Dialysis and Renal Disease
In Episode 605, Invasion, 27-year-old Sarah Fremont has checked into Seattle Grace for a kidney transplant. Suffering from end stage renal disease for some time, Sarah has had to live the last three years scheduling her life around her dialysis sessions. Unfortunately for Sarah, her veins have not held up well and she has used up all but one of her access sites—Sarah says that they have literally run out of places on her body to stick the needles.
She is SO ready for this new kidney.
What are the causes of renal disease?
> Kidneys are in charge of keeping your blood clean. They take out all the extra waste, fluids, and minerals; they also manufacture hormones to keep up the strength of your bones and blood. However, if your kidneys malfunction and stop working, all of that waste? Sticks. It builds up, causing your blood pressure to rise while fluids accumulate in the body, not letting enough red blood cells be produced. This chain of events in turn affects other organs such as the brain, lungs, and heart.
Many illnesses, such as high blood pressure and diabetes, cause damage to the kidneys, disrupting the body's filtering process. Sometimes kidney failure can be linked to allergic reactions to various medicines, also called interstitial nephritis.
So, when do you need dialysis?
In order to decide when to start treatment, your doctor will run tests to see how far along the sickness has progressed. They will determine your GFR, or glomerular filtration rate—this number measures how much function the kidney still has. The doctor will run a simple blood test called a creatinine, and calculate the GFR. If it is below 30, the doctor will direct you to dialysis and/or kidney transplantation to be done now or in the near future. If the GFR is below 15, one of these treatments needs to begin immediately.
What does dialysis entail?
Two types of dialysis exist—hemodialysis and peritoneal dialysis. With hemodialysis, your blood travels through tubes into a machine (called a 'dialyzer' or 'artificial kidney') where it is cleaned of all its waste. After it has been cleansed, the blood returns through the tubes to your bloodstream. You connect your body to the machine through a series of tubes that lead from an 'access point'—an entrance to your bloodstream. Hemodialysis usually takes place at a center or hospital three times a week for three to five hours, depending on your condition. Recently they've invented ways that hemodialysis can be done at your home as long as you have a partner for help with the dialyzer.
Back to the access point, this entrance to the bloodstream may be done one out of three ways—through a fistula, graft, or catheter. A fistula is when surgeons connect an artery and nearby vein in your arm. A graft is when surgeons use tubing to connect an artery and vein in your arm or leg. When it is time for a session, two needles will be placed in the fistula or graft to connect to the tubes of the dialyzer.
Now, the third way to create an access point is through a catheter that is inserted directly into a vein through tubing, typically in the neck or upper chest. Since Sarah has used up all her access points, this is what she's using now. It is not an ideal situation because it is only a temporary fix.
Now, peritoneal dialysis does not use a machine—the cleaning is done completely inside the body. Using a catheter, you pass a cleansing solution (called dialysate) into the abdomen in which the lining (the peritoneum) naturally filters out the body's waste. After a few hours, you pass the solution out of the body and put in new solution. Dialysis patients can do this type of cleansing anywhere. The kidney specialists (nephrologists) can determine which method is best for particular patients (hemodialysis vs. peritoneal dialysis) on an individual basis.
How long can you be on dialysis before getting a kidney transplant?
People can live very full and productive lives on dialysis for years. As long as you take care of yourself and follow the treatment plan, you should feel well enough to continue on your daily routine.
Transplantation can occur at any time once the kidneys have failed. Just receiving one healthy kidney can replace the work of your TWO failed kidneys. And unless you experience infection or significantly high blood pressure, the surgeons will leave the two existing kidneys in your body—at one point, a person could have THREE kidneys inside of them, only one of which works. The non-working kidneys won't start working again.
For more information, please visit:
http://www.nlm.nih.gov/medlineplus/kidneyfailure.html
http://kidney.niddk.nih.gov/kudiseases/pubs/peritoneal/
