cardiotonic and inotropic drugs

Question 1

Drugs used to increase the efficiency and improve contraction of heart muscle

Answer 1

cardiotonics

Question 2

Happens when the heart is unable to pump blood in sufficient amounts from the ventricles. Called pump failure.

Answer 2

heart failure

Question 3

most commonly used cardiotonic

Answer 3

Digoxin (Lanoxin)

Question 4

actions of cardiotonics

Answer 4

• Increase cardiac output through positive inotropic activity
• Increase force of contraction of heart
• Increased blood leaving L ventricle
• Increased blood supply to tissues/organs
• decrease in pulse

Question 5

Cardiotonic uses

Answer 5

• heart failure

- atrial arrhythmias

Question 6

adverse reactions of cardiotonics

Answer 6

• Narrow range of safety between full therapeutic effects and toxic effects
• Digitalis Toxicity can occur with any cardiotonic
• Because of rapid onset and short duration, digoxin is most often prescribed

Question 7

Signs of digitalis toxicity

Answer 7

• Anorexia, Nausea, Vomiting, Diarrhea
• Drowsiness, visual disturbance, halo effect around objects (green, yellow, and purple), flickering lights
• Headache, convulsions, confusion
• Changes in pulse rate or rhythm; EKG changes, bradycardia, tachycardia, bigeminy, trigeminy

Question 8

caution with patients taking:

Answer 8

diuretics

-loss of K+ with diuretics= hypokalemia (heart more sensitive to digitalis)

Question 9

• Series of doses given until the drug begins to exert a full therapeutic effect
• Then placed on maintenance dose schedule
• Monitor VS q2-4 hr during digitalization
• Periodic labs or EKG’s

Answer 9

digitalization (loading dose)

Question 10

lab level for digoxin therapeutic level=

Answer 10

0.5 - 2 ng/mL

Question 11

lab level for digoxin

toxic level=

Answer 11

more than 2 ng/mL