Nursing Elites

1. When educating a client about to undergo a pacemaker insertion, the nurse explains the normal phases of cardiac muscle tissue. During the repolarization phase, the nurse will stress that membranes must be repolarized before they can be re-excited. Within the cell, the nurse understands that:

• A. Potassium channels open while sodium channels close, causing repolarization to the resting state.
• B. The influx of calcium is the primary stimulus for the repolarization of cardiac tissue.
• C. Only the electrical activity within the heart will determine when repolarization occurs.
• D. The cell membranes need to stay calm, resulting in muscle tissue becoming refractory.

Correct answer: A

Rationale: During the repolarization phase of cardiac muscle tissue, potassium channels open while sodium channels close. This process is crucial for the cardiac muscle to return to its resting state after depolarization. Potassium moving out of the cell and sodium staying out helps reset the membrane potential and prepare the cell for the next depolarization phase. The influx of calcium is not the primary stimulus for repolarization in cardiac tissue; it is mainly involved in the depolarization phase. While electrical activity within the heart influences repolarization, the specific ion movements described in choice A are what physiologically drive repolarization. Cell membranes need to be in an active state during repolarization, not calm, to facilitate the necessary ion movements for muscle tissue to properly function.

2. Which of the following correctly identifies the plasma protein inflammatory mediator systems?

• A. Phagocytic, interferon, and complement systems.
• B. Complement, fibrinolytic, and clotting systems.
• C. Complement, clotting, and kinin systems.
• D. Complement, clotting, and acute phase reactant systems.

Correct answer: C

Rationale: The correct answer is C: Complement, clotting, and kinin systems. These are the three main plasma protein inflammatory mediator systems. The complement system helps in inflammation and immune responses, the clotting system is involved in blood coagulation, and the kinin system regulates inflammation and blood pressure. Choice A is incorrect because interferon is not part of the plasma protein inflammatory mediator systems. Choice B is incorrect because the fibrinolytic system is not a primary inflammatory mediator system. Choice D is incorrect because acute phase reactants are not part of the plasma protein inflammatory mediator systems.

3. Which of the following describes the etiology of a cerebrovascular accident (CVA)?

• A. A blow to the head from a hard object
• B. Lack of blood flow to part of the brain
• C. Excessive exercise, such as running
• D. A ruptured artery in the heart

Correct answer: B

Rationale: The correct answer is B. A cerebrovascular accident (CVA), or stroke, is often caused by a lack of blood flow to part of the brain. This leads to damage in the brain tissue due to the deprived oxygen and nutrients. Choices A, C, and D are incorrect. A blow to the head from a hard object can cause a traumatic brain injury but is not the etiology of a CVA. Excessive exercise like running does not typically lead to a stroke. A ruptured artery in the heart may result in a heart attack, not a cerebrovascular accident.

4. A patient has been diagnosed with cytomegalovirus (CMV). Which of the following drugs would be ineffective in the treatment of this disease?

• A. Ribavirin (Rebetol)
• B. Ganciclovir (Cytovene) IV
• C. Foscarnet (Foscavir) IV
• D. Valganciclovir hydrochloride (Valcyte)

Correct answer: A

Rationale: The correct answer is A, Ribavirin (Rebetol). Ribavirin is not effective against CMV. Choice B, Ganciclovir (Cytovene) IV, is a common treatment for CMV as it inhibits viral DNA synthesis. Choice C, Foscarnet (Foscavir) IV, is also used for CMV infections by blocking viral DNA polymerase. Choice D, Valganciclovir hydrochloride (Valcyte), is a prodrug of Ganciclovir and is effective against CMV. Therefore, Ribavirin is the drug that would be ineffective in treating CMV.

5. A patient presents with a chronic cough, night sweats, and weight loss. A chest X-ray reveals upper lobe cavitary lesions. Which of the following is the most likely diagnosis?

• A. Tuberculosis
• B. Pneumonia
• C. Lung cancer
• D. Sarcoidosis

Correct answer: A

Rationale: The correct answer is A: Tuberculosis. Cavitary lesions in the upper lobes are classic findings seen in tuberculosis. This infectious disease commonly presents with symptoms such as chronic cough, night sweats, and weight loss. Pneumonia (Choice B) typically does not present with cavitary lesions on chest X-ray. Lung cancer (Choice C) may present with similar symptoms but is less likely to cause cavitary lesions in the upper lobes. Sarcoidosis (Choice D) usually presents with bilateral hilar lymphadenopathy and non-caseating granulomas, different from the cavitary lesions described in the case.

Similar Questions