A patient presents with excessive thirst, large volumes of dilute urine, and low urine osmolality. Laboratory tests reveal hypernatremia and elevated serum osmolality. Which endocrine disorder is most likely responsible for these symptoms?

Correct Answer: D

Rationale: The correct answer is D: Diabetes insipidus. This condition is characterized by excessive thirst, large volumes of dilute urine, low urine osmolality, hypernatremia, and elevated serum osmolality. The underlying cause is a deficiency in or insensitivity to antidiuretic hormone (ADH), leading to the inability of the kidneys to concentrate urine properly. Hyperthyroidism (choice A) and hypothyroidism (choice B) do not directly affect urine concentration. While diabetes mellitus (choice C) can also present with polyuria and polydipsia, it would typically have high urine osmolality due to the presence of glucose. Therefore, diabetes insipidus is the most likely endocrine disorder responsible for these specific symptoms.

Correct Answer: D

Rationale: The correct answer is D: Ventricular tachycardia. Ventricular tachycardia is a serious arrhythmia that can lead to palpitations, dizziness, and syncope due to the rapid and abnormal heart rhythm originating in the ventricles. This arrhythmia can be life-threatening if not promptly treated. A: Stable angina is characterized by chest discomfort or pain due to reduced blood flow to the heart muscle, usually during physical exertion or stress. It does not typically present with palpitations, dizziness, or syncope. B: Unstable angina is a more severe form of angina where symptoms occur even at rest. While it can lead to serious complications like heart attack, it does not commonly present with palpitations, dizziness, or syncope. C: Atrial fibrillation is a common arrhythmia originating in the atria, leading to an irregular and often rapid heartbeat. While it can cause palpitations and dizziness,

Correct Answer: A

Rationale: The correct answer is A: Pulmonary embolism. This is the most likely cause of the symptoms based on the presentation of chest pain, dyspnea, hemoptysis, and a mismatched defect on the V/Q scan. A pulmonary embolism occurs when a blood clot travels to the lungs, causing a blockage in the pulmonary artery. This can lead to symptoms like chest pain, shortness of breath, and coughing up blood. The V/Q scan showing a mismatched defect indicates a ventilation-perfusion mismatch, which is a classic finding in pulmonary embolism. Pericarditis (B), acute myocardial infarction (C), and aortic dissection (D) typically present with different sets of symptoms and do not match the V/Q scan findings in this case.

Correct Answer: C

Rationale: The correct answer is C because providing emotional support and offering counseling or therapy sessions address the root cause of the patient's depression in a holistic manner. This intervention allows the patient to express their emotions, process their feelings, and receive guidance on coping strategies. Encouraging social activities (A) may not directly address the underlying emotional issues. Referring to a psychiatrist for medication (B) should be considered if counseling alone is insufficient. Exploring spiritual beliefs (D) is important but may not be the most immediate priority for addressing depression in this context.

Correct Answer: D

Rationale: The correct answer is D because referring the patient to a pain management specialist for evaluation is essential in this scenario. The specialist can conduct a comprehensive assessment to identify the underlying causes of the intractable pain and recommend a tailored pain management plan. This approach ensures a multidisciplinary approach to address the complex nature of the patient's pain. Choice A is incorrect because simply increasing the dosage of the current opioid medication may not effectively address the underlying cause of the pain and can lead to potential side effects or opioid tolerance. Choice B is incorrect as switching to a different opioid medication without a thorough evaluation may not guarantee better pain control and can increase the risk of adverse effects or inadequate pain relief. Choice C is incorrect as administering adjuvant analgesic medications without addressing the root cause of the pain may not provide adequate pain relief and does not address the need for a specialized pain management plan.