Nokea
The following sympathomimetic drug is a catecholamine:
- A. Ephedrine
- B. Phenylephrine
- C. Phentolamine
- D. Isoprenaline
Correct Answer: D
Rationale: Step-by-step rationale for why D (Isoprenaline) is the correct answer:
1. Isoprenaline is a catecholamine because it has a catechol structure, which consists of a benzene ring with two hydroxyl groups.
2. Catecholamines are a class of neurotransmitters that include dopamine, norepinephrine, and epinephrine.
3. Isoprenaline acts as a non-selective beta-adrenergic agonist, stimulating both beta-1 and beta-2 adrenergic receptors.
4. Its pharmacological effects include increased heart rate, bronchodilation, and vasodilation.
Summary of why other choices are incorrect:
A. Ephedrine is a sympathomimetic drug but is not a catecholamine as it lacks the catechol structure.
B. Phenylephrine is a sympathomimetic drug that acts as an alpha-adrenergic agonist,
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The nurse has identified the nursing diagnosis of fatigue for a patient who is hypothyroid. What should the nurse do while caring for this patient?
- A. Monitor for changes in orientation, cognition, and behavior.
- B. Monitor for vital signs and cardiac rhythm response to activity.
- C. Monitor bowel movement frequency, consistency, shape, volume, and color.
- D. Assist in developing well-balanced meal plans consistent with level of energy expenditure.
Correct Answer: B
Rationale: Hypothyroid patients often experience fatigue due to a slowed metabolic rate, so it's essential to monitor vital signs and cardiac response to physical activity to assess for complications.
Propranolol produces all of the following actions EXCEPT:
- A. Negative inotropic effect
- B. Negative chronotropic effect
- C. Slowing of A-V conduction
- D. Bronchodilation in asthmatic patients
Correct Answer: D
Rationale: Propranolol is a non-selective beta-blocker which primarily affects the heart. Bronchodilation is not a common effect of propranolol due to its non-selectivity for beta-2 receptors in the lungs. Therefore, choice D is the correct answer. Choices A, B, and C are correct because propranolol typically causes negative inotropic effect (reduced force of heart contraction), negative chronotropic effect (slowing of heart rate), and slowing of A-V conduction (delay in electrical signal between atria and ventricles), respectively.
Verapamil is a drug used for treating hypertension. It should be used with caution with other drugs that can depress heart rate or contractility. Which drug, if given with verapamil, might therefore cause the greatest risk of depressing heart rate, contractile force, or impulse conduction?
- A. Albuterol
- B. Scopolamine
- C. Propranolol
- D. Isoproterenol
Correct Answer: C
Rationale: The correct answer is C: Propranolol. Verapamil is a calcium channel blocker that can depress heart rate and contractility. Propranolol is a beta-blocker that also decreases heart rate and contractile force. When combined, both drugs can have an additive effect leading to a significant decrease in heart rate and contractility, potentially causing bradycardia or heart failure.
Albuterol (A) is a beta-2 agonist that actually increases heart rate and contractility. Scopolamine (B) is an anticholinergic drug that may decrease heart rate, but its effect is not as significant as propranolol. Isoproterenol (D) is a beta agonist that increases heart rate and contractility, so its combination with verapamil would not pose the same risk as propranolol.
Which is a water soluble vitamin?
- A. D
- B. B12
- C. A
- D. K
Correct Answer: B
Rationale: The correct answer is B: B12. Vitamin B12 is water-soluble because it dissolves in water, allowing it to be easily absorbed and transported in the bloodstream. It plays a crucial role in nerve function, red blood cell production, and DNA synthesis. Vitamins D, A, and K are fat-soluble vitamins, meaning they are absorbed along with fats in the diet and are stored in the body's fat tissues. Since they are not water-soluble, they require bile for absorption and are stored in the body for longer periods. Hence, B12 is the only water-soluble vitamin among the given choices.
Mr. Johnson received his first dose of Lente insulin at 7:30 A.M. When should he be observed for signs of hypoglycemia?
- A. 10-11 A.M.
- B. 4-6 P.M.
- C. Between 2 A.M. and breakfast
- D. Immediately after the injection
Correct Answer: B
Rationale: Lente insulin has an onset of action that typically peaks 4-6 hours after injection, so this is when signs of hypoglycemia are most likely to occur.