Recommended Starting Infusion Rate for Levophed (Norepinephrine) in Adults with Hypotension
The recommended starting infusion rate for Levophed (norepinephrine) in adults with hypotension is 2-3 mL/minute (8-12 mcg/minute) of a solution containing 4 mg of norepinephrine in 1,000 mL of 5% dextrose solution. 1
Preparation and Administration
- Levophed should be diluted in 5% dextrose solution or 5% dextrose and sodium chloride solution to protect against potency loss due to oxidation 1
- Standard dilution: Add 4 mg (4 mL) of norepinephrine to 1,000 mL of dextrose-containing solution, resulting in a concentration of 4 mcg/mL 1
- Administration should be through a central venous line whenever possible to prevent tissue necrosis from extravasation 2
- A plastic intravenous catheter should be inserted through a suitable bore needle well advanced centrally into the vein and securely fixed with adhesive tape 1
- An IV drip chamber or other suitable metering device is essential for accurate flow rate measurement 1
Initial Dosing and Titration
- After observing the response to the initial dose of 2-3 mL/minute (8-12 mcg/minute), adjust the rate to establish and maintain a low normal blood pressure 1
- The average maintenance dose ranges from 0.5-1 mL/minute (2-4 mcg/minute) 1
- Titrate to achieve a target mean arterial pressure (MAP) of 65-100 mmHg, sufficient to maintain vital organ perfusion 2
- In previously hypertensive patients, the blood pressure should be raised no higher than 40 mmHg below the preexisting systolic pressure 1
Monitoring and Safety Considerations
- Continuous hemodynamic monitoring is essential during administration 2
- Monitor for signs of extravasation; if it occurs, infiltrate 5-10 mg of phentolamine diluted in 10-15 mL of saline into the site to prevent tissue necrosis 2
- Blood volume depletion should always be corrected before or concurrently with norepinephrine administration, as it is relatively contraindicated in hypovolemic patients 2
- Use cautiously in patients with ischemic heart disease as it may increase myocardial oxygen requirements 2
Special Considerations
- Great individual variation occurs in the dose required to maintain adequate blood pressure; in all cases, dosage should be titrated according to patient response 1
- Higher doses of norepinephrine (>10 mcg/minute) are associated with increased mortality and should be avoided if possible 2
- For profound hypotension, early administration of norepinephrine (within the first hour) may be beneficial for shock control 3, 4
- In obese patients, non-weight-based dosing may be more appropriate as they typically require lower weight-based doses but similar total doses compared to non-obese patients 5
Weaning Protocol
- Infusions should be continued until adequate blood pressure and tissue perfusion are maintained without therapy 1
- Decrease the norepinephrine dose by 25% of the current dose every 30 minutes as tolerated 2
- Avoid abrupt withdrawal of the infusion 1
Common Pitfalls and Caveats
- Administration in saline solution alone is not recommended 1
- Avoid contact with iron salts, alkalis, or oxidizing agents 1
- Risk factors for extravasation include hypertension, edema, long-term infusion (>24 hours), infusion concentration >60 mg/L, and infusion speed >0.3 μg/kg/min 6
- If large volumes of fluid are clinically undesirable, a concentration greater than 4 mcg/mL may be necessary 1
- When norepinephrine doses reach 0.25-0.50 μg/kg/min, consider adding arginine vasopressin as an adjunct therapy 7