What is that chronic renal failure?
Kidneys use filter to remove impurities that our body produces.
In some diseases, the filtering power of the kidneys gradually alter, one speaks of chronic renal failure.
The marker of this disease is the increased clearance. Normal is 100 ml/min, (we can draw a parallel with percentages). 30 ml/minute, only 30% of the kidney filter works.
We’re talking about kidney failure light for a clearance between 89 and 60 ml/minute, moderate between 60 and 30 ml/minute, severe between 29 and 15 ml/minute and senior year below 15 ml/minute. It’s from a clearance to 15 ml/minute to consider replacing the function of the kidney, either by an artificial kidney (haemodialysis), evening a kidney from someone else (registry).
What are the causes of chronic kidney failure?
It affects 2 million people in France and the terminal shape 50 000 people.
In these 50,000 people, around 20 000 will be grafted and 30 000 will be dialysées.
The most common causes of non insulin-dependent diabetes, high blood pressure, a disease of the kidney prior (Hyderabad), immune causes, genetic causes, urinary infections repeatedly.
Why create a first of hemodialysis?
Dialysis is an artificial kidney, which is a machine making a filtration of the blood on an extra-corporel circuit.
The machine takes the patient’s blood, the fact through filters to return it to the patient “clean.”
We can’t achieve this circuit directly into an artery or a vein hemodynamic and mechanical reasons. Indeed the dialysis machine requires a throughput of 400 ml/minute.
To achieve such throughput:
– either a catheter is positioned in the large veins near the heart: central venous catheter (‘perm-cath’, palindrome catheter, catheter Canaud, of Grosshung).
– either we realize a direct surgical communication between an artery and a vein: we’re talking about medical-venous fistula. This type first is one that shows the best results (permeability, complications.) In general, must achieve this fistula a few months before the beginning of dialysis to allow time for the vein to grow. Usually we realize this fistula on the arm not dominant, starting with the end of the limb. (wrist, then the elbow…)
What are the tests to be done before?
The clinical examination is essential. Taking pulse, review of superficial venous capital under tourniquet.
It will be supplemented by a record echo-doppler venous and arterial of the upper limbs.
So the ideal site will be chosen favouring the non-dominant member and the distalite.
Example: Fistula on the left wrist for a right-handed patient.
What are the different fistula?
-The radio-medians or radio-cephalic fistula distal (at the outer edge of the wrist).
-Radio-cephalic averages (at the outer edge of the front arm).
-Humero-cephalic fistula (in the bend of the elbow of the outer edge of the arm)
-Fistulas humero-basilicas (in the bend of the elbow to the inner edge): this type of fistula must generally secondarily have a second intervention to superficialiser the Basilic vein to make it more easily ‘piquable ‘.
-In the case of a bad quality vein branch artery to a deep vein by a prosthetic bypass.
What are the complications?
So arterialisee superficialisee lucky can present several complications:
- Stenoses: making difficult dialysis or causing bleeding extended about to puncture after dialysis. These strictures will be handled by a dilation Endovascular in the operating room under local anesthesia on an outpatient basis.
- Aneurysm: the flow in the vein can cause a very significant dilation of the vein, one speaks of aneurysm. They treat surgically.
- Connect directly to a vein on the artery of the wrist or elbow can cause a lack of blood supply to the hand. We talk about vascular flight. The symptoms are:
- the appearance of pulp necrosis of sores on the fingers that heal no pain on the finger during dialysis.
- These flights are treated either by closing the fistula, either by performing a shunt thereof by a bypass between the artery upstream and downstream artery to limit this flight of blood (DRILL). Are also described important about to puncture, the strictures on the donor artery who treat themselves also.