Nokea
Organophosphate insecticides and nerve gases exert their lethal effects by:
- A. Blocking alpha and β-adrenergic receptors
- B. Blocking all muscarinic receptors on target cells
- C. Blocking nicotinic receptors in the brain
- D. Inhibiting acetylcholine metabolism
Correct Answer: D
Rationale: The correct answer is D because organophosphate insecticides and nerve gases inhibit acetylcholine metabolism by irreversibly binding to acetylcholinesterase enzyme, leading to accumulation of acetylcholine at synapses. This results in overstimulation of cholinergic receptors, causing symptoms of cholinergic toxicity.
Choice A is incorrect because alpha and beta-adrenergic receptors are not the targets of organophosphates. Choice B is incorrect because organophosphates do not block all muscarinic receptors. Choice C is incorrect because organophosphates do not specifically target nicotinic receptors in the brain.
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Simple goiter can be prevented by _________.
- A. antibiotics
- B. adding iodine to the diet
- C. surgery
- D. hormone therapy
Correct Answer: B
Rationale: The correct answer is B: adding iodine to the diet. Iodine deficiency is a common cause of simple goiter. Iodine is essential for the production of thyroid hormones, and a lack of it can lead to the enlargement of the thyroid gland. Adding iodine to the diet helps prevent simple goiter by ensuring the thyroid has enough iodine to function properly. Antibiotics (choice A) are not effective for preventing goiter as it is not caused by bacteria. Surgery (choice C) and hormone therapy (choice D) are typically used to treat goiter once it has developed, not prevent it.
In a patient with central diabetes insipidus, what will the administration of ADH during a water deprivation test result in?
- A. Decrease in body weight
- B. Decrease in blood pressure
- C. Increase in urinary output
- D. Increase in urine osmolality
Correct Answer: D
Rationale: In central diabetes insipidus, administering ADH during a water deprivation test will result in an increase in urine osmolality due to the kidneys' ability to concentrate urine in response to ADH.
Concerning catecholamines, all the following are true EXCEPT:
- A. They contain a catechol nucleus
- B. They act directly on the receptor
- C. Have a short duration of action
- D. Include ephedrine and amphetamine
Correct Answer: D
Rationale: The correct answer is D because ephedrine and amphetamine are not catecholamines. A is correct as catecholamines contain a catechol nucleus. B is true as they act directly on receptors. C is also true since catecholamines have a short duration of action. Therefore, D is the incorrect statement as ephedrine and amphetamine do not fall under the category of catecholamines due to their chemical structure and mode of action.
Mr. M has just had a subtotal thyroidectomy. During the first 12 hours postoperatively, which of the following should be included in his nursing care?
- A. Instructing the patient to avoid moving the head
- B. Monitoring for signs of hemorrhage and shock
- C. Administering medications to reduce thyroid hormone levels
- D. Preparing the patient for thyroid replacement therapy
Correct Answer: B
Rationale: Postoperative care after a thyroidectomy focuses on monitoring for complications like hemorrhage, which can be life-threatening.
You are caring for a diabetic patient who is developing DKA. Which delegated task is most appropriate?
- A. Ask the unit clerk to page the physician to come to the unit.
- B. Ask the LPN/LVN to administer IV insulin according to the sliding scale.
- C. Ask the nursing assistant to check the patient's level of consciousness.
- D. Ask the nursing assistant to get the patient a cup of orange juice.
Correct Answer: C
Rationale: Checking the patient's level of consciousness is a crucial assessment for a patient developing DKA, and this task can be delegated to the nursing assistant.