Nokea
Neostigmine is a drug useful in the treatment of myasthenia gravis, but it causes parasympathomimetic effects unless another drug is given first. This drug is:
- A. Atropine
- B. Epinephrine
- C. Isoproterenol
- D. Edrophonium
Correct Answer: A
Rationale: The correct answer is A: Atropine. Neostigmine is a cholinesterase inhibitor that increases acetylcholine levels leading to parasympathomimetic effects. Atropine, an anticholinergic drug, blocks the effects of acetylcholine, preventing excessive stimulation of cholinergic receptors. Administering atropine before neostigmine helps counteract the parasympathomimetic effects, making it a necessary pre-treatment. Epinephrine and isoproterenol are adrenergic drugs and wouldn't counteract the cholinergic effects of neostigmine. Edrophonium is another cholinesterase inhibitor like neostigmine, so it wouldn't be effective in preventing the parasympathomimetic effects.
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Individualized nutrition therapy for patients using conventional, fixed insulin regimens should include teaching the patient to
- A. eat regular meals at regular times.
- B. restrict calories to promote moderate weight loss.
- C. eliminate sucrose and other simple sugars from the diet.
- D. limit saturated fat intake to 30% of dietary calorie intake.
Correct Answer: A
Rationale: Patients with fixed insulin regimens should eat regular meals to match insulin action and prevent hypoglycemia.
What are two effects of hypokalemia on the endocrine system?
- A. Decreased insulin and aldosterone release
- B. Decreased glucagon and increased cortisol release
- C. Decreased release of atrial natriuretic factor and increased ADH release
- D. Decreased release of parathyroid hormone and increased calcitonin release
Correct Answer: C
Rationale: Hypokalemia can lead to decreased release of atrial natriuretic factor and increased ADH release as the body attempts to balance sodium and fluid levels.
Calcium level in the blood is regulated by the:
- A. Thyroid
- B. Parathyroid
- C. Adrenal medulla
- D. Both A & B
Correct Answer: D
Rationale: The correct answer is D: Both A & B. The thyroid and parathyroid glands work together to regulate calcium levels in the blood. The parathyroid gland releases parathyroid hormone, which increases calcium levels, while the thyroid gland secretes calcitonin, which decreases calcium levels. Therefore, both glands play a crucial role in maintaining calcium homeostasis. Choice A, the thyroid gland, is incorrect as it primarily regulates metabolism. Choice C, the adrenal medulla, is incorrect as it is responsible for releasing adrenaline and noradrenaline, not regulating calcium levels.
A 34-year-old carpenter presents to the emergency room after an accident in which he inadvertently chopped off the tip of his index finger. He is taken to the operating room for reattachment of the digit, and after sedation, a local anesthetic is administered around the site of the injury. The local anesthetic used in the procedure did not contain any epinephrine, as it usually does for most surgical procedures. The reason for this is
- A. Epinephrine causes increased blood loss during delicate surgery
- B. Epinephrine causes swelling of the tissues, making surgery more challenging
- C. Epinephrine is contraindicated in emergency surgery
- D. Epinephrine causes vasoconstriction, which can lead to vascular ischemia in digits
Correct Answer: D
Rationale: The correct answer is D. Epinephrine causes vasoconstriction, which can lead to vascular ischemia in digits. In delicate surgeries like finger reattachment, maintaining adequate blood flow is crucial for successful outcomes. Using epinephrine can constrict blood vessels excessively, leading to reduced blood supply and potential tissue damage. This can result in vascular ischemia, compromising the viability of the reattached finger.
Explanation for incorrect choices:
A: Epinephrine actually helps in reducing blood loss by constricting blood vessels.
B: Epinephrine reduces tissue swelling, making surgery easier.
C: Epinephrine is not contraindicated in emergency surgery; it is often used to control bleeding and prolong anesthesia.
The body’s major metabolic hormone is released from the:
- A. Pituitary
- B. Thyroid
- C. Thymus
- D. Hypothalamus
Correct Answer: B
Rationale: The correct answer is B: Thyroid. The body's major metabolic hormone, thyroxine (T4) and triiodothyronine (T3), is released from the thyroid gland. The thyroid gland plays a crucial role in regulating metabolism. Pituitary (A) releases various hormones but not the major metabolic hormone. Thymus (C) is responsible for immune function, not metabolism. Hypothalamus (D) regulates the pituitary gland but does not directly release the major metabolic hormone.