Usage and Dosage: Start with intravenous infusion at a rate of 16-24 μg/min, and then assess the patient response and adjust the dose accordingly to maintain the desired hemodynamic effect. Monitor blood pressure every 2 minutes until the desired hemodynamic effect is achieved, and then monitor the pressure every 5 minutes during the infusion period. The average maintenance dose is 4-8 μg per minute. Drug discontinuation: For stopping the infusion, gradually reduce the flow rate. Abrupt drug discontinuation shall be avoided. Drug incompatibility: This product shall avoid contact with iron salts, alkalis and oxidants. If whole blood or plasma is needed to increase blood volume, this product shall be administered separately from whole blood or plasma infusion. Commonly used dose for children: Start with intravenous drip at a rate of 0.02-0.1 μg/kg per minute according to the body weight and then adjust the rate as needed.