When starting a patient on antidysrhythmic therapy, the nurse will remember that which problem is a potential adverse effect of any antidysrhythmic drug?

Correct Answer: D

Rationale: The correct answer is D: Dysrhythmias. Antidysrhythmic drugs can potentially cause new or worsened dysrhythmias as an adverse effect due to their mechanism of action on cardiac electrophysiology. This can lead to serious complications such as ventricular tachycardia or fibrillation. A: Deficiency of fat-soluble vitamins - Antidysrhythmic drugs do not typically cause this adverse effect. B: Hyperkalemia - While some drugs may affect potassium levels, dysrhythmias are a more direct and common adverse effect of antidysrhythmic drugs. C: Heart failure - While some drugs may exacerbate heart failure in certain situations, dysrhythmias are a more immediate concern with antidysrhythmic therapy.

Correct Answer: A

Rationale: The correct answer is A: Renal tubules. Biological barriers are structures that prevent the entry of harmful substances into the body. Renal tubules are not considered a biological barrier as they are involved in the filtration and reabsorption of substances within the body, rather than acting as a physical barrier. Cell membranes, capillary walls, and the placenta are all examples of biological barriers as they selectively control the passage of substances into and out of cells, tissues, and organs to maintain homeostasis. Therefore, the renal tubules do not fit the criteria of a biological barrier, making option A the correct answer.

Correct Answer: C

Rationale: The correct answer is C, Abstinence Syndrome. This term refers to the occurrence of psychological and somatic disturbances when a drug is suddenly discontinued after prolonged use. Tachyphylaxis (A) is the rapid development of tolerance to a drug. Sensibilization (B) is the opposite of tolerance, where increased sensitivity to a drug occurs over time. Idiosyncrasy (D) is an unexpected or unusual reaction to a drug. In this scenario, the situation describes the consequences of stopping the drug, aligning with the definition of Abstinence Syndrome.

Correct Answer: C

Rationale: The correct answer is C because cocaine actually causes myocardial stimulation and vasoconstriction, not depression and vasodilatation. Cocaine is a local anesthetic and vasoconstrictor, commonly used in nose and throat procedures (Choice A). Its abuse potential limits its medical use (Choice B). Cocaine causes sympathetically mediated effects such as tachycardia and vasoconstriction (Choice D). Therefore, the incorrect statement is C because cocaine does not cause myocardial depression and peripheral vasodilatation.

Correct Answer: A

Rationale: The correct answer is A: Eye. The parasympathetic nervous system controls functions like pupil constriction in the eye. This effect is mediated by the neurotransmitter acetylcholine. The eye has a unique structure called the iris sphincter muscle, which responds to parasympathetic stimulation by constricting the pupil. Unlike other organs, the effect on the eye is not subject to rapid decline, as the iris sphincter muscle has a high sensitivity to acetylcholine. Therefore, the parasympathetic function in the eye does not decline rapidly compared to other organs. Summary of other choices: B: Heart - Parasympathetic control of heart rate can decline rapidly due to factors like decreased acetylcholine release. C: Smooth muscle organs - Parasympathetic control of smooth muscle organs can also decline rapidly due to factors like receptor desensitization. D: Glands - Parasympathetic control of glands can