Vascular Access

A very important chapter of vascular surgery is the creation of vascular accesses for hemodialysis . These are patients with end-stage renal failure where their kidneys function poorly or not at all and cannot "clean" the blood of toxic substances.

In these cases, a vascular access is necessary that will ensure the "cleaning" of large volumes of blood in a relatively short period of time, will ensure the patient a good quality of life without complications, and will last as long as possible in the long term.

Usually the first vascular access that is preferred is called a fistula and is the creation of an internal arteriovenous communication in the forearm or arm area. The reason for this is to provide the patient with a vein with increased flow and reinforced walls, so that it does not clot after its puncture and connection to the dialysis machine. Important conditions for the creation of such an arteriovenous communication are very good and unobstructed blood flow in the artery with the absence of any stenosis, the sufficient diameter of the artery and vein that will be anastomosis as well as the unobstructed outflow of blood in the deep venous system up to the right atrium of the heart. In case the vein is not sufficient, there is also the solution of the synthetic graft (Shunt).

The fistula with an autologous vein is the best solution mainly due to its longer lifespan. The non-dominant hand is preferred with the best area being the forearm, just above the wrist, and the elbow as the second best. It can be used approximately one and a half months after the surgery, when the vein has “matured”, that is, has grown in diameter and wall thickness. In case of using the basilic vein, a second surgery is necessary with transposition of the vein from the deep to the superficial position for easier puncture ( superficialization ).

The synthetic graft, although it can be used more quickly (approximately 3 weeks after surgical placement), should generally be considered a secondary solution, mainly because its patency is less than that of a fistula. It also has a high cost and a higher risk of infection due to frequent punctures.

When the indication for immediate hemodialysis occurs before the placement or maturation of a fistula, or when a fistula is blocked and can no longer be repaired, the emergency solution is temporary or long-term central venous catheters . These can have a single or double lumen. Double-lumen catheters are usually used. All catheters have an increased risk of infection and are only a temporary solution until a fistula is placed. The main difference between long-term catheters and temporary ones is that the former are placed through a subcutaneous tunnel , which reduces the risk of infection and can be used for months, perhaps even years, with appropriate care from the nursing staff and the patients themselves.

In case of need for vascular access for chemotherapy or long-term intravenous administration of drugs, a catheter is placed using a similar technique through the cephalic or internal jugular vein to the right atrium of the heart, which is connected to an infusion chamber ( Port) , which in turn is placed subcutaneously in the chest area and allows the administration of drugs from there.