Your adult patient is experiencing symptomatic bradycardia with a heart rate of 40 bpm. Once on the monitor, it reveals the patient has a complete third-degree atrioventricular block and is found to be hypotensive as well. Which of the following medications should be avoided, if possible?

Correct Answer: D

Rationale: The correct answer is D: Atropine. In a patient with symptomatic bradycardia due to complete third-degree AV block, atropine should be avoided if possible because it works by blocking the parasympathetic nervous system, potentially worsening the AV block. The first-line treatment for symptomatic bradycardia with hypotension in this scenario is transcutaneous pacing or external temporary pacing. If atropine is ineffective or contraindicated, other options like dopamine, dobutamine, or epinephrine may be considered to support blood pressure until more definitive treatment can be initiated. Dopamine and dobutamine can help increase heart rate and improve cardiac output, while epinephrine can provide inotropic and chronotropic support. However, these medications should be used cautiously and in consultation with a specialist due to the risk of exacerbating the AV block.

Correct Answer: C

Rationale: The correct answer is C: Kussmaul respirations. In diabetic ketoacidosis, the body attempts to compensate for the metabolic acidosis by increasing the respiratory rate and depth, leading to Kussmaul respirations characterized by deep, rapid, and labored breathing. This pattern helps to blow off excess CO2 and decrease the acidity in the blood. Bradypnea (A) is slow breathing, which is not characteristic of the compensatory response in diabetic ketoacidosis. Central neurogenic hyperventilation (B) involves rapid and deep breathing due to neurological issues, not commonly seen in diabetic ketoacidosis. Cheyne-Stokes respirations (D) are characterized by periods of deep breathing followed by periods of apnea, which is not typically associated with diabetic ketoacidosis.

Correct Answer: B

Rationale: Step 1: Chest pain that is not changed or relieved by oxygen therapy alone is a key indicator of acute myocardial infarction (MI). Step 2: In a suspected MI, the lack of improvement with oxygen therapy suggests a cardiac origin for the chest pain. Step 3: Oxygen therapy may alleviate chest pain related to respiratory issues, but not typically in cases of cardiac origin. Step 4: This lack of response to oxygen therapy indicates the need for further evaluation and treatment for a suspected MI. Summary: Choices A, C, and D are incorrect because they do not specifically address the characteristic of chest pain in relation to oxygen therapy, which is a crucial differentiating factor in identifying a potential acute MI.

Correct Answer: B

Rationale: The correct answer is B (80-110 mg/dL) as per the American Heart Association guidelines. It is considered the optimal range for glucose concentration to prevent hypoglycemia and hyperglycemia. Choice A (60-90 mg/dL) is too low and can lead to hypoglycemia. Choice C (186-202 mg/dL) and D (110-160 mg/dL) are too high and can increase the risk of hyperglycemia and complications. Staying within the recommended range helps maintain stable blood sugar levels and reduces the risk of adverse events.

Correct Answer: A

Rationale: Rationale for Correct Answer (A): 1. Children's spinal cords are more flexible than adults', increasing risk of injury without x-ray abnormalities. 2. Pediatric spinal injuries may not show on x-ray initially, requiring further imaging. 3. This phenomenon is known as SCIWORA (spinal cord injury without radiographic abnormality). 4. In contrast, adults' spinal cords are less flexible, often leading to visible abnormalities on x-ray. Summary of Incorrect Choices: B: Hypotension in infants with TBI is usually due to other factors like hemorrhage, not cerebral edema. C: Methylprednisolone is not recommended for initial therapy in pediatric TBI due to lack of proven benefit. D: Children more commonly have diffuse axonal injury rather than focal mass lesions in TBI compared to adults.