What is the weight-based dosing for norepinephrine (vasopressor) in post-cardiac arrest hypotension?

Weight-Based Dosing for Norepinephrine in Post-Cardiac Arrest Hypotension

For post-cardiac arrest hypotension, norepinephrine should be initiated at 0.1-0.5 mcg/kg/min, titrated to maintain a mean arterial pressure (MAP) of at least 65 mmHg. 1

Administration Guidelines

Initial Dosing and Titration

• Start norepinephrine at 0.1 mcg/kg/min
• Titrate dose upward by 0.05-0.1 mcg/kg/min every 3-5 minutes based on blood pressure response
• Target MAP of 65 mmHg to ensure adequate organ perfusion
• Usual effective dose range: 0.1-0.5 mcg/kg/min
• Maximum dose rarely exceeds 1.0 mcg/kg/min

Route of Administration

• Central venous access is strongly preferred to minimize risk of extravasation
• Peripheral administration can be used for short-term therapy (<24 hours) with careful monitoring when central access is not immediately available 1

Monitoring Parameters

• Continuous cardiac monitoring is essential
• Frequent blood pressure measurements (every 2-5 minutes initially, then every 15 minutes when stabilized)
• Regular assessment of:
  • Tissue perfusion (capillary refill, urine output)
  • Mental status
  • Skin temperature and color
  • Serum lactate levels

Special Considerations

Volume Status Assessment

• Before initiating norepinephrine, assess and correct hypovolemia
• Consider initial fluid bolus (1-2 L normal saline for adults) if hypovolemia is suspected 1
• Administer fluid bolus at 5-10 mL/kg in first 5 minutes for adults
• Monitor for signs of volume overload in patients with heart failure or renal disease

Potential Adverse Effects

• Tachyarrhythmias
• Increased myocardial oxygen consumption
• Lactic acidosis
• Hyperglycemia
• Tissue necrosis if extravasation occurs 1

Alternative Approaches

If norepinephrine is unavailable or ineffective:

• Epinephrine can be considered at 0.1 mcg/kg/min (range 0.1-1.0 mcg/kg/min) 1
• Dopamine can be used as an alternative at 2-20 mcg/kg/min 1

Common Pitfalls to Avoid

1. Delayed initiation: Post-cardiac arrest hypotension is associated with worse outcomes and should be treated promptly
2. Inadequate volume resuscitation: Failure to correct hypovolemia before starting vasopressors
3. Peripheral administration without monitoring: Increases risk of extravasation and tissue necrosis
4. Failure to titrate: Not adjusting dose based on patient response
5. Inadequate monitoring: Lack of continuous hemodynamic assessment during vasopressor therapy

By following these weight-based dosing guidelines for norepinephrine in post-cardiac arrest hypotension, you can optimize tissue perfusion and improve patient outcomes while minimizing adverse effects.