Dopamine (Intropin)

Question 1

Pharm. and Action

Answer 1

Chemical precursor of epinephrine which occurs naturally in man; Has both alpha and beta receptor stimulating actions depending upon the dose; 1-2 mcg/kg dilates renal and mesenteric vessels; 2-10 mcg/kg beta effects on heart which usually increase cardiac output without increasing heart rate or blood pressure; 10-20 mcg/kg alpha peripheral effects cause vasoconstriction and increase blood pressure; 20-40 mcg/kg alpha effects reverse dilation of renal and mesenteric vessels resulting in decreased flow

Question 2

Indications

Answer 2

Primary indication is cardiogenic shock; useful in other forms of shock except hypovalemic

Question 3

Contraindications

Answer 3

Infusion should be decreased or stopped if tacharrhythmias or HTN occur; hypovalemic shock

Question 4

Administration

Answer 4

Adult infusion dose- premix IV bag with 400 mg of dopamine in 250 ml NS; Infusion rate should start between 2-5 mcg/kg/min, gradually increasing to 10-20 mcg/kg/min until desired effect is achieved. Microdrip chamber only

Question 5

Side effects and Special Notes

Answer 5

Ectopic beats, N/V, angina, VT, VF, HTN, headache, ischemia, AMI; Can precipitate hypertensive crisis in susceptible individuals especially those on MAO inhibitors; Best administered by an infusion pump to accurately regulate rate; Rule out hypovalemic shock and treat with appropriate fluis before administration of dopamine; Should not be added to sodium bicarbonate or other alkaline solution since dopamine will be deactivated in alkaline solutions

Question 6

Class

Answer 6

C