Nokea
The regulation of red blood cell (RBC) production is thought to be controlled by which physiologic factor?
- A. Hemoglobin
- B. Tissue hypoxia
- C. Reticulocyte count
- D. Number of RBCs
Correct Answer: B
Rationale: Tissue hypoxia triggers the kidneys to release erythropoietin, stimulating bone marrow to produce RBCs. Hemoglobin levels indirectly influence this through oxygen delivery, reticulocyte count monitors production, and RBC numbers don?t directly control production.
You may also like to solve these questions
A child with sickle cell anemia (SCA) develops severe chest and back pain, fever, a cough, and dyspnea. What should be the first action by the nurse?
- A. Administer 100% oxygen to relieve hypoxia.
- B. Notify the practitioner because chest syndrome is suspected.
- C. Infuse intravenous antibiotics as soon as cultures are obtained.
- D. Give ordered pain medication to relieve symptoms of pain episode.
Correct Answer: B
Rationale: Symptoms suggest acute chest syndrome, a medical emergency in SCA, requiring immediate practitioner notification. Oxygen may be needed but doesn?t reverse sickling, antibiotics follow evaluation, and pain management is secondary to addressing the emergency.
For children who do not have a matched sibling bone marrow donor, the therapeutic management of aplastic anemia includes what intervention?
- A. Antibiotics
- B. Antiretroviral drugs
- C. Iron supplementation
- D. Immunosuppressive therapy
Correct Answer: D
Rationale: Immunosuppressive therapy (e.g., antilymphocyte globulin, cyclosporine) treats aplastic anemia, likely an autoimmune condition, improving prognosis. Antibiotics treat infections, not the condition; antiretrovirals and iron are irrelevant to aplastic anemia management.
A mother states that she brought her child to the clinic because the 3-year-old girl was not keeping up with her siblings. During physical assessment, the nurse notes that the child has pale skin and conjunctiva and has muscle weakness. The hemoglobin on admission is 6.4 g/dl. After notifying the practitioner of the results, what nursing priority intervention should occur next?
- A. Reduce environmental stimulation to prevent seizures.
- B. Have the laboratory repeat the analysis with a new specimen.
- C. Minimize energy expenditure to decrease cardiac workload.
- D. Administer intravenous fluids to correct the dehydration.
Correct Answer: C
Rationale: A hemoglobin of 6.4 g/dl (normal 11.5-15.5 g/dl) indicates severe anemia, increasing cardiac workload to compensate for reduced oxygen delivery. Minimizing energy expenditure reduces cardiac strain. Seizures aren?t a risk, repeat testing is unnecessary, and dehydration isn?t evident.
What condition occurs when the normal adult hemoglobin is partly or completely replaced by abnormal hemoglobin?
- A. Aplastic anemia
- B. Sickle cell anemia
- C. Thalassemia major
- D. Iron deficiency anemia
Correct Answer: B
Rationale: Sickle cell anemia involves replacement of normal hemoglobin with abnormal sickled hemoglobin, a hemoglobinopathy. Aplastic anemia is bone marrow failure, thalassemia major involves reduced hemoglobin chain production, and iron deficiency affects RBC size, not hemoglobin type.
The clinical manifestations of sickle cell anemia (SCA) are primarily the result of which physiologic alteration?
- A. Decreased blood viscosity
- B. Deficiency in coagulation
- C. Increased red blood cell (RBC) destruction
- D. Greater affinity for oxygen
Correct Answer: C
Rationale: SCA causes increased RBC destruction due to sickled cells, leading to vasoocclusion and hemolysis. Sickled cells increase viscosity, not decrease it; coagulation is unaffected; and sickled hemoglobin has reduced oxygen affinity, transforming under low oxygen tension.