Kidney transplantation (also known as renal transplantation) is a surgical procedure to replace kidneys that are not working with a healthy kidney from a donor. The most common reason for someone undergoing a kidney transplant is chronic kidney disease. When the kidneys lose their function it is called kidney failure. People can survive with one kidney, therefore unlike other organ transplants, a living person can be a donor.
The surgeon transplants the new kidney in the abdomen and attaches it to the artery that supply's blood to the kidney and the vein that carries blood away. It is also attached to the ureter which carries urine from the kidney to the bladder. The surgery itself is not complex, however, the period after the surgery is critical due to the risk of rejection.