A 62-year-old man is admitted to the ICU, intubated and on assist-control ventilation. He is receiving a continuous norepinephrine infusion via a central line to maintain mean arterial pressure. During evening rounds, shortly after receiving a new antibiotic, the patient develops sudden diffuse urticaria, facial and lip angioedema, and his blood pressure falls from 85/50 mmHg to 60/30 mmHg despite the ongoing norepinephrine. His peak inspiratory pressures rise acutely from 20 cm H₂O to 45 cm H₂O, and wheezing is noted on auscultation. Which finding most specifically indicates anaphylactic shock and necessitates immediate intravenous epinephrine administration?

A 45-year-old man in the ICU for sepsis is receiving norepinephrine 0.05 mcg/kg/min via a central line. Shortly after starting a new IV antibiotic, he develops widespread urticaria, facial angioedema, and diffuse wheezing. His blood pressure falls from 110/70 mmHg to 75/40 mmHg, and his heart rate rises from 90 to 125 bpm. Which of the following pharmacologic interventions is the most critical initial step in management?

A 60-year-old, 80 kg man is admitted to the intensive care unit following cardiac catheterization. He is on assist-control mechanical ventilation and a norepinephrine infusion. During evening rounds, he suddenly develops diffuse urticaria, angioedema, and severe bronchospasm with wheezing audible despite ventilator settings. His blood pressure falls from 100/60 mmHg to 70/40 mmHg, heart rate rises from 85 to 120 bpm, and SpO₂ decreases from 98% to 88% on 60% FiO₂. An acute hypersensitivity reaction is suspected. Considering this patient’s critical status and suspected anaphylaxis, which of the following is the most appropriate immediate pharmacologic intervention?

A 62-year-old man with a history of hypertension managed with metoprolol and well-controlled asthma is in the critical care unit following a severe allergic reaction. He is intubated and on assist-control ventilation due to refractory bronchospasm and hypoxemia. Despite receiving two doses of intramuscular epinephrine (0.5 mg each, 5 minutes apart) and continuous albuterol nebulization, his wheezing persists, and his oxygen saturation remains at 88% on an FiO2 of 0.8. His blood pressure is 85/50 mmHg, and heart rate is 110 bpm. A central venous catheter is in place. Considering the patient’s current pharmacotherapy and persistent symptoms, which of the following is the MOST appropriate next pharmacologic intervention to prioritize?

A 45-year-old man intubated and mechanically ventilated in the ICU for ARDS is receiving a norepinephrine infusion via a central line. Five minutes after starting an IV vancomycin infusion, he develops sudden hypotension (BP falls from 110/70 to 75/40 mmHg), diffuse urticaria, facial angioedema, increasing peak inspiratory pressures, tachycardia (HR 130 bpm), and hypoxia (SpO₂ 88% on FiO₂ 0.8). What is the most appropriate immediate first-line pharmacotherapy?

A 62-year-old man receiving a new antibiotic suddenly develops generalized urticaria, angioedema, diffuse wheezing, and severe hypotension (mean arterial pressure falls from 75 to 40 mm Hg). His oxygen saturation decreases to 85% despite 100% FiO₂. Which of the following is the most appropriate initial pharmacologic intervention?

A 45-year-old man with severe pneumonia is on assist-control mechanical ventilation and a continuous norepinephrine infusion via a central line. He acutely develops stridor, diffuse urticaria, and angioedema of the face and neck. His blood pressure falls from 110/70 mmHg to 80/45 mmHg, and ventilator peak airway pressures sharply increase. These findings are consistent with an acute anaphylactic reaction to a newly started antibiotic. Which pharmacologic intervention is the most critical initial step?

A 45-year-old man, intubated and on assist-control ventilation for acute respiratory distress syndrome, develops sudden-onset generalized urticaria, angioedema, and hypotension (BP 70/40 mm Hg, HR 130 bpm) shortly after receiving a scheduled antibiotic infusion through his central venous catheter. The critical care team immediately administers 0.5 mg intramuscular epinephrine to the lateral thigh. Which of the following parameters is most critical for assessing the immediate therapeutic and adverse effects of the administered epinephrine?

A 45-year-old man receiving a norepinephrine infusion via a central venous catheter develops diffuse urticaria, angioedema, and severe bronchospasm with hypotension (BP 60/30 mmHg) and tachycardia (HR 130 bpm) immediately after a new antibiotic infusion. He is intubated and mechanically ventilated. What is the most appropriate initial pharmacologic intervention?

A 45-year-old, 70-kg man is admitted to the intensive care unit after developing a severe hypersensitivity reaction to a newly administered antibiotic. He is intubated and on mechanical ventilation (pressure-regulated volume control) due to refractory bronchospasm and angioedema. Despite receiving three doses of intramuscular epinephrine (0.5 mg every 5 minutes), his blood pressure remains 70/40 mmHg with a heart rate of 130 beats/minute. A central venous catheter is in place, and a norepinephrine infusion is running at 0.1 mcg/kg/min. His lactate is 6 mmol/L. Given the patient’s persistent hemodynamic instability and respiratory compromise, which of the following interventions is most appropriate to initiate at this time?