norepinephrine (levophed)

The First-Line Workhorse

First-line vasopressor for septic shock, cardiogenic shock, and HRS-AKI in Canadian ICUs. Provides both vasoconstriction (${\alpha }_1$) and inotropy (${\beta }_1$).

• Mechanism: Potent ${\alpha }_1$-agonist (vasoconstriction). Modest ${\beta }_1$-agonist (inotropy/chronotropy).

• Dosing: General: Titrate to MAP > 65. No “ceiling” dose. HRS-AKI: $0.5–3\text{ mg/hr}$ (or $8–50\mu \text{g/min}$) titrated to raise MAP by $10–15\text{ mmHg}$ or target $>65\text{ mmHg}$.

• PK: Onset: 1–2 mins. Half-life: < 5 mins. Metabolism: MAO and COMT.

indications

• Septic Shock – First-line
• Cardiogenic Shock – First-line (to restore coronary perfusion pressure)
• HRS-AKI – First-line in Canadian ICUs (as Terlipressin unavailable)

evidence & efficacy

• Cardiogenic Shock: Superior to Dopamine (lower mortality and arrhythmias)
• Septic Shock: Preferred over Epinephrine for shock maintenance (less metabolic disturbance)
• HRS-AKI: Meta-analyses suggest non-inferiority to Terlipressin for HRS reversal, with lower risk of respiratory failure

cautions

• Extravasation: Causes tissue necrosis. Antidote: Phentolamine
• Hypovolemia: Will clamp down on an empty tank; ensure preload is optimized

related pages: Hepatorenal syndrome (HRS-AKI)