A patient has been advised to add a nasal spray (an adrenergic decongestant) to treat a cold. The nurse will include which instruction?

Correct Answer: B

Rationale: The correct answer is B: "Limit use of this spray to 3 to 5 days." Adrenergic decongestants, such as nasal sprays, can lead to rebound congestion if used for an extended period. Limiting the use to 3 to 5 days helps prevent this rebound effect. Other choices are incorrect as: A: "You won’t see effects for at least 1 week." - This is incorrect because adrenergic decongestants provide immediate relief. C: "Continue the spray until nasal stuffiness has resolved." - This is incorrect as prolonged use can lead to worsening symptoms. D: "Avoid use of this spray if a fever develops." - This is incorrect as fever is not a contraindication for using adrenergic decongestants.

Correct Answer: A

Rationale: Drug resistance refers to the ability of microbes or cancer cells to withstand the effects of drugs designed to kill or inhibit their growth. This loss of effectiveness is a significant concern in healthcare. Therefore, the statement that drug resistance is a term used to describe the loss of effectiveness of antimicrobial or antitumour drugs is TRUE. Summary of other choices: - B: FALSE - Incorrect, as drug resistance is a real phenomenon affecting the efficacy of drugs. - C: None of the above - Incorrect, as option A is correct. - D: All of the above - Incorrect, as not all options are valid; only option A is correct.

Correct Answer: D

Rationale: The correct answer is D: All of the above. Dibucaine, Lidocaine, and Mepivacaine are all local anesthetics commonly used for infiltrative and regional anesthesia. These agents work by blocking sodium channels, preventing the generation and propagation of action potentials in nerves. They are effective for producing anesthesia in a localized area, making them suitable for procedures like dental work, minor surgeries, and nerve blocks. Each of these local anesthetics has a slightly different onset, duration, and potency, allowing for flexibility in choosing the most appropriate agent based on the specific clinical situation. Therefore, choosing all of the above options is correct as they are all suitable choices for infiltrative and regional anesthesia.

Correct Answer: B

Rationale: The correct answer is B: Hexamethonium. Ganglion-blocking drugs act by blocking nicotinic receptors in autonomic ganglia, leading to decreased sympathetic and parasympathetic responses. Hexamethonium is a ganglion-blocking drug that specifically acts on ganglionic nicotinic receptors. - A: Homatropine is a muscarinic antagonist used to dilate the pupil. - C: Rapacuronium is a non-depolarizing neuromuscular blocking agent. - D: Edrophonium is an acetylcholinesterase inhibitor used for the diagnosis of myasthenia gravis.

Correct Answer: D

Rationale: The correct answer is D: Succinylcholine. Succinylcholine can cause cardiac arrhythmias by inducing hyperkalemia, especially in patients with certain conditions like burns, denervation injuries, or spinal cord injuries. This hyperkalemia can lead to dangerous arrhythmias such as ventricular tachycardia or fibrillation. Vecuronium (A), Tubocurarine (B), and Rapacuronium (C) are not known to cause cardiac arrhythmias as they do not have the same mechanism of action as Succinylcholine.