Cardiac Glycosides Flashcards
What are cardiac glycosides indicated for?
- CHF, atrial fibrillation, atrial flutter, PAT
What is one of the main interactions of cardiac glycosides?
- with ANTIBIOTICS YO
What is the MOA of digoxin?
- inhibition of Na, K-ATPase pumps
What are the effects of cardiac glycosides on the autonomic NS
- parasymp: increased release of acetylcholine
- symp: increased efferent sympathetic discharge
What is the toxic dose of digoxin
1 mg in a child, 3 mg in an adult
What is considered to be an overdose of of digoxin?
- OD > 10 mg of healthy subjects
What is considered a toxic level of dig?
- > 2 ng/mL
What DI’s are associated with digoxin?
- amiodarone (inhibits renal tubular secretion)
- antibiotics (decrease population of colonic bacteria)
- quinidine
- verapamil
What disease states are a risk factor for digoxin toxicity
- renal failure
- MI
- electrolyte imbalances
- mortality is 3-25% higher in elderly
What are the s/s of acute overdose?
- vomiting
- hyperkalemia
- sinus bradycardia
- sinoatrial arrest
- second or third degree AV block
- ventricular tachycardia/fibrillation
What are the s/s associated with chronic intoxication?
- visual disturbances (dychromatopsia)
- weakness
- sinus bradycardia
- a. fib
- ventricular arrhythmias
- accelerated junctional tachycardia
- paroxymal atrial tachycardia
- hypokalemia and hypomagnesemia (from use of diuretics)
What is the management of glycoside intoxicated patients?
emergency and supportive care measures
- protect airways, assist ventilation
- tx hyperkalemia
- treat bradycardia or heart block
- treat ventricular tachyarrhythmia
- decontamination (GI emptying, activated charcoal)
- enhanced elimination (MDAC)
- antidotes (DIG- antibodies)
- monitoring dig levels
When is Gastric emptying and activated charcoal appropriate for patients?
- in a recent overdose, when the drug is still in the stomach
Why is MDAC a less efficient way of managing a patient?
- drug is not in plasma anymore due to large Vd- this kind of intervention can still be used to lower plasma levels even just a little bit but is not as efficient of an eliminator
What is the benefit of using digibodies?
-the affinity that these antibodies have for dig is much higher than the affinity that dig has for the receptors- you will have a high plasma level, but it is not toxic anymore after using the digoxin antibodies
