Nor%252525252520epinephrine

# Norepinephrine ## Overview Norepinephrine is a potent catecholamine with primary alpha-1 agonist activity (vasoconstriction) and moderate beta-1 agonist activity (inotropic effect). It is the first-line vasopressor for septic shock. ## Primary Indications * Acute hypotensive states (e.g., septic shock, cardiogenic shock). * Refractory hypotension after adequate fluid resuscitation. ## Adult Dosing * **Initial:** 0.05 to 0.1 mcg/kg/min or 2 to 4 mcg/min via continuous IV infusion. * **Titration:** Titrate by 0.05 to 0.5 mcg/kg/min every 3–5 minutes to achieve target Mean Arterial Pressure (MAP), typically ≥65 mmHg. * **Maintenance:** Usual range is 0.01 to 3 mcg/kg/min. * *Note: Dosing is highly dependent on institutional protocol; always follow your local unit-based guidelines.* ## Pediatric Dosing * **Initial:** 0.05 to 0.1 mcg/kg/min by continuous IV infusion. * **Titration:** Titrate as needed to maintain age-appropriate blood pressure. * **Max:** Generally up to 1–2 mcg/kg/min in severe cases. ## Dose Adjustments * **Renal/Hepatic:** No specific dose adjustments provided in manufacturer labeling; monitor for efficacy and peripheral ischemia in patients with severe organ impairment. * **Tapering:** Must be tapered gradually to prevent rebound hypotension. ## Contraindications * Hypersensitivity to norepinephrine or bisulfites. * Use as the sole agent in hypovolemic shock (must be preceded or accompanied by volume replacement). * Avoid administration via peripheral lines if possible (high risk of extravasation necrosis). ## Adverse Effects * **Cardiovascular:** Bradycardia, hypertension, arrhythmias, myocardial ischemia. * **Local:** Extravasation can cause severe tissue necrosis and sloughing (if extravasation occurs, consider phentolamine infiltration). * **Systemic:** Anxiety, tremor, headache, metabolic acidosis (high doses). ## Key Drug Interactions * **MAO Inhibitors / TCAs:** May significantly potentiate the pressor response to norepinephrine, risking severe hypertensive crisis. * **Beta-blockers:** May result in unopposed alpha-adrenergic stimulation (excessive vasoconstriction). * **General Anesthetics (e.g., Halothane/Cyclopropane):** Increased risk of ventricular arrhythmias. ## Monitoring * **Hemodynamics:** Continuous invasive blood pressure monitoring (A-line) preferred; frequent non-invasive BP checks if unavailable. * **Tissue Perfusion:** Heart rate, rhythm, mental status, urine output, and distal limb perfusion/color. * **IV Site:** Assess hourly for signs of extravasation (pallor, coldness, local pain). ## Clinical Pearls * **Line Compatibility:** Central venous catheter is preferred to avoid skin necrosis. If peripheral administration is required, use a large-bore proximal vein and limit duration/concentration. * **Stability:** Norepinephrine is light-sensitive; infusion bags should be protected or observed for discoloration (discontinue if pink/brown). * **Potency:** Extremely potent; use a dedicated line and a calibrated infusion pump to ensure accurate titration. *** *Disclaimer: This information is for educational purposes only. Always consult current institutional protocols and the manufacturer’s package insert for the most accurate and up-to-date prescribing information.*