European journal of vascular surgery最新文献

Mannitol has previously been shown to reduce skeletal muscle reperfusion injury and postischaemic compartment pressure. The present study was designed to evaluate whether these effects result from hyperosmolarity or free radical scavenging. A rabbit hindlimb perfusion model was used to compare the effects of mannitol (n = 6), glucose (n = 6)-an isomer of mannitol without scavenging effect—and fasciotomy (n = 6) on oedema, compartment pressure, energy charge, and muscle injury after 4 hours of ischaemia and 2 hours of reperfusion. One limb from each animal received treatment, while the other limb served as an untreated control. Mannitol and glucose reduced (p < 0.05) muscle water content and decreased (p < 0.01) the compartment pressure. Fasciotomy had no effect on muscle water content but normalised compartment pressure. The increase in energy charge following reperfusion was improved (p < 0.05) and uptake of [Tc⁹⁹]methylenediphosphonate—an indicator of muscle injury—was reduced (p < 0.05) by mannitol only. In conclusion, mannitol reduces postischaemic oedema mainly by its hyperosmolar property whereas restitution of energy production and reduction of muscle necrosis seem to be an effect of free radical scavenging. The compartment pressure is reduced by hyperosmolarity and free radical scavenging.

Pseudoaneurysm of the femoral artery is a well known complication after diagnostic and therapeutic catheterisation. We report a case of voluminous postcatheterisation false aneurysm, which developed on a pre-existing deep femoral artery aneurysm. Infection by Staphylococcus aureus was demonstrated. After surgical exploration, rupture and external haemorrhage occurred before reconstructive surgery was possible. Due to the septic conditions only a lateral aneurysmorraphy was performed. Postoperative angiogram showed an acceptable result. An aneurysm of the deep femoral artery was also demonstrated on the contralateral side. This was scheduled for elective surgery. In conclusion, this complication could have been avoided by accurate puncture technique. Surgical exploration under local anaesthesia is ill-advised. Especially in patients with advanced vascular disease, non-invasive studies of the puncture site is recommended.

Pulse-spray thrombolysis (PST) is a new technique of accelerated peripheral arterial thrombolysis. This technique has been evaluated on 24 patients with limb ischaemia. Severe acute limb-threatening ischaemia with sensory and motor deficit was present in 11/24 (45.8%) patients. The median dose of recombinant tissue plasminogen activator (rt-PA) used was 18mg (10–35mg) injectd in a concentration of 0.33 mg/ml and bolus size of 0.2 ml. The median length of occlusions treated was 23cm (range 4–55cm). Complete initial lysis was achieved in 23/24 (95.8%) and limb salvage at 30 days was achieved in 18/24 (75%) of the cases. The overall 30-days mortality was 4/24 (16.6%) and 2/4 (50%) in those who required surgical intervention. The median duration of thrombolytic treatment was 137.5 minutes (range 35–1125 minutes) which is an 11-fold and significant reduction (p < 0.001, Mann-Whitney) in lysis time compared with the results of conventional low dose infusion of rt-PA at a rate of 0.5 mg/h in 120 consecutive patients in our unit. PST rapidly restores vascular patency and may become the treatment of choice for acute limb ischaemia including those at immediate risk of irreversible ischaemic injury which would not be considered suitable for conventional thrombolysis.

Changes in tissue oxygenation in the calf muscle were measured by near-infrared spectroscopy (NIRS) in 62 patients who complained of intermittent claudication in the calf during a treadmill test. Three distinctive patterns of oxygenated and deoxygenated haemoglobin were observed. None of the type 0 cases were severe (i.e., unable to walk for more than 5 minutes), while 37 and 82% of the type 1 and type 2 cases were severe, respectively. The mean maximum walking distance of type 1 was significantly longer than that of type 2 (179 ± 70 m and 109 ± 46 m, respectively; p < 0.005), while the mean ankle-brachial pressure index at rest of type 1 was not significantly different from that of type 2 (0.68 ± 0.19 and 0.61 ± 0.23, respectively). Our results indicate that NIRS can be used to accurately assess the severity of intermittent claudication.

Earlier studies have proposed that the time to reach peak hyperaemic flux recorded with laser Doppler (t_p) is a simple and accurate method of evaluating ischaemic limbs and possibly a method of estimating the peripheral vascular resistance (PR). The aim of this study was to investigate the relationship between the t_p and changes in limb vascular resistance caused by arterial stenosis. Forty postocclusive hyperaemia tests with arterial stenoses of different pressure gradients were performed in four pigs. A laser Doppler fluxmeter was used to record postocclusive hyperaemia in the skin of one hind limb. A specially designed tourniquet was used for the arterial occlusion. Proximal and distal to the occlusion level a snare was used to form different grades of stenosis. The PR (mmHgml⁻¹·-min⁻¹) was either estimated by infusion of a known blood volume into the tested limb over a given time period with simultaneous measurement of pressure or calculated on the basis of measurements of limb blood flow and blood pressure gradients. The t_p was closely related to total limb vascular resistance assessed by the blood infusion method (r = 0.83, p < 0.0003) and to the resistance calculated from volume blood flow and intraarterial pressures (r = 0.86, p < 0.0001). This study suggests that the t_p accurately reflects limb vascular resistance in an experimental model. Thus t_p may be used as a quantitative indicator of overall blood flow impairment, and should be evaluated in patients with lower-limb atherosclerosis.

Intraarterial bolus treatment with the prostacyclin analogue iloprost appears to have a prolonged beneficial effect on femorodistal bypass graft flow which extends beyond the duration of its vasodilator properties. The effect of iloprost on the microcirculation rendered ischaemic over the time course of a distal bypass operation was investigated in this study without the use of fluorescent light. Methods: A rat model was designed to allow prolonged direct observation of leukocyte-venular endothelial adhesion in a femorodistal bypass simulation. The extensor digitorum longus (EDL) muscle of 10 rats was subjected to two 30 minute periods of ischaemia by a non-venous occluding tourniquet and to simulate some of the changes of chronic ischaemia the adverse effect of ischaemia was accentuated by indirect electrical stimulation via the lateral popliteal nerve. Results: Intraarterial bolus treatment with iloprost significantly reduced the total numbers of leukocytes observed in EDL venules, and the numbers exhibiting evidence of adhesion by rolling or sticking to venule endothelium compared with saline controls at one hour post ischaemia. Ischaemia induced vasodilatation and reduced shear stress by a similar and significant amount in both groups. Conclusion: Two periods of ischaemia and reperfusion similar to those which occur during bypass grafting resulted in changes in the distal microcirculation consistent with reperfusion injury. Intraarterial bolus treatment with iloprost prevented these leucocyteendothelial changes. It appears iloprost may have a role in reducing leukocyte-induced reperfusion injury in femorodistal bypass surgery.

During the 10-year period August 1981 to 1991, 92 consecutive patients underwent revascularisation to the peroneal artery (40 to the upper third, 30 to the mid and 22 to the distal third). The male/female ratio was 1.6: 1 and the mean age was 72 years. Thirteen patients had independent mobility preoperatively while 58 had limited mobility and the remaining 18 were bed/ housebound. Following surgery the patients were prospectively evaluated and mean follow-up was 25 months. The 1 and 3 year patency rates were 67 and 59% respectively and cumulative limb salvage rates were 75 and 71%. Forty-four patients returned to independent mobility while 36 had limited mobility and 11 remained housebound. Reconstruction to the peroneal artery is a valuable adjuvant for limb salvage providing satisfactory cumulative patency and facilitating improved mobility.