What is the primary effect of a calcium channel blocker on the heart?
- A. Decreases heart rate
- B. Increases heart rate
- C. Increases blood pressure
- D. Decreases blood pressure
Correct Answer: D
Rationale: The primary effect of a calcium channel blocker on the heart is to decrease blood pressure. Calcium channel blockers block the entry of calcium into the smooth muscle cells of blood vessels and the heart. This causes vasodilation and reduces the force of contraction in the heart, leading to a decrease in blood pressure. Choices A and B are incorrect as calcium channel blockers typically do not directly affect heart rate. Choice C is incorrect because calcium channel blockers actually tend to lower blood pressure rather than increase it.
You may also like to solve these questions
What procedure uses a catheter to open blocked coronary arteries and improve blood flow to the heart muscle?
- A. Angioplasty
- B. Stent placement
- C. Coronary artery bypass graft (CABG)
- D. Valve replacement
Correct Answer: A
Rationale: The correct answer is A: Angioplasty. Angioplasty involves using a catheter with a balloon to open blocked coronary arteries, improving blood flow to the heart muscle. The balloon is inflated to compress the plaque against the artery walls, restoring blood flow. Stent placement (B) involves inserting a mesh tube to keep the artery open after angioplasty. CABG (C) is a surgical procedure that uses grafts to bypass blocked coronary arteries. Valve replacement (D) is a procedure to replace damaged heart valves, not specifically for opening blocked coronary arteries.
Which test measures how well the lungs work by assessing the amount of air the lungs can hold and how quickly air can be exhaled?
- A. Spirometry
- B. Pulse oximetry
- C. Arterial blood gas (ABG)
- D. Chest X-ray
Correct Answer: A
Rationale: The correct answer is A: Spirometry. Spirometry measures lung function by evaluating lung capacity and airflow. It assesses vital parameters like Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 second (FEV1), providing valuable insights into lung health. Pulse oximetry (B) measures oxygen saturation, not lung function. Arterial blood gas (C) evaluates blood oxygen and carbon dioxide levels, not lung capacity. Chest X-ray (D) shows lung structure, not lung function. Therefore, Spirometry is the most appropriate test for assessing lung function.
Mr. Olds is admitted with constrictive pericarditis. He complains of chest pain and receives morphine as ordered. Pain relief for this patient is also facilitated by
- A. Sitting forward
- B. Lying supine
- C. Taking deep breaths
- D. Coughing
Correct Answer: A
Rationale: Sitting forward reduces pressure on the heart.
What is the patient with primary hypertension likely to report?
- A. No symptoms
- B. Cardiac palpitations
- C. Dyspnea on exertion
- D. Dizziness and vertigo
Correct Answer: A
Rationale: Primary hypertension often lacks overt symptoms.
Which of the following is a central vasoconstrictor and peripheral vasodilator?
- A. Parasympathetic nervous system
- B. Sympathetic nervous system
- C. Dopamine
- D. Epinephrine
Correct Answer: D
Rationale: The correct answer is D: Epinephrine. Epinephrine acts as a central vasoconstrictor by constricting blood vessels in vital organs to redirect blood flow to muscles during fight-or-flight response. It also acts as a peripheral vasodilator by dilating blood vessels in skeletal muscles to increase oxygen delivery. Parasympathetic nervous system (A) mainly promotes relaxation, sympathetic nervous system (B) typically causes vasoconstriction, and dopamine (C) has limited vasoactive effects.