20. Inotropic Drugs-Limitations in Heart Failure Flashcards
Why does hypocalcemia cause dig tox?
dig enhances Ca++ absorption by myocytes (that’s the point, but don’t overdo it)
Digoxin can also bind in the ____ and ____ of the heart to slow the HR and treat A-fib.
SA node; AV node
What is dobutamine?
inotropic drug
What are the s/s of dig tox?
- GI: upset/pain/vomiting**** 2. neuro: weakness, confusion 3. hyperkalemia 4. cardiac: bradycardia, heart block, arrhythmias 5. visual: sensitivity to light, yellow halos, blurred vision
With increased plasma NE, there is an increased risk of _____ in HF pts.
death
_____ increases PNS activity by activating baroreceptors in the carotids and the AA.
Digoxin
What is milrinone?
an ionotropic drug
_____ are like a protective shield for the heart in overproduction of NE.
Beta-blockers
What is the half life of digoxin?
38 hours (7-10 days to steady state)
The diuretics end in -____.
ide
How does digoxin increase parasympathetic activity?
by increasing baroreceptor sensitivity in the carotids and the AA
How does milrinone work?
it inhibits phosphodiesterase (PDE) to increase force of contraction and also causes vasodilation
If your pt has a life-threatening dig tox or OD, give _____.
digoxine immune Ab
_____ can also bind in the SA and AV node of the heart to slow the HR and treat A-fib.
Digoxin
What is the problem with the inotropes?
they can be pro-arrhythmic
____ is an inotrope that blocks the Na+/Ca++ ATPase.
Digoxin
Beta-blockers have been shown to reduce morbidity and mortality and is recommended for all ______ pts unless contraindicated.
HFrEF
What is dopamine?
a precursor of NE; benefits = RIP (renal, inotropic, and pressor effects depending on dose)
You would not give _____ to someone already taking a beta-blocker.
dobutamine
Beta-blockers improve the overall ____ of the heart and decrease mortality over time.
ejection fraction
Digoxin is an inotrope that blocks the Na+/Ca++ ATPase, causing ____ to accumulate on the ____ side.
Na+; intracellular
Why does hypomagnesemia cause dig tox?
can sensitize the heart to dig-induced arrhythmias
Digoxin reduces _____ but does not impact mortality.
hospitalization
Which has the shorter half life: milrinone or dobutamine?
dobutamine
