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Which of the following characteristics are similar with respect to Factor VIII and von Willebrand factor (vWF)?
- A. Both are made in endothelial cells and megakaryocytes.
- B. Both are activated by thrombin.
- C. They are present in normal to high relative amounts in newborns.
- D. They are stored in Weibel-Palade bodies in endothelial cells.
Correct Answer: C
Rationale: Step-by-step rationale:
1. Factor VIII and vWF are present in normal to high relative amounts in newborns due to the physiological adaptation to the low levels at birth.
2. Both Factor VIII and vWF play crucial roles in the coagulation cascade, but their levels decrease after birth.
3. The other choices are incorrect because:
- A: Factor VIII is primarily made in endothelial cells and vWF is made in endothelial cells and platelets, not megakaryocytes.
- B: Thrombin activates Factor VIII but not vWF, which is activated by shear stress.
- D: Factor VIII is stored in Weibel-Palade bodies, but vWF is stored in platelets and endothelial cells, not in the Weibel-Palade bodies.
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A 12-year-old patient with localized osteosarcoma is being treated with cisplatin, doxorubicin, and high-dose methotrexate. The pain at his primary site rapidly resolves after initiation of chemotherapy. After tumor resection, pathology reveals the tumor was greater than 95% necrotic. You want to continue cisplatin, doxorubicin, and high-dose methotrexate. Which of the following is the best answer regarding the evaluations that should be performed to monitor for toxicity in patients receiving cisplatin, doxorubicin, and high-dose methotrexate?
- A. Complete blood count, creatinine, liver function tests
- B. Complete blood count, serum electrolytes (sodium, potassium, BUN, chloride), and EKG to monitor for prolonged QTc
- C. Complete blood count, creatinine, serum magnesium, audiogram, and echocardiogram
- D. Complete blood count, creatinine, serum magnesium, chest x-ray
Correct Answer: C
Rationale: The correct answer is C because it includes essential evaluations to monitor for toxicity associated with cisplatin, doxorubicin, and high-dose methotrexate.
1. Complete blood count: To monitor for potential bone marrow suppression caused by chemotherapy drugs.
2. Creatinine: To assess renal function, as cisplatin can cause nephrotoxicity.
3. Serum magnesium: Monitoring for hypomagnesemia, a common side effect of cisplatin.
4. Audiogram: To screen for hearing loss, a known side effect of cisplatin.
5. Echocardiogram: To evaluate for cardiotoxicity, especially with doxorubicin known to cause cardiomyopathy.
Other choices are incorrect:
A: Does not include serum magnesium, audiogram, and echocardiogram, which are important for monitoring toxicity.
B: While electrolytes and EKG are relevant, it lacks creatinine, serum magnesium, and other crucial tests.
D:
Which is not associated with hypersplenism:
- A. splenomegaly
- B. pancytopenia
- C. hyper cellular bone marrow
- D. reversibility by splenectomy
Correct Answer: C
Rationale: Rationale:
C: Hypercellular bone marrow is not associated with hypersplenism. Hypersplenism is characterized by splenomegaly, pancytopenia, and reversible by splenectomy. Hypercellular bone marrow is a feature of bone marrow hyperplasia, not hypersplenism.
A nurse is assessing a dark-skinned client for pallor. What action is best?
- A. Assess the conjunctiva of the eye.
- B. Have the client open the hand widely.
- C. Look at the roof of the client's mouth.
- D. Palpate for areas of mild swelling.
Correct Answer: A
Rationale: The correct answer is A: Assess the conjunctiva of the eye. This is because pallor, which is paleness of the skin, can be difficult to detect on dark skin. The conjunctiva of the eye is a mucous membrane that is not pigmented and can provide a more accurate indication of pallor. Options B, C, and D are not ideal for assessing pallor in a dark-skinned client as they may not show paleness accurately. B is more related to checking for pallor in fair-skinned individuals. C and D are not reliable indicators of pallor in any skin type.
Which is not associated with hypersplenism:
- A. splenomegaly
- B. pancytopenia
- C. hyper cellular bone marrow
- D. reversibility by splenectomy
Correct Answer: C
Rationale: Step-by-step rationale:
1. Hypersplenism is characterized by splenomegaly (A), causing sequestration and destruction of blood cells.
2. Pancytopenia (B) results from excessive destruction of blood cells in the enlarged spleen.
3. Hypercellular bone marrow (C) is not directly associated with hypersplenism; it is a compensatory response to increased blood cell destruction.
4. Splenectomy (D) can reverse the effects of hypersplenism by removing the source of blood cell destruction.
Therefore, the correct answer is C as hypercellular bone marrow is a secondary response to hypersplenism, not a direct association.
Outstanding feature of ITP:
- A. fever
- B. gum bleeding
- C. moderate splenomegaly
- D. stema tenderness
Correct Answer: B
Rationale: The correct answer is B: gum bleeding. In Immune Thrombocytopenic Purpura (ITP), the hallmark feature is thrombocytopenia leading to mucocutaneous bleeding, including gum bleeding. Fever (choice A) is not a typical feature of ITP. Splenomegaly (choice C) can be present in chronic ITP but is not a defining feature. Sterna tenderness (choice D) is not specific to ITP and is not considered a characteristic feature. Thus, gum bleeding is the outstanding feature of ITP due to the primary pathophysiology of decreased platelet count leading to bleeding manifestations.