CNS Pharmacology USMLE Step 1 Practice Question
A 70-year-old man with a history of hypertension and type 2 diabetes mellitus is brought to the emergency department and subsequently hospitalized for acute decompensated heart failure following a large anterior myocardial infarction confirmed on ECG and troponin elevation. On examination, he is diaphoretic, cool and clammy to the touch, and does not respond to verbal stimulation appropriately. His blood pressure is 78/50 mmHg, heart rate is 118 beats/min, respiratory rate is 26 breaths/min, and oxygen saturation is 88% on room air. Urine output over the past two hours has been less than 10 mL/hr. Right heart catheterization reveals a pulmonary capillary wedge pressure of 24 mmHg and a cardiac index of 1.6 L/min/m². Which of the following intravenous agents would best improve contractility through predominant beta-1 adrenergic receptor agonist activity?
Answer choices
- AClonidine
- BPhenylephrine
- CPropranolol
- DDobutamineCorrect answer
- EAcetylcholine
- FMilrinone
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