What does the PR interval measure?
- A. Time it takes for the electrical impulse to travel from the atria to the ventricles
- B. Measurement of ventricular depolarization
- C. Duration of ventricular repolarization
- D. Segment representing the time between ventricular depolarization and repolarization
Correct Answer: A
Rationale: The PR interval measures the time it takes for the electrical signal to travel from the atria to the ventricles, reflecting atrial depolarization and the delay at the AV node before ventricular activation. Option A is correct as it accurately describes the PR interval. Option B is incorrect as the PR interval does not measure ventricular depolarization. Option C is incorrect as the PR interval does not represent ventricular repolarization. Option D is incorrect as it describes the QT interval, not the PR interval.
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What is a condition where the right side of the heart fails due to increased pressure in the pulmonary arteries, often caused by chronic lung disease?
- A. Cor pulmonale
- B. Heart failure
- C. Pulmonary embolism
- D. Myocarditis
Correct Answer: A
Rationale: The correct answer is A: Cor pulmonale. Cor pulmonale is right-sided heart failure due to increased pressure in the pulmonary arteries, typically caused by chronic lung disease. This leads to the right side of the heart working harder to pump blood through the lungs, resulting in eventual failure. Pulmonary embolism (C) is a sudden blockage in the pulmonary artery, not a chronic condition. Heart failure (B) is a general term for when the heart is unable to pump blood effectively, not specific to the right side. Myocarditis (D) is inflammation of the heart muscle, not directly related to pulmonary hypertension.
The client on spironolactone (Aldactone) has a potassium level of 5.8 mEq/L. What is the nurse's priority action?
- A. Hold the spironolactone and notify the healthcare provider.
- B. Administer a potassium supplement.
- C. Continue the spironolactone as ordered.
- D. Increase the dose of spironolactone.
Correct Answer: A
Rationale: The correct answer is A: Hold the spironolactone and notify the healthcare provider. The priority action is to stop the medication and inform the healthcare provider because a potassium level of 5.8 mEq/L is above the normal range (3.5-5.0 mEq/L), indicating hyperkalemia. Spironolactone is a potassium-sparing diuretic that can further increase potassium levels. Continuing the medication or administering a potassium supplement would exacerbate the issue. Increasing the dose of spironolactone would be unsafe and could lead to severe complications. Therefore, holding the medication and seeking guidance from the healthcare provider is crucial in managing the client's elevated potassium level.
If Mr. Lane, with essential hypertension, complains of dizziness when changing position, your evaluation would be that Mr. Lane
- A. is probably not taking his medications properly
- B. should be instructed in preventing hypotensive reactions
- C. is responding as expected to the prescribed medications
- D. should be totally reevaluated
Correct Answer: B
Rationale: Dizziness may indicate postural hypotension, requiring preventive education.
A patient with heart failure has tachypnea, severe dyspnea, and a SpO2 of 84%. The nurse identifies a nursing diagnosis of impaired gas exchange related to increased preload and mechanical failure. An appropriate nursing intervention for this diagnosis is
- A. Assist the patient to cough and deep breath every 2 hours
- B. Assess intake and output every 8 hours and weigh daily
- C. Encourage to alternate rest and activity to reduce cardiac workload
- D. Place the patient in a high Fowler's position with the legs horizontal
Correct Answer: D
Rationale: A high fowler's position increases the thoracic capacity, improving ventilation, and sitting with the legs horizontal will decrease venous return.
Nurse's role in hemodynamic monitoring.
- A. Data collection
- B. Interpretation
- C. Both A and B
- D. None of the above
Correct Answer: C
Rationale: Nurses collect data and interpret findings to guide interventions.