Inotropes

Question 1

MOA of dobutamine

Answer 1

Stimulates beta 1 and beta2 receptors

Both ionotropic and chronotropic effects. Inotropic effects on the myocardium through binding and activating the beta-1 receptors selectively.

Question 2

MOA of dopamine

Answer 2

Vasodilator at low dose
Vasoconstrictor at high dose

Mimics agonist actions of alpha and/or beta adrenoreceptors

Question 3

Milrinone MOA

Answer 3

Selective inhibitor of peak cAMP phosphodiestase
High cAMP level rises intracellular ionised Ca levels

Question 4

Digoxin MOA

Answer 4

Inhibits Na/K ATPase

Question 5

Adrenaline MOA

Answer 5

Endogenous catecholamine
Beta 1 > Alpha
Inotropic, dromotrophy, chronotropy

Question 6

Noradrenaline MOA

Answer 6

Endogenous catecholamine
Vasoconstriction, inotrophy
Alpha 1 > Beta 1

Question 7

Levosimendan MOA

Answer 7

Inodilator
Increases sensitivity of heart to calcium (increases calcium sensitivity of myocytes by binding to cardiac troponin C)
Opens ATP-sensitive K channels in smooth muscles

Used in low CO state

Question 8

MOA of midodrine

Answer 8

Midodrine hydrochloride, an α1-agonist, increases effective circulating blood volume and renal perfusion by increasing systemic and splanchnic blood pressure.

Question 9

MOA of dexmedotomidine

Answer 9

Dexmedetomidine is an alpha 2 adrenoreceptor agonist having sedative, anxiolytic, hypnotic, analgesic, and sympatholytic properties.

Question 10

MOA of phenylephrine and metarminol

Answer 10

Acts on alpha 1
Vasoconstriction and inotrophy

Question 11

MOA of isoprenaline

Answer 11

Acts on beta receptors, beta 1 > beta 2