Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
13 Cards in this Set
- Front
- Back
Dysrhythmias are categorized by ___________ and _______________________.
|
location
type of rhythm abnormality |
|
What is the pacemaker of the heart?
|
SA - sinoatrial node
|
|
What is automaticity?
|
the ability to spontaneously generate an electrical impulse known as an action potential, without instruction from the nervous system.
|
|
Normal Sinus Rhythm
|
SA node generates a new action potential (approx 75 times every minute under resting condition)
|
|
A cell having a negative membrane potential is said to be _______________.
|
polarized
|
|
In resting cells, sodium and calcium are found in higher concentrations (inside or outside) the cell.
|
outside
|
|
What is the pharmacological strategy used to terminate or prevent dysrhythmias?
|
Block potassium, sodium, and calcium ion channels
|
|
What is the action of sodium channel blockers?
|
slows the rate of impulse conduction through the heart.
|
|
What is the action of beta-adrenergic blockers?
|
reduce automaticity as well as slow conduction velocity in the heart
|
|
What is the action of potassium channel blockers
|
prolong the refractory period of the heart
|
|
What is the action of calcium channel blockers?
|
slow conduction velocity
|
|
Calcium channel blockers are only effective against _____________ dysrhythmias.
|
supraventricular
|
|
Drugs that do not act by blocking ion channels include ___________, __________, and __________.
|
adenosine (Adenocard, Adenoscan)
digoxin (Lanoxin) ibutilide fumarate (Corvert) |