How does creatinine prevent chemotherapy?
Creatinine is a protein made by the muscles as they work. The muscle cells release it into the bloodstream. It circulates round to the kidneys, which remove it as the blood passes through. The amount of creatinine your kidneys produce in the urine is relatively constant for any one person and can be measured in a blood test. The blood test shows how fast the creatinine is being removed from the circulating blood. So it is a measure of your kidney function. If kidney function falls, the level of creatinine in the blood will rise and this will show up in your regular blood tests.

Some chemotherapy drugs can cause kidney damage. People having treatment with these drugs will have blood tests before each course of chemotherapy to make sure their kidneys are able to cope with the drugs. The blood test measures the level of creatinine in the blood to see how well your kidneys are working.

If you develop, or already have kidney damage, your doctor may alter the dose of the drugs you are having or may switch you to a different combination of chemotherapy drugs that is not so harmful to the kidneys. The kidneys may recover after a break from treatment. If you have very poor kidney function, you may not be able to have chemotherapy treatment as it may do too much harm.

To help prevent kidney damage it is important to drink plenty of water to help flush out your kidneys. With some drugs, you will be given fluids through a drip (intravenously) before and possibly after your treatment. At the same time, you may be given a drug to make you pass urine (a diuretic) – at least plenty of trips back and forth to the loo will help to pass the time!
http://www.cancerhelp.org.uk/help/default.asp?page=5067

Because cis-Platinum can cause kidney damage, intravenous fluids may be needed to "flush" the kidneys.
http://www.rtog.org/members/protocols/94-05/94-05.pdf

Cisplatin is a chemotherapy drug
http://www.cancerbackup.org.uk/Treatments/Chemotherapy/Indiv...