What is the clearance test in peritoneal dialysis?

The clearance test in peritoneal dialysis measures how effectively that process is working. During peritoneal dialysis, a cleansing solution is infused into the abdomen of a person whose kidneys don't work, where it pulls wastes and extra fluids from the blood. The solution contains dextrose (or another sugar), salt and minerals dissolved in water. A catheter (soft tube) fills the abdomen with the solution. The solution mixes with wastes, salt and liquid, and all are removed when the solution drains out. This filling and removal process is called an exchange.

The clearance test involves studying waste solution samples from 24 hours, along with a blood sample taken during the same day. Doctors compare the levels of urea (urinary waste material) in the solution and in the blood to see how well it's being removed. If peritoneal dialysis isn't working effectively enough, doctors may:
  • increase the number of daily exchanges
  • increase the amount of peritoneal dialysis solution used in each exchange 
  • use solutions with higher dextrose concentrations

Continue Learning about Dialysis


Healthy kidneys remove waste from your blood and produce hormones your body needs. If your kidneys fail, you either need a kidney transplant or dialysis. Dialysis is a procedure that uses a machine to perform many of the functions ...

of the kidney. Dialysis can help prevent problems resulting from kidney failure and it allows people with kidney failure to live productive lives. Dialysis filters your blood, and like a health kidney, removes waste from your blood. Patients using dialysis are also required to follow a strict diet in order to stay healthy. There are two types of dialysis: hemodialysis and peritoneal dialysis. There are different advantages and disadvantages with both hemodialysis and peritoneal dialysis. Talk to your doctor about which type of dialysis would work better for you.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.