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Objective: To study the effect of polymorphonuclear leucocytes (PMNLs) on reperfusion injury in rabbit skeletal muscle and to evaluate the role of oxygen-derived free radicals in PMNL-mediated reperfusion injury., Experimental Design: An isolated rabbit limb perfusion model. Amputated hindlimbs were subjected to 4 hours of ischaemia followed by 2 hours of reperfusion with oxygenated Krebs' buffer., Setting: Department of experimental surgery., Animals: 14 rabbits., Interventions: In group I (n = 8), one limb from each animal was reperfused with PMNL-supplemented buffer while the other limb was reperfused with cell-free buffer (control). In group II (n = 6), SOD and catalase were added to the limb reperfused with PMNL-supplemented buffer while the other limb was reperfused with cell-free buffer without SOD and catalase (control)., Measures: PMNL accumulation as myeloperoxidase (MPO) activity, muscle necrosis as uptake of [Tc99]methylenediphosphonate (MDP), and oedema as increase in muscle water content (MWC). Electron microscopy was performed for histological demonstration of reperfusion injury., Results: Addition of PMNLs increased MPO activity (p < 0.05) and MDP uptake (p < 0.05) but did not affect MWC. SOD and catalase treatment of limbs perfused with PMNLs prevented the increase in MPO activity (p < 0.05) and reduced MDP uptake (p < 0.05) and MWC (p < 0.05). PMNLs aggravated histological changes seen after reperfusion., Conclusions: Reperfusion injury in skeletal muscle is, at least partially, mediated by PMNLs. Free radical scavengers reduce PMNL-dependent injury and prevent PMNL accumulation suggesting that oxygen-derived free radicals are mediators of PMNL-dependent injury and/or engaged in the interaction between PMNLs and the microvascular endothelium.

The role of the temporary AV-fistula in venous reconstructive surgery is described. The objectives are: increase of blood flow in the proximal thrombectomised vein or in the venous graft; prevention of immediate re- or graft thrombosis; provide time for endothelial healing; promote development of collaterals in case of occlusion. The management of acute ilio-femoral venous thrombosis with thrombectomy and temporary AV-fistula is presented with results of 120 operations. No mortality due to fatal pulmonary embolism. In the prospective randomised study comparing surgery with conservative treatment follow-up demonstrated 76% patent iliac veins in operated group compared to 35% in the conservative group. Ten patients with iliac vein obstruction had immediate reconstruction with PTFE graft and AV-fistula. Three grafts are still functioning after 7, 15 and 56 months respectively.

For comparative analysis of small vessel prostheses, 78 dogs underwent femoral artery replacement with autogenous vein, polytetrafluoroethylene (PTFE) or human umbilical vein (HUV) grafts. Thirty-six animals received antiplatelet therapy with piroxicam orally once a day. Three-hour deposition of 111In-labeled platelets was less on HUV than on PTFE grafts but still greater than on autogenous vein grafts. Accordingly, 3-hour patency rates were lowest with PTFE and highest with autogenous vein, although the difference between HUV and PTFE grafts was not statistically significant. One month following implantation, PTFE grafts had a higher patency rate than HUV grafts (p less than 0.05). Treatment with piroxicam decreased 3-hour platelet deposition, improved 1-month patency of both PTFE (p less than 0.05) and HUV (p less than 0.01) grafts, and decreased pseudointimal thickening on PTFE grafts (p less than 0.01). This experimental study did not demonstrate any clearcut difference in the performance of PTFE and HUV grafts. Piroxicam treatment improved the results with both grafts, which would justify future clinical trials with this simple antiplatelet regimen.

To identify common etiologies and allow a selective and effective management of acute iliofemoral venous thrombosis, 128 patients treated surgically (97 cases) or medically (31 patients) were analysed regarding possible underlying conditions. Chart review revealed that prolonged immobilization (25%), recent surgery (20%), and neoplasm (16%) were the most frequent etiologic factors. No underlying cause was detected in 34% of the patients, but more than one possible etiology were recorded in 29% of the patients. Chronic compression of the iliac vein was present in at least 13% of the operated cases. The multifactorial etiologic spectrum in iliofemoral thrombosis is basically the same as in calf vein thrombosis. Iliac vein compression, childbearing and perhaps estrogen intake seem to be more often associated with iliofemoral thrombosis. Initial survey regarding underlying causes permits tailored management for the individual patient. Surgical treatment is often successful but thrombi that develop secondary to chronic vein obstruction or neoplasm are preferably treated conservatively.

Radionuclide angiography (RNA), was compared to contrast phlebography (CP) for evaluation of iliofemoral venous patency. Twenty-three patients that six months earlier had been treated for iliofemoral venous thrombosis were investigated. The reproducibility of RNA was good as the interindividual and intraindividual variation was 80-85% and 90-95% respectively. The sensitivity of RNA was 91% in the iliac and 65% in the femoral segment. The specificity was 78% in the iliac and 74% in the femoral segment. The advantages as compared to CP are: easy performance, easy to repeat, no adverse reactions and visualization of the whole venous system. The disadvantages are: e.g. difficulties in interpretation in bilateral disease or abnormal anatomy. RNA is recommended as a screening method for suspected iliac venous obstruction and for follow-up of venous patency after iliofemoral venous thrombosis.