Vasoactive Medications used in ICU
Most of the time vasoactive medications are sued to increase blood pressure (Vasconstrictors) and cardiac output (Inotropes). They include Dopamine, Norepinephrine, Epinephrine, and Phenylephrine.
Dopamine: low doses (1-3 ug/kg/minute) act only on dopamine receptors in kidney are intestine to increase blood flow. Medium doses (3-10 ug/kg/minute) act on Beta receptors (beta agonist) to increase cardiac contractility and cardiac output. Higher doses (10 ug/kg/minute and above) act on alpha receptors (alpha agonist) to act as a vasoconstrictor.
Dobutamine: acts on both B1 and B2 receptors. Increases cardiac output and also causes vasodilation. Good for cardiogenic shock.
Norepinephrine: alpha agonist (causes vasoconstriction) and some beta activity (increases heart contractility)
Epinephrine: also an alpha agonist and some beta agonist activity. Vasoconstriction and increased heart output/contractility. Epinephrine causes more tachycardia than norepinephine.
Nitroprusside: arterial vasodilation. Can cause cyanide poisoning and acidosis
Nitroglycerin: venodilator and coronary artery dilator. Good for decreasing venous preload (decreases diastolic wall tension for better heart contraction) and allows for increased blood flow to the heart.