What is the ability of cardiac cells to respond to an impulse by transmitting the impulse along cell membranes?
- A. Contractility
- B. Automaticity
- C. Conductivity
- D. Rhythmicity
Correct Answer: C
Rationale: The correct answer is C: Conductivity. Cardiac cells have the ability to transmit impulses along cell membranes, allowing for the coordinated contraction of the heart. Conductivity refers to this specific property of cardiac cells to propagate electrical signals.
Contractility (A) refers to the ability of cardiac muscle cells to generate force during contraction. Automaticity (B) refers to the ability of cardiac cells to spontaneously generate electrical impulses. Rhythmicity (D) refers to the regularity of these electrical impulses in the heart. Conductivity is the most relevant choice as it directly addresses the transmission of impulses along cell membranes in cardiac cells.
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In Mrs. Jones' discharge teaching with a permanent pacemaker, which point should be covered?
- A. She should not get pregnant because her heart would not be able to tolerate the increased workload
- B. She should not exercise regularly
- C. She can return to the degree of sexual activity that is desired and tolerable for her
- D. It is not necessary to make a return visit to her physician
Correct Answer: C
Rationale: Sexual activity can generally continue with appropriate precautions.
The client on digoxin has a potassium level of 2.7 mEq/L. What is the nurse's priority action?
- A. Hold the digoxin and notify the healthcare provider.
- B. Administer the digoxin as ordered.
- C. Increase the dose of digoxin.
- D. Administer potassium supplements.
Correct Answer: A
Rationale: The correct answer is A: Hold the digoxin and notify the healthcare provider. A potassium level of 2.7 mEq/L is below the normal range (3.5-5.0 mEq/L), which can increase the risk of digoxin toxicity. Holding the digoxin and informing the healthcare provider is crucial to prevent potential harm. Administering the digoxin (choice B) can exacerbate toxicity symptoms. Increasing the dose of digoxin (choice C) is contraindicated due to the low potassium level. Administering potassium supplements (choice D) may be necessary, but the priority is to address the digoxin therapy first.
The client on furosemide is at risk for which electrolyte imbalance?
- A. Hypokalemia
- B. Hypernatremia
- C. Hyperkalemia
- D. Hyponatremia
Correct Answer: A
Rationale: The correct answer is A: Hypokalemia. Furosemide is a loop diuretic that increases potassium excretion in the urine, leading to low potassium levels (hypokalemia). This can cause muscle weakness, cramps, and cardiac arrhythmias. Hypernatremia (B) is high sodium levels, unrelated to furosemide. Hyperkalemia (C) is the opposite of what furosemide causes. Hyponatremia (D) is low sodium levels, not typically associated with furosemide use.
What procedure involves using a balloon to open a narrowed or blocked blood vessel, often followed by the placement of a stent?
- A. Angioplasty
- B. Valve replacement
- C. Coronary artery bypass graft (CABG)
- D. Endarterectomy
Correct Answer: A
Rationale: The correct answer is A: Angioplasty. Angioplasty involves using a balloon to open a narrowed or blocked blood vessel, followed by the placement of a stent to keep the vessel open. This procedure is commonly used to treat conditions like coronary artery disease. Valve replacement (B) involves replacing damaged heart valves, CABG (C) involves bypassing blocked coronary arteries using grafts, and endarterectomy (D) involves removing plaque from arteries, but none of these procedures specifically involve using a balloon and stent to open a narrowed or blocked blood vessel.
This test measures the amount of blood the heart pumps with each beat, often used to assess heart function.
- A. Ejection fraction
- B. Cardiac output
- C. Stroke volume
- D. End-diastolic volume
Correct Answer: A
Rationale: The correct answer is A: Ejection fraction. Ejection fraction is the percentage of blood pumped out of the heart's left ventricle with each contraction. It is a key indicator of heart function and can help diagnose heart conditions such as heart failure. Cardiac output (B) is the total amount of blood pumped by the heart per minute, not the amount pumped with each beat. Stroke volume (C) is the amount of blood pumped by the heart in one contraction, not specifically with each beat. End-diastolic volume (D) is the amount of blood in the ventricle before contraction, not the amount pumped with each beat.