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NU 506
Tracy Hill
Case Study 3 Anemia
Henry is 77 years old and lives with his daughter and son-in-law. He has chronic renal failure,
but likes to get out whenever he can to work in his daughter’s back yard garden. Over the last
few months he began to go outside less often. He said he was feeling unusually tired and he was
running out of breath doing the simplest of tasks. He also said his head ached and he often felt
dizzy. His daughter took him to his doctor, who performed a complete physical examination and
diagnosed Henry with anemia.
1. From what you know of Henry’s history, what type of anemia do you suspect he has? Explain
your answer, and include a brief description of how Henry’s red blood cells would appear on a
peripheral blood smear.
I would suspect Henry to have Chronic Disease Anemia, as it is the most profound hematologic
alteration that accompanies chronic kidney disease (Porth, p. 864). Chronic renal failure almost
always results in anemia, primarily because of a deficiency in erythropoietin. Persons with end
stage kidney disease often are anemic because of an inability of the kidneys to produce
erythropoietin. This is usually managed by the administration of recombinant erythropoietin
produced through DNA technology, to stimulate erythropoiesis.
2. Describe the physiological basis that would explain why Henry’s anemia would cause him to
have the symptoms he is experiencing.
When untreated, anemia causes or contributes to weakness, fatigue, depression, insomnia, and
decreased cognitive function. The kidneys are the primary site for the production of the hormone
erythropoietin, which controls red blood cell production (Porth, p. 864). Between 89-95% of
erythropoietin is formed in the kidneys. In renal failure, erythropoietin production usually is
insufficient to stimulate adequate red blood cell production by the bone marrow. On
cardiovascular function, the anemia of renal failure produces a decrease in blood viscosity which
exacerbates peripheral vasodilation and contributes to decreased vascular resistance. It also
causes a compensatory increase in heart rate, which causes a compensatory increase in cardiac
output to maintain tissue perfusion (Porth, p. 857). Anemia also limits myocardial oxygen
supply, esp. if someone has heart disease, which leads to angina and other ischemic events.
These physiologic events can cause symptoms of feeling tired and weak, short of breath, and
dizzy as well.
3. Predict the cellular adaptations erythrocytes undergo when chronic hypoxia is present. How
would this be evident on an oxygen-hemoglobin dissociation curve?
Anemia may contribute to the progression of chronic kidney disease by subjecting the
functioning nephrons that remain to increased hypoxic and oxidative stress. Severe anemia can
cause the oxygen dissociation curve to shift to the right, indicating that the tissue PO2 is greater
for any given level of hemoglobin saturation and represents reduced affinity of the hemoglobin
for oxygen at any given PO2 (Porth, p. 662). An anemic person may have a normal PO2 and
hemoglobin saturation level but decreased oxygen content because of the lower amount of
hemoglobin for binding oxygen (Porth, p. 663).
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