Correct Answer: B

Rationale: In a client who is vomiting, the loss of gastric fluid containing hydrochloric acid can lead to metabolic alkalosis. Metabolic alkalosis is caused by the loss of acids such as hydrochloric acid from the body. Therefore, in this scenario, the nurse should assess the client for metabolic alkalosis. Choices A, C, and D are incorrect because vomiting does not typically lead to metabolic acidosis, respiratory acidosis, or respiratory alkalosis.

Correct Answer: D

Rationale: The correct answer is D. The desired action of oral contraceptives can be reduced when taken with tetracyclines like doxycycline. Therefore, patients on oral contraceptives should be advised to use a backup contraception method while taking doxycycline. Choice A is incorrect because nausea and vomiting are common adverse effects of doxycycline. Choice B is incorrect because doxycycline is not known for causing teratogenic effects. Choice C is incorrect because dairy products can interfere with the absorption of doxycycline, so they should be avoided when taking this medication.

Correct Answer: C

Rationale: The correct answer is C: Tachypnea, dizziness, and paresthesias. When a client is anxious, they may hyperventilate, leading to respiratory alkalosis. Tachypnea (rapid breathing) is a common sign of respiratory alkalosis. Dizziness and paresthesias (tingling or numbness in the extremities) are also typical symptoms. Choices A, B, and D are incorrect. Disorientation and dyspnea (Choice A) are not specific signs of respiratory alkalosis. Drowsiness, headache, and tachypnea (Choice B) may be more indicative of other conditions. Dysrhythmias and decreased respiratory rate and depth (Choice D) are not consistent with the expected signs of respiratory alkalosis.

Correct Answer: C

Rationale: In teaching a client about self-catheterization, it is essential to emphasize proper hand hygiene before and after the procedure to prevent infections. Using lubricant on the catheter helps with insertion and reduces discomfort. Therefore, statements A and B are correct and should be included in the client's teaching. Option D is incorrect because self-catheterization frequency should be individualized based on the client's needs, and a specific time frame like every 12 hours may not be suitable for everyone. Choosing a smaller lumen catheter is preferred over a larger one. Self-catheterization should not be limited to a specific time frame but should be based on the individual's needs and voiding patterns. Therefore, option C is the correct choice as it includes the two essential statements for teaching self-catheterization in the home setting.

Correct Answer: B

Rationale: A CD4+ count of 450 cells/L is below the normal range (500-1600 cells/mcL), indicating a decline in immune function in the client. Antiretroviral therapy is recommended when the CD4+ count falls below 500 cells/mcL or below 25%, or when the client displays symptoms of HIV. Therefore, the interpretation of this test result suggests that the client requires antiretroviral therapy to manage the HIV infection. Choices A, C, and D are incorrect because a CD4+ count of 450 cells/L does not signify improvement, discontinuation of therapy, or an effective response to treatment for HIV.