Inotropes and Vasopressors
The understanding of how the heart works is fundamental for our intensivist to provide cardiovascular support.
Inotropes are pharmalogical agents that increase force of ventricular contraction, usually ß-effect
Vasopressor constricts blood vessels, α-effect.
Chronotrope increases heart rate, ß-effect.
- both α and ß-effect.
- inotope, vasopressor and chronotrope
- ß2 effect at low doses causing vasodilatation in skeletal muscle thus lowering SVR.
- α-vasoconstrictor effect at higher doses will increase SVR and myocardial oxygen demands, with adverse effect on cardiac output.
- α-effect, vasopressor
- indicate din septic shock when hypotension is due because of massive peripheral vasodilatation which will persist despite fluid/volume resuscitation.
- ß1 and ß2 effect.
- Inotrope, vasodilator
- ß1 effect increases heart rate and force of contraction
- ß2 causes mild vasodilatation
- This is the first choice of inotropes in cardiogenic shock due to left ventricular dysfunction.
- Dobutamine and low dose dopamine in conjunction used in cardiogenic shock to increase blood pressure by increasing cardiac contractility and urinary output (UO). This will increase renal perfusion.