Dysrhythmias Flashcards
Rate that the sa node should be between for a normal heart
60-100
What does the sa node do?
It is the pacemaker of the heart and it creates the impulse which then travels to the atria
What is conduction?
what allows for the ATRIA to contract?
Conduction is when the the muscle cells of the atria contract.
The AV node allows for the atria to contract by slowing the impulse down. This allows time for the atria to contract and ventricles to fill
Where does the impulse travel in order for the ventricles to receive the impulse to contract?
The impulse goes from AV node»_space; bundle of his»_space; perkinje fibers in the ventricles
systole
muscle contraction
diastole
muscle relaxation
What does heart depolarization correlate with?
Depolarization corresponds with heart muscles contracting like a wave through the heart
When the heart repolarizes the heart is doing what?
relaxing
What is the impulse doing when the ekg shows a P-wave?
The atria is depolarizing meaning conduction (remember this happens int he atria) is occurring there so there will be corresponding muscle contraction.
What is the impulse doing when the ekg shows a QRS?
The ventricles are just depolarizing and experiencing conduction.
What is going on if there is a T-wave on the ekg?
Ventricles are repolarizing or relaxing
What is the QT interval on an ekg?
Time from ventricles depolarizing to ventricles repolarizing.
What is an ST segment?
When do we common see it?
Early repolarization
Commonly seen elevated with an acute MI
Time for a ONE small box on the ekg
0.04 seconds
Time for ONE large box on the ekg
How many small boxes are in a large box?
0.20 seconds
5 small boxes inside a large box
Time for FIVE large boxes on the ekg
5 large boxes will equal 1 second
How many boxes on an ekg gives you 6 seconds?
30 large boxes
so 150 small boxes
What is positive deflection
Waveforms that move up the paper
First question you ask yourself when you’re assessing the cardiac rhythm on ekg?
Does the rhythm look regular?
- meaning does it look spaced out evenly
Second question you ask yourself when you’re assessing the cardiac rhytm on an ekg?
Are all the pieces there?
- P wave, QRS, T wave?
Third question you can ask yourself when assessing the cardia rhythm on the ekg?
What is the rate?
- add up the amount of boxes in between R intervals (top). then take 1500/n.
Fourth question you can ask yourself when assessing cardiac rhythm on the ekg to double check?
Check and see is the patient presentation lines up with your findings.
Do they have symptoms? Is the issue new or has it always been chronic?
When someone says your st segment is “isoelectric” what do they mean?
At baseline or straight
How big is the Pwave not supposed to exceed?
Should not exceed 1 box in length and 1 box in height
1x1
What is the time length and box length of a normal QRS complex?
0.08-0.12 seconds
2-3 horizontal boxes
What is the time length and box length of a normal PR interval?
How is this measured?
0.12-.20 seconds
3-5 horizontal boxes
Beginning of the P wave to the onset of the QRs. (initial wave can sometimes be an R isnead of the Q)
T/F
Sa node stimulates the heart for a rate of 40-60 bpm and the impulse travels to the ventricles
False.
Sa node heart rate is the higher one of 60-100.
The impulse of the sa node travels to the atria.