A patient is undergoing abdominal surgery and has been anesthetized for 3 hours. Which nursing diagnosis would be appropriate for this patient?

Correct Answer: D

Rationale: The correct answer is D: Impaired gas exchange related to central nervous system depression produced by general anesthesia. During abdominal surgery under general anesthesia, the patient's central nervous system is depressed, leading to impaired gas exchange. This is due to decreased respiratory drive and potential airway obstruction. It is essential for the nurse to monitor the patient's respiratory rate, depth, and oxygen saturation to prevent respiratory complications. Choice A (Anxiety related to the use of an anesthetic) is incorrect because anxiety is not a priority nursing diagnosis during surgery under anesthesia. Choice B (Risk for injury related to increased sensorium from general anesthesia) is incorrect as general anesthesia actually decreases sensorium, reducing the risk for injury. Choice C (Decreased cardiac output related to systemic effects of local anesthesia) is incorrect as local anesthesia does not typically affect cardiac output during abdominal surgery under general anesthesia.

Correct Answer: C

Rationale: The correct antidote for heparin overdose is protamine sulfate. Protamine sulfate acts by binding to heparin to form a stable salt complex, neutralizing the anticoagulant effects of heparin. Vitamin E (Choice A) and vitamin K (Choice B) are not antidotes for heparin overdose. Vitamin E is an antioxidant, and vitamin K is essential for blood clotting but is not used as an antidote for heparin. Potassium chloride (Choice D) is used to treat hypokalemia, not heparin overdose. Therefore, the correct choice is protamine sulfate as it directly counteracts the effects of heparin overdose.

Correct Answer: C

Rationale: The correct answer is C: phenytoin (Dilantin) has a significant drug interaction with isoniazid. Phenytoin is a substrate of the enzyme CYP2C9, which is inhibited by isoniazid, leading to increased phenytoin levels and potential toxicity. Pyridoxine (A) is often given with isoniazid to prevent peripheral neuropathy. Penicillins (B) do not have significant interactions with isoniazid. Benzodiazepines (D) are not metabolized through CYP2C9 and therefore do not interact significantly with isoniazid.

Correct Answer: B

Rationale: Correct Answer: B (FALSE) Rationale: 1. Metabolic transformation and conjugation often lead to the inactivation or reduction of a substance's biological activity. 2. Conjugation typically involves adding a polar group to increase the substance's water solubility for excretion. 3. Metabolic transformations can lead to the formation of less active or inactive metabolites. 4. Therefore, the correct answer is FALSE as these processes usually decrease the biological activity of a substance. Summary: - Choice A (TRUE) is incorrect as metabolic transformation and conjugation generally decrease, not increase, a substance's biological activity. - Choice C (All) and Choice D (None) are also incorrect as the correct answer is specifically B, indicating a decrease in biological activity.

Correct Answer: A

Rationale: The correct answer is A: Intermediate chain. The duration of local anesthetic action is mainly determined by the intermediate chain in the structure. The length and structure of the intermediate chain influence the rate of diffusion through tissues and the binding affinity to sodium channels. Lipophilic and ionizable groups do play a role in the mechanism of action of local anesthetics but do not directly affect the duration of action. Therefore, choice A is the most relevant in determining the duration of local anesthetic action compared to the other choices.