What is the drip rate for a 70 kg patient on Levophed (Norepinephrine) at 0.1 micrograms/kg/min?

From the Guidelines

To calculate the drip rate for a 70 kg patient on levophed (norepinephrine) at 0.1 mcg/kg/min, you would need to set the infusion pump to 7 mcg/min. This is determined by multiplying the patient's weight (70 kg) by the prescribed dose (0.1 mcg/kg/min) [ 1 ]. Levophed is typically prepared in a standard concentration of 4 mg in 250 mL of D5W or NS, yielding 16 mcg/mL. With this concentration, the infusion rate would be 0.44 mL/min or 26.3 mL/hour. It's essential to use an infusion pump for accurate delivery of this vasopressor. Monitor the patient's blood pressure frequently after initiating therapy, as norepinephrine causes peripheral vasoconstriction to increase blood pressure in hypotensive states [ 1 ]. Some key points to consider when using norepinephrine include:

• Titrate the dose based on the patient's hemodynamic response, aiming for a target mean arterial pressure (MAP) of at least 65 mmHg or as specified in the patient's care plan [ 1 ].
• Ensure the IV site is patent and monitored regularly, as extravasation of norepinephrine can cause severe tissue damage.
• Consider adding either vasopressin (up to 0.03 U/min) or epinephrine to norepinephrine with the intent of raising mean arterial pressure to target, or adding vasopressin (up to 0.03 U/min) to decrease norepinephrine dosage [ 1 ]. The use of norepinephrine as a first-choice vasopressor is a strong recommendation with moderate quality of evidence [ 1 ].

From the FDA Drug Label

Average Dosage: Add the content of the vial (4 mg/4 mL) of LEVOPHED to 1,000 mL of a 5 percent dextrose containing solution. Each mL of this dilution contains 4 mcg of the base of LEVOPHED The average maintenance dose ranges from 0.5 mL to 1 mL per minute (from 2 mcg to 4 mcg of base).

To calculate the drip rate for a 70 kg patient on Levophed (Norepinephrine) at 0.1 micrograms/kg/min:

• Dose: 0.1 micrograms/kg/min * 70 kg = 7 micrograms/min
• Concentration: 4 micrograms/mL
• Drip rate: 7 micrograms/min / 4 micrograms/mL = 1.75 mL/min

The drip rate for a 70 kg patient on Levophed (Norepinephrine) at 0.1 micrograms/kg/min is 1.75 mL/min 2

From the Research

Calculating Drip Rate for Levophed (Norepinephrine)

To calculate the drip rate for a 70 kg patient on Levophed (Norepinephrine) at 0.1 micrograms/kg/min, we need to follow these steps:

• First, calculate the total dose of norepinephrine required per minute: 0.1 micrograms/kg/min * 70 kg = 7 micrograms/min
• The standard concentration of norepinephrine is 4 mg in 250 mL (16 mcg/mL or 0.016 mg/mL) of solution, but this can vary. Assuming this standard concentration, the volume of solution required per minute can be calculated as follows: 7 micrograms/min / 16 mcg/mL = 0.4375 mL/min
• However, the provided studies do not directly address the calculation of drip rates for norepinephrine administration. They discuss various aspects of norepinephrine use in critically ill patients, such as dosing requirements in obese and nonobese patients 3, the association between norepinephrine dosage and lactate clearance in septic shock patients 4, and the predictive role of vasopressors in patients with shock 5.

Key Findings Related to Norepinephrine Administration

• A study published in 2021 found that norepinephrine dosage is associated with lactate clearance after resuscitation in patients with septic shock 4.
• Another study from 2016 compared norepinephrine dosing requirements in obese and nonobese patients with septic shock, finding that obese patients required lower weight-based doses 3.
• The study from 2013 examined the predictive role of vasopressors in patients with shock and found that norepinephrine administration was an independent predictor of ICU death 5.

Considerations for Drip Rate Calculation

• The calculation of the drip rate depends on the specific concentration of the norepinephrine solution being used.
• It's crucial to consult the specific guidelines or protocols in place at the healthcare facility for the administration of norepinephrine, as these can vary.
• The provided studies offer insights into the clinical use and effects of norepinephrine but do not provide a direct formula for calculating drip rates based on patient weight and desired dosage 6, 5, 4, 7, 3.