How to administer noradrenaline (norepinephrine) for hypotension?

How to Administer Noradrenaline (Norepinephrine) for Hypotension

Norepinephrine should be administered through a central venous line whenever possible, with an initial dose of 0.25-0.375 mL/min (8-12 mcg/min), titrated to maintain a mean arterial pressure of 65-100 mmHg. 1, 2

Preparation and Administration

• Norepinephrine is available as 4 mg/4 mL (1 mg/mL) solution in single-dose vials 2
• Administer through a central venous line whenever possible to prevent tissue necrosis from extravasation 1, 3
• If central access is unavailable, peripheral administration may be considered for:
  • Low doses (<20 mcg/min) 4
  • Short duration (<24 hours) 5
  • Using a large-bore catheter (18G or larger) placed at or above the antecubital fossa 4

Dosing Protocol

• Initial dose: 0.25-0.375 mL/min (8-12 mcg/min) 2
• Maintenance dose: Average range is 0.0625-0.125 mL/min (2-4 mcg/min) 2
• Titrate to achieve a target mean arterial pressure (MAP) of 65-100 mmHg, sufficient to maintain vital organ perfusion 1, 3
• For refractory hypotension, consider escalating the dose or adding alternative vasopressors 1

Monitoring Requirements

• Continuous hemodynamic monitoring is essential during administration 1
• Assess peripheral perfusion regularly (skin temperature, capillary refill) 1
• Monitor for signs of extravasation, especially with peripheral administration 1, 2
• Evaluate markers of tissue perfusion (lactate clearance, urine output, mental status) 3

Managing Extravasation

• If extravasation occurs, immediately infiltrate 5-10 mg of phentolamine diluted in 10-15 mL of saline into the site 1, 2
• Infiltration should be performed within 12 hours for best results 2
• Sympathetic blockade with phentolamine causes immediate local hyperemic changes 2

Discontinuation

• Never stop norepinephrine infusion abruptly as it may result in marked hypotension 2
• Decrease the dose by 25% of the current dose every 30 minutes as tolerated 1
• When discontinuing, gradually reduce the infusion rate while expanding blood volume with intravenous fluids 2

Clinical Considerations and Precautions

• Correct volume depletion before or concurrently with norepinephrine administration 3
• Norepinephrine is indicated for severe hypotension (e.g., systolic BP ≤70 mmHg) with low peripheral vascular resistance 1, 3
• Use cautiously in patients with ischemic heart disease as it may increase myocardial oxygen requirements 1, 2
• Monitor for cardiac arrhythmias, particularly in patients with underlying heart disease, hypoxia, or hypercarbia 2
• Be aware that norepinephrine contains sodium metabisulfite, which may cause allergic reactions in susceptible individuals 2

Potential Adverse Effects

• Increased myocardial oxygen consumption 1
• Tissue necrosis if extravasation occurs 1, 2
• Arrhythmias, especially at higher doses 1, 2
• Excessive vasoconstriction leading to end-organ hypoperfusion 1
• Sudden hypotension if discontinued abruptly 2

Special Considerations

• Higher doses of norepinephrine (>10 mcg/minute) are associated with increased mortality in elderly patients 1
• While peripheral administration protocols exist, they require strict adherence to safety parameters and close monitoring 5, 6
• Recent studies suggest that peripheral administration may be safe with proper protocols, potentially avoiding central line placement in 51-52% of patients 6, 7