Nokea
What is the term for the ability of cardiac cells to respond to a stimulus by initiating a cardiac impulse?
- A. Excitability
- B. Contractility
- C. Rhythmicity
- D. Conductivity
Correct Answer: A
Rationale: The correct answer is A: Excitability. Excitability refers to the ability of cardiac cells to respond to a stimulus by initiating a cardiac impulse. This process is essential for the heart to function properly. Contractility (B) is the ability of cardiac muscle to shorten forcibly when stimulated. Rhythmicity (C) refers to the heart's ability to generate a regular rhythm of contractions. Conductivity (D) is the ability of cardiac cells to transmit electrical impulses. Excitability is the most fitting term in this context as it specifically describes the response of cardiac cells to a stimulus.
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How might the blood pressure be affected in a client whose body mass index (BMI) is 31 (obese)?
- A. increased
- B. decreased
- C. no change
- D. a change either way
Correct Answer: A
Rationale: Obesity is strongly associated with increased blood pressure due to factors like insulin resistance and increased vascular resistance.
Which surgical procedure involves opening or replacing a narrowed or blocked heart valve?
- A. Valve replacement
- B. Angioplasty
- C. Stent placement
- D. Coronary bypass surgery
Correct Answer: A
Rationale: The correct answer is A: Valve replacement. This surgical procedure involves opening or replacing a narrowed or blocked heart valve. During valve replacement, a damaged valve is removed and replaced with a new one to restore normal blood flow. Angioplasty (B) involves opening blocked arteries, stent placement (C) involves inserting a mesh tube to keep arteries open, and coronary bypass surgery (D) involves rerouting blood flow around blocked coronary arteries. These procedures are not specifically related to treating narrowed or blocked heart valves, making them incorrect choices for this question.
What is a condition where the lung's alveoli are permanently enlarged and damaged, leading to shortness of breath?
- A. Emphysema
- B. Bronchitis
- C. Atelectasis
- D. Pulmonary fibrosis
Correct Answer: A
Rationale: The correct answer is A: Emphysema. Emphysema is a condition where the lung's alveoli are permanently enlarged and damaged, causing shortness of breath. This occurs due to the destruction of the alveoli walls, leading to decreased surface area for oxygen exchange. This results in difficulty breathing and reduced oxygen supply to the body. Bronchitis (B) is inflammation of the bronchial tubes, not alveoli damage. Atelectasis (C) is the collapse of lung tissue, not enlargement. Pulmonary fibrosis (D) is scarring of lung tissue, not alveoli enlargement.
The nurse is administering digoxin to a client with a heart rate of 45 bpm. 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. Monitor the client's heart rate and reassess in 30 minutes.
Correct Answer: A
Rationale: The correct answer is A: Hold the digoxin and notify the healthcare provider. Digoxin is a medication that can slow down the heart rate, and a heart rate of 45 bpm is below the normal range. Holding the medication and informing the healthcare provider is the priority to prevent potential harm from further slowing the heart rate. Administering the digoxin as ordered (B) would worsen the bradycardia. Increasing the dose of digoxin (C) would be dangerous. Monitoring the client's heart rate and reassessing in 30 minutes (D) may delay necessary intervention.
Which type of medication helps to reduce the workload on the heart by slowing down the heart rate?
- A. Beta-blocker
- B. Calcium channel blocker
- C. Diuretic
- D. ACE inhibitor
Correct Answer: A
Rationale: The correct answer is A: Beta-blocker. Beta-blockers work by blocking the effects of adrenaline on the heart, which helps to reduce the heart rate. This reduction in heart rate helps to decrease the workload on the heart muscle, making it an effective treatment for conditions such as high blood pressure and heart failure.
Incorrect choices:
B: Calcium channel blocker - Calcium channel blockers work by dilating blood vessels and reducing the heart's workload by relaxing the muscles in the blood vessels, not by slowing down the heart rate.
C: Diuretic - Diuretics help the body get rid of excess salt and water, reducing blood volume and lowering blood pressure, but they do not directly affect heart rate.
D: ACE inhibitor - ACE inhibitors work by relaxing blood vessels to lower blood pressure and improve blood flow, but they do not specifically target heart rate reduction.