Adrenergic Agonists

A 58-year-old man with a 10-year history of type 2 diabetes mellitus presents to the emergency department with acute onset severe hypotension (BP 70/45 mmHg) and altered mental status following a bout of acute gastroenteritis with profuse diarrhea and vomiting. Physical examination reveals cold, clammy extremities, weak peripheral pulses, and poor capillary refill. Urine output has dropped to 0.3 mL/kg/hr. After rapid fluid resuscitation with 2 L of normal saline, BP remains 78/48 mmHg. Which of the following adrenergic agonists would be the most appropriate choice for this patient at this stage?

A 68-year-old man with severe septic shock and refractory hypotension (SBP 70 mmHg despite adequate fluid resuscitation and low-dose noradrenaline) is admitted to the ICU. Which adrenergic agonist is the drug of choice to add as a second-line vasopressor in this scenario?

A 58-year-old man with acute decompensated heart failure and hypotension (BP 85/55 mmHg, CI 2.0 L/min/m²) is admitted to the ICU. Regarding the selection of inotropic agents, all of the following statements are correct EXCEPT:

A 42-year-old woman with a history of severe asthma is brought to the emergency department in acute respiratory distress. She is wheezing bilaterally, SpO₂ is 82% on room air, and peak expiratory flow is severely reduced. She has received nebulized salbutamol (albuterol) twice in the past 2 hours without adequate response. Her blood pressure is 105/68 mmHg and heart rate is 118 bpm. Intravenous corticosteroids and magnesium sulfate have been initiated. The attending physician decides to administer a subcutaneous injection of an adrenergic agonist for acute bronchospasm relief. Which agent is most appropriate?

Regarding the pharmacological properties of adrenergic agonists, all of the following statements are correct EXCEPT: