The most common complication of permanent vascular access in haemodialysis patients is thrombosis which accounts for 80% to 85% of AV fistula loss. Apart from venous stenosis (responsible for 80-85% of thromboses), other causes of fistula thrombosis include arterial stenoses (1 to 2%) and non anatomic problems such as excessive post-dialysis fistula compression, hypotension, high hematocrit, hypovolemia or hypercoagulable states (1-3).

A third attempt at creating an A-V fistula was successful and the patient was dialyzed without problems for two months when the fistula, without any apparent cause, stopped functioning. A complete laboratory evaluation for thrombophilia was requested.

The patient had a normal pro-thrombin time and partial thromboplastin time and fibrinogen was 350 mg/dL. There were no protein S ad C or anti-thrombin III deficiencies and the patient was negative for anti-phospholipids antibody. The hematocrit was 35%, cholesterol 220 mg/dL, triglycerides 180 mg/dL, plasma homocysteine 40 m Mol/L (normal values less than 12 m mol/L), C reactive protein 10 mg/L, liver enzymes were in the normal range. A new AV fistula in the left arm was created successfully (Figure 1).

Figure 1

 

Question 2