Raivas injections is a concentrated, potent drug which must be diluted in dextrose-containing solutions prior to infusion. An infusion of norepinephrine should be given into a large vein (see Precautions).
Restoration of Blood Pressure in Acute Hypotensive States: Blood volume depletion should always be corrected as soon as possible before any vasopressor is administered. When used as an emergency action, intra-aortic pressure must be maintained to prevent cerebral or coronary artery ischaemia, norepinephrine may be given before and concurrently with blood volume replacement.
Diluent: Norepinephrine should be diluted in 5% dextrose injection or 5% dextrose and sodium chloride injections. This dextrose-containing solution significantly provides protection against loss of potency due to oxidation. The administration of norepinephrine in sodium saline solution alone is not recommended. Whole blood or plasma, if indicated to raise the blood volume should be administered separately (eg, by use of a Y-tube and individual container when given simultaneously).
Average Dosage: Add 4 mL (4 mg) of norepinephrine into 1000 mL of 5% dextrose-containing solution. Each mL of this dilution contains norepinephrine base 4 mcg. Administer the solution by IV infusion. Insert the plastic IV catheter through a suitable bore needle well advanced centrally into the vein then fixed with adhesive tape. If possible, avoid a tie-in catheter technique, as this promotes stasis. IV drip chamber or other suitable metering device is required to accurately measure the rate of flow in drops/min. After observing the response to an initial dose of 2-3 mL (from 8-12 mcg of base)/min, adjust the rate of flow to establish and to maintain a low normal blood pressure (usually 80-100 mm Hg of systolic blood pressure) sufficient to maintain the circulation to vital organs. In patients with a history of hypertension, it is recommended to increase blood pressure not higher than 40 mm Hg below the preexisting systolic pressure. The average maintenance dose is 0.5-1 mL/min (2-4 mcg of base form).
High Dosage: Each person needs variation of dose to establish and maintain an adequate blood pressure. In all cases, dosage of norepinephrine should be titrated according to patient response. Occasionally, much larger or even enormous daily dose (as high as 68 mg base or 17 ampoules) may be necessary if patients remain hypotensive, but any presence of occult blood, volume depletion should be suspected and corrected when present. Monitoring of central venous pressure is usually helpful in detecting and treating this condition.
Fluid Intake: The degree of dilution depends on the requirement of clinical fluid volume. If large volume of fluid (dextrose) is needed at a flow rate that would involve an excessive dose of the pressor agent per unit of time, a solution which is more diluted than 4 mcg/mL should be used. On the other hand, when large volumes of fluid are clinically undesirable, a concentration of >4 mcg/mL may be necessary.
Duration of Therapy: The infusion should be continued until adequate blood pressure and tissue perfusion are maintained without therapy. Infusions of norepinephrine should be gradually reduced, avoiding the abrupt withdrawal. In some of the reported cases of vascular collapse due to acute myocardial infarction, treatment was required for up to 6 days.
Adjunctive Treatment in Cardiac Arrest: Infusions of norepinephrine are usually administered IV during cardiac resuscitation to restore and maintain an adequate blood pressure after an effective heartbeat and ventilation have been established by other means. [Norepinephrine's powerful β-adrenergic-stimulating action is also thought to increase the strength and effectiveness of systolic contractions].
Average Dosage: To maintain systemic blood pressure during the management of cardiac arrest, norepinephrine is used in the same manner as described previously under Restoration of Blood Pressure in Acute Hypotensive States.
Parenteral drug products should be visually observed for any particulate matter and discolouration prior to use, whenever solution and container permit.
Do not use the solution if its colour is pinkish or darker than slightly yellow or if it contains a precipitate.
Avoid contact with iron salts, alkalis or oxidising agents.