METHODS: This was a prospective study carried out in normal subjects at the Vascular Laboratory, Department of Surgery, Hospital Kuala Lumpur, from March 2006 to September 2006. The study compared the popliteal artery blood flow during change of posture from the horizontal (supine) to the sitting position and the effect of intermittent pneumatic compression (IPC) of the foot and calf on popliteal artery blood flow immediately and 10 minutes after cessation of compression.
RESULTS: A total of 15 subjects involving 30 limbs were examined in this study. On comparing flows between the horizontal and sitting position, there was a mean reduction in blood flow of 23% (p < 0.005). Immediately after compression of the foot and calf, there was an increase in blood flow of between 4% and 35% with a mean of 15% (p < 0.05). Peak systolic flows at 10 minutes postcompression were 536 +/- 95 mL/min, which was still significantly higher than precompression measurements.
CONCLUSION: There is a significant reduction in popliteal artery blood flow on changing from the supine to the sitting position. Popliteal artery blood flow is higher than baseline after 15 minutes of intermittent pneumatic foot and calf compression. The increase in popliteal artery blood flow is still present 10 minutes after cessation of IPC.
MATERIALS AND METHODS: We report 20 consecutive patients with end-stage renal failure (ESRF) who had central vein occlusion and were not amenable to endovascular intervention. They underwent extra-anatomical vein to vein surgical bypass. The axillary and iliac or femoral veins were approached via infraclavicular and extraperitoneal groin incisions respectively. In all the patients, an externally supported 6 or 8 mm polytetrafluoroethylene (PTFE) graft was used as a conduit and was tunnelled extra-anatomical. All patients had double antiplatelet (Aspirin and Clopidogrel) therapy post-operatively.
RESULTS: Substantial improvement in the facial, neck and upper limb swelling was noticed following this diversion surgery. The vein to vein bypass was patent at 12 months in 10 out of 20 patients. Graft infection occurred in two (10%) cases. Re-thrombectomy or assisted patency procedure (stent/plasty) was done in four (20%) cases. The patients with preoperative fistula flow rate of more than 1500 ml/min and post-operative graft flow rate of more than a 1000 ml/min were patent at 12 months (P=0.025 and p=0.034 respectively).
CONCLUSION: Axillary to iliac/femoral vein bypass can salvage functioning ipsilateral fistula threatened by occluded upper central vein.