Early Angiotensin II in the Emergency Department

Following informed consent, patients will receive intravenous angiotensin II (AT-II) infusion for blood pressure support. The patient will remain on the AT-II infusion for 60 minutes prior to determining patient response which will be determined by recording the concurrent dose of norepinephrine and MAP every 10 minutes from initiation. If a positive response (e.g., norepinephrine dose reduction) is witnessed, the AT-II infusion will be titrated off after a maximum of 6 hours or when infusion is completed, whichever occurs first.

Inclusion criteria

• Age ≥18; and
• Requiring norepinephrine at a dose of 0.05-0.25 mcg/kg/min mcg/kg/minute despite adequate fluid resuscitation; and
• Receiving intravenous antibiotics or clinician's intention to administer antibiotics at the time of enrollment; and
• Can provide written informed consent (or legally authorized representative).

Exclusion criteria

• Acute coronary syndrome;
• Cardiogenic shock;
• Patients with a history of mesenteric ischemia;
• Patients with a history of having an aortic dissection or abdominal aortic aneurysm;
• Patients with an expected lifespan of <12 hours;
• Patients with hemorrhagic shock (e.g., actively receiving transfusion of packed red blood cells);
• Active administration of two vasoactive agents before enrollment; and
• Pre-existing thromboembolic disease or inability to tolerate pharmacologic VTE prophylaxis.