Dialysis catheter

A dialysis catheter is a catheter used for exchanging blood to and from a hemodialysis machine and a patient. A dialysis catheter is a catheter used for exchanging blood to and from a hemodialysis machine and a patient. The dialysis catheter contains two lumens: venous and arterial. Although both lumens are in the vein, the 'arterial' lumen, like natural arteries, carries blood away from the heart, while the 'venous' lumen returns blood towards the heart. The arterial lumen (typically red) withdraws blood from the patient and carries it to the dialysis machine, while the venous lumen (typically blue) returns blood to the patient (from the dialysis machine). Flow rates of dialysis catheters range between 200 and 500 ml/min. If a patient requires long-term dialysis therapy, a chronic dialysis catheter will be inserted. Chronic catheters contain a dacron cuff that is tunneled beneath the skin approximately 3–8 cm. The tunnel is thought to add a barrier to infection. The most popular dialysis catheter sold on the market today is the split-tip dialysis catheter. This catheter comprises two free floating tips. The catheter is placed in one of the large veins. A common site is superior vena cava or SVC. An SVC catheter is placed by puncturing the internal jugular vein in the neck (most often on the right side), and the catheter is then advanced downwards toward the chest. Alternatively, an SVC catheter can be inserted via the subclavian veins. The femoral route is an inferior option, however, because the groin site is more prone to infection and also because the patient cannot sit upright.