Consumer Interest
Medical Issuses > Adequacy
Treatment adequacy refers to the amount of dialysis you get and the measurement that determines if it is enough to remove waste products. The amount of dialysis needed for a 100-pound person is not the same as the amount needed for a 250-pound person. If enough waste products are not removed you will feel sick and you will not have the energy to do much.
Hemodialysis
Hemodialysis adequacy is determined by looking at the results of blood sample analysis done both before your dialysis treatment and once your treatment is finished. This analysis is done at least once each month. It may be done more often if there has been a change in your prescription or you have been ill. You can ask your nurse to explain this to you and show you your results for the past few months.
The blood test used is called blood urea nitrogen (BUN). Your BUN should be high at the start of treatment and much lower when your treatment is finished. The amount of blood urea nitrogen removed during treatment is calculated by looking at this value before the start of treatment and after the treatment is finished. That is the reason two samples are taken on the same day each month.
The result of the calculation done with the two blood test values is called the Urea Reduction Ratio or URR. The desired minimum URR is 70%. In other words, the BUN in dialyzed (processed) blood should be reduced by 70% during each treatment. URR greater than 70% has been associated with better patient outcomes. These patients feel good, have more energy to do the things that are important to them and live longer.
There are 3 basic variables involved in trying to achieve an adequate dialysis: the size of the dialyzer, the blood flow rate/dialysate flow rate and the length of treatment. These can be adjusted to reach a good BUN level.
You can see more information about hemodialysis adequacy at:
http://www.kidney.niddk.nih.gov
http://www.kidney.org
Peritoneal Dialysis
Peritoneal dialysis adequacy can be determined by taking peritoneal fluid samples and blood samples. The membrane's ability to transport is assessed by the fluid samples. The transport ability helps the doctor to prescribe therapy that is best for you with either continuous ambulatory peritoneal dialysis (CAPD) or continuous cycling peritoneal dialysis (CCPD).
Peritoneal membrane characteristics vary from one person to another. This testing proves to be a very reliable and useful tool for your dialysis staff. It determines how much dialysis is needed to keep you healthy and give you the energy to do the things that are important to you.
In peritoneal dialysis, creatinine is the substance that is looked at to determine if your treatment is adequate. The laboratory tests used for peritoneal dialysis adequacy are creatinine clearance and the calculation referred to as Kt/V which measures the movement of urea out of the body .
The minimum creatinine clearance value should be 60 liters/week for CAPD and higher for the automated methods. The minimum Kt/V should be 2.0 for CAPD and higher for the automated methods. The variables to achieve an adequate PD treatment are number of exchanges, duration of dwell time, the amount and type of fluid used and method. These can be changed to improve your results.
More peritoneal dialysis adequacy information can be seen at:
http://www.kidney.niddk.nih.gov
http://www.aakp.org