Inotropic Drugs Flashcards
Inotropic drugs
drugs that increase the force of myocardial contraction
digoxin is a?
cardiac glycoside
Inotropic drugs affect?
the force of muscular contraction
positive inotropic drugs?
increase the force of contraction (digoxin)
negative inotropic drugs?
decrease the force of contraction (beta blockers)
chronotropic drugs effect?
the rate of the heartbeat
positive chronotropic drugs
increase the heart rate
Negative chronotropic drugs
decrease heart rate (digoxin)
Dromotropic drugs affect?
the conduction speed of electrical impulses
negative dromotropic drugs?
slow down the conduction speed (digoxin)
3 S’s of digoxin?
- Strengthens contraction
- Slows hear rate at SA node
- Slows conduction speed at AV node
digoxin can promote
diuresis due to increased kidney perfusion
digoxin has a?
narrow therapeutic index (window)
What can increase digoxin toxicity?
low potassium levels
what are the earlier signs of digoxin toxicity?
anorexia, nausea, vomiting and diarrhea
what are the later signs of digoxin toxicity?
coloured vision (especially seeing yellow), flickering or halos
What is the most serious averse effect of digoxin?
dysrhythmias (including bradycardia)
Which pulse must the nurse check on a person taking digoxin?
apical!
What is the minimum pulse rate in a person taking digoxin?
60 beats per minute
What is the antidote for digoxin toxicity?
digoxin immune Fab therapy
Patients taking digoxin should avoid eating?
high fibre foods because they may decrease the absorption of digoxin
which serum labs should be monitored in a pt taking digoxin?
potassium and renal function
hold dose of digoxin if the HR is ______ in an infant?
less than 90 bpm
slow heart rate in a person taking digoxin could be a sign of?
toxicity
average adult dose of digoxin?
0.125mg/day to 0.5mg/day
indications of phosphodiesterase inhibitors (mirinone)
short term management of heart failure
What are to signs of therapeutic effects?
increased urinary output and decreased crackles in lungs
