Average Dosage: Add 2 mL of the 1:1000 solution of Levophed SF to 500 mL, (or Levophed SF 4 mL to 1 L) of glucose 5% solution. Each 1 mL of this dilution contains 4 mcg of noradrenaline (equivalent to 8 mcg of the acid tartrate). Give this dilution IV via a catheter well advanced centrally into the vein and securely fixed, if possible, avoiding a catheter tie-in technique as it promotes stasis. A drip bulb is necessary to permit an accurate estimation of the rate of flow in drops per minute. After observing the response to an initial dose of 2-3 mL/min (8-12 mcg of base), adjust the rate of flow to establish and maintain a low normal blood pressure (usually 80-100 mm Hg systolic) sufficient to maintain the circulation to vital organs. In previously hypertensive patients, it is recommended that the blood pressure should be raised no higher than 40 mm Hg below the preexisting systolic pressure. The average maintenance dose ranges from 0.5-1 mL/min (2-4 mcg of base). Occasionally, much larger daily doses (as high as 68 mg base or 34 ampules) may be necessary if the patient remains hypotensive, but occult blood volume depletion should always be suspected and corrected when present. Dilution can be varied depending on the clinical fluid volume requirement.
Duration of Therapy: The infusion should be continued until adequate blood pressure and tissue perfusion are maintained without therapy. The infusion rate should then be reduced gradually, avoiding abrupt withdrawal. In some of the reported cases of vascular collapse due to acute myocardial infarction, treatment was required for up to 6 days.