Clin Lab - EKG rate Flashcards
What does heart function tell us?
- Electrical conduction system
- Infarction
What does heart structure tell us?
- Hypertrophy
- Axis
Does the EKG tell us if the heart beats?
NO
How do we assess if a heart is actually beating?
pulse
What is the dominant pacemaker of the heart?
SA node
Where is the SA node located?
posterior (top) right atrium
How does the parasympathetic and sympathetic nervous system affect the SA node?
controls how many Na+ channels are opened or closed
When do you not use the 300-150-100 count? what do we uses?
- bradycardic rates
- very irregular rates
- uses 6 sec method for these rates
Any rhythm originating from the SA node is called a _____
sinus rhythm
- regular, consistent P wave
SA node: normal rate
60 - 100 bpm
If the SA node isn’t working, name the backup system in place to pace heart.
- Atrial foci (Ectopic atrial)
- Atrioventricular (AV) node junction (Junctional)
- Ventricular Foci (Idioventricular)
Atrial foci (Ectopic atrial) Rate
60 - 80 bpm
AV node junctional Rate
- typical junctional rate 40 - 60 bpm
- accelerated junctional rate 60 - 80 bpm
3 ways to calculate rate
- 300-150-100
- 6 sec count
- 10 sec
Ventricular foci (idioventricular) Rate
- typical 20 - 40 bpm
- accelerated idioventricular rate 40 - 60 bpm
Describe the 300-150-100 count & what part of the EKG is used?
300-150-100-75-60-50
- use 10 sec rhythm strip
Describe how to used the 300-150-100 count
- find an R wave that fall on the big box block line
- start counting each big box line after that
- If the second wave fall b/t two big box lines; calculate what little boxes would equal
Describe 6 sec count.
Count the # of R waves in a 6 sec interval & multiply by 10
Describe 10 sec count.
If it is a 10 sec EKG, count total number of QRS complexes & multiply by 6
How can you determine if a rhythm is irregular?
measure the R-R interval
What must be present on the EKG to use 6 sec count?
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