenic or hormone therapies with radiation treatment. Thus, understanding the microenvironmental dynamics is critical for optimal scheduling of these treatment modalities.