Question

What is dialysis? Under what condition is it carried out? 

Answer 1

Dialysis involves the use of artificial kidney or a dialysis machine. The patient's blood is from the radial artery is led through the machine where excess salts and urea is removed. The purified blood is then returned to a vein in the same arm.
Dialysis is carried out in case of failure of both the kidneys. In case there is a permanent damage, then the dialysis is to be repeated for about 12 hours twice a week. 

Answer 2

An artificial kidney is a dialysis machine. When both the kidneys become fail to work the dialysis machine is used out. The patient’s blood is led from the radial artery in his arm through the machine where the urea and excess salts are removed and the purified blood is returned to a vein in the same arm. In case of permanent damage to the kidneys, dialysis has to be repeated for about 12 hours twice a week.