Revised Blood Chemistry Values

Revised Blood Chemistry Values

REVISED BLOOD CHEMISTRY
VALUES

by Priscilla
A. Laliberty, RD, LDN

FROM THE EDITOR: On April 20, 1998,
I received the following response to the article "Blood Chemistry Values
for Dialysis Patients", which was published in the April Edition (Vol.
13, No. 2) of VOICE OF THE DIABETIC. Ms. Laliberty informed us that some of
those guidelines have been revised. Here she sets the record straight. Be sure
to talk to your doctor and your dialysis team about your specific blood chemistry
values.
I would like to have you consider some
updated thoughts on specific dialysis blood chemistry values.
For Calcium, the "Accepted Normal
for Dialysis Patients" is now a little different from "normal values,"
because it has been shown that, when your calcium is a little higher than for
normal people, the action of the parathyroid gland is suppressed, thus the demineralization
of your bones common in long-term dialysis patients is decreased. The goal range
for this group is now 10- 11mg/dL. To get your calcium level higher, talk to
your doctor or dietitian. Calcium Acetate is best taken with meals to lower
phosphorous, but calcium carbonate is better, if taken between meals (without
food), to raise the calcium level. (Abbott Lab has wonderful teaching tools
to explain this. Another option your doctor has is IV or oral Vitamin D, already
processed into the form your body can use. (As your kidneys aren't working,
you'd need this form.)
Hematocrit (HCT) is the percentage of
red blood cells in your blood. Due to your kidneys not working, your body cannot
make red blood cells as it should. Amgen has a product called EPOGEN that is
used (by IV) during dialysis treatments. This erythropoietin works to make red
blood cells, but it needs available iron in order to work. If your HCT is less
than 30%, ask your dialysis team to look at your case. Average HCT is now about
32% nationally, with average range about 30-36%.
BUN--For dialysis patients, your Blood
Urea Nitrogen should be below 80mg/dL. I would say our patients (at Rhode Island
Renal Institute) are in the range of 60-70mg/dL. And the Blood Albumin should
be close to 4.0g/dL. In my 19 years of working with dialysis patients, I rarely
find them eating enough protein. (Editor's Note: Protein requirements for dialysis
patients may be different from those of End Stage Renal Disease [ESRD] patients
not undergoing dialysis!) My patients average 3.9g/dL for Albumin and have BUN
in the 60-70mg/dL range. If you have urine output, your BUN may be lower. If
your urine output changes, your BUN may go up, and then you may need to compensate,
with increased dialysis (ie. blood flow, dialysate flow, kidney size or clearance
ability, or time on dialysis.) If your number is high, another area to check
is your access. Are you using a catheter for dialysis, or do you have a problem
with recirculation? Your team at your unit can look at this.
"Know your Numbers" refers
to KT/V and/or URR. These numbers are available at your unit, and in one number
estimate how well you are dialysed, the adequacy of your dialysis.
Creatinine is considered to be one marker
of toxins in the blood. For dialysis patients, it will generally be in the 8
to 15mg/dL range. Most of our patients will be in the 8 to 12mg/dL range, but
some will be lower. For people with diabetes, the creatinine range may be 5
to 8mg/dL. If your urine output level drops (volume), you will see a rise in
your creatinine. You may need to increase your dialysis to compensate for this
change.