Video Transcript
Hypoglycemia is a condition in
which the blood glucose level becomes lower than normal. Which of the following would most
likely cause this condition to a diabetic patient undergoing kidney dialysis if you
know that the patient is following a diabetes treatment? (A) If the dialysis fluid, or
purified liquid, contains very little or no glucose. (B) If the diabetic patient is on
an insulin-based treatment. (C) If the dialysis fluid, or
purified liquid, contains a high concentration of glucose. Or (D) if the dialysis fluid, or
purified liquid, contains a high concentration of insulin.
This question is asking us about a
patient who has two different conditions: diabetes and kidney failure. We’ll remove the answer choices
from the screen while we work out our solution. Diabetes is when the body has
trouble regulating the amount of glucose in the blood. Kidney failure is when the kidneys
stop properly filtering the blood and removing wastes. Diabetes is often treated with
insulin. Insulin is a hormone that helps to
regulate blood sugar concentration. Kidney failure is often treated
with dialysis. Dialysis is when a machine is used
to filter the blood.
During dialysis, the blood is
pumped out of the patient and through a network of semipermeable tubing. “Semipermeable” means that some
molecules can pass through and others cannot. Outside of the tubing, there is a
purified liquid called dialysis fluid. Dialysis fluid typically contains
water and ions, or salts. You may recall that molecules move
down their concentration gradient from areas of high concentration to areas of low
concentration. There is no waste in the dialysis
fluid, and there is some waste in the blood. So, the waste moves from the blood
and into the dialysis fluid. The dialysis fluid carries it
away.
This is how the process of dialysis
removes waste from the bloodstream for a patient with kidney failure. Let’s see how this process is
affected by the patient in our question also having diabetes. In a kidney failure patient who
does not have diabetes, the dialysis fluid is typically formulated without any
glucose. This means that any glucose in the
patient’s blood will likely be removed along with the waste. In these patients, this is not a
problem because their bodies regulate glucose in a normal way. They can recover quickly and
easily.
In a patient who has diabetes, the
dialysis fluid must contain some glucose. This prevents the glucose from
being removed from the blood during dialysis. In a diabetic patient, this is
important because their bodies do not regulate glucose in a normal way. It would be particularly dangerous
for a patient with diabetes to experience hypoglycemia, or low blood sugar.
Let’s bring back our answer
choices. We can eliminate two of our options
right away because neither is likely to cause hypoglycemia. The answer choice that says “If the
dialysis fluid, or purified liquid, contains a high concentration of insulin” might
cause hypoglycemia since insulin may cause the patient’s cells to increase their
intake of glucose from the blood. However, the question asks us for
the answer choice that is most likely. It is very unlikely that dialysis
fluid would contain insulin. Also, insulin would have trouble
diffusing through the semipermeable dialysis tubing.
The answer choice that is most
likely to cause hypoglycemia in a diabetic patient undergoing kidney dialysis is “If
the dialysis fluid, or purified liquid, contains very little or no glucose.”
