ECG - Rate and rhythm Flashcards
What is the standard output on an ECG?
1 - 5mm/sec
2 - 15mm/sec
3 - 25mm/sec
4 - 40mm/sec
3 - 25mm/sec
- has 250 small squares
= 0.04 x 250 = 10 secs - has 50 large squares
= 0.2 x 50 = 10 secs
Typically there are 5 small squares per 1 large square. How long is 1 small square on a normal ECG?
1 - 0.04 secs
2 - 0.1 secs
3 - 0.2 secs
4 - 0.5 secs
1 - 0.04 secs
Typically there are 5 small squares per 1 large square. How long is 1 large square on a normal ECG?
1 - 0.04 secs
2 - 0.1 secs
3 - 0.2 secs
4 - 0.5 secs
3 - 0.2 secs
- 5 small squares =
5 x 0.04 = 0.2 secs
If we record a rhythm strip for 1 minute, how many small squares will there be in total?
1 - 1200
2 - 1500
3 - 2000
4 - 2500
2 - 1500
- 250 small squares = 10 seconds (0.04 x 250)
- 250 x 6 = 1500 small squares (0.04 x 1500)
If we record a rhythm strip for 1 minute, how many large squares will there be in total?
1 - 100
2 - 200
3 - 300
4 - 400
3 - 300
- 50 large squares = 10 seconds (0.2 x 50)
- 50 x 6 = 300 small squares
(0.2 x 300)
We can calculate the heart rate by using the large square method. What is this?
1 - number of large squares between R-R intervals
2 - number of small squares between R-R intervals
3 - number of R waves (on strip) x 6
4 - number of p waves x 6
1 - number of large squares between R-R intervals
- 300 large squares/min
- i.e. 5 large squares between R-R intervals =
300/5 = 60bpm
We can calculate the heart rate by using the small square method. What is this?
1 - number of large squares between R-R intervals
2 - number of small squares between R-R intervals
3 - number of R waves (on strip) x 6
4 - number of p waves x 6
2 - number of small squares between R-R intervals
- 1500 small squares/min
- i.e. 15 small squares between R-R intervals =
1500/15 = 100bpm
We can calculate the heart rate by using the R wave method. What is this?
1 - number of large squares between R-R intervals
2 - number of small squares between R-R intervals
3 - number of R waves (on strip) x 6
4 - number of p waves x 6
3 - number of R waves (on strip) x 6
- 9 R waves = 9 x 6 = 54bpm
To determine the rhythm of an ECG we need to look at the rhythm strip. Which lead is this best seen in?
1 - lead I
2 - lead AVL
3 - lead II
4 - lead AVR
3 - lead II
- best because it follows similar path as the electrical current
What is the 1st step of the 7 step ECG rhythm analysis of an ECG?
1 - p wave
2 - QRS pattern
3 - rate
4 - QRS morphology
3 - rate
- using R wave method calculate HR
What is the 2nd step of the 7 step ECG rhythm analysis of an ECG?
1 - p wave
2 - QRS pattern
3 - rate
4 - QRS morphology
2 - QRS pattern
- regular or irregular
- is it regularly irregular
What is the 3rd step of the 7 step ECG rhythm analysis of an ECG?
1 - p wave
2 - QRS pattern
3 - rate
4 - QRS morphology
4 - QRS morphology
- narrow = sinus, atrial or junctional origin
- wide = ventricular origin, or supraventricular with aberrant conduction.
What is the 4th step of the 7 step ECG rhythm analysis of an ECG?
1 - p wave
2 - QRS pattern
3 - rate
4 - QRS morphology
1 - p wave
- Absent = sinus arrest or atrial fibrillation
- Present = morphology and PR interval may suggest sinus, atrial, junctional or even retrograde from the ventricles.
What is the 5th step of the 7 step ECG rhythm analysis of an ECG?
1 - p and QRS relationship
2 - QRS pattern
3 - rate
4 - QRS morphology
1 - p and QRS relationship
- AV association
- AV dissassociation
What is the 6th step of the 7 step ECG rhythm analysis of an ECG?
1 - p and QRS relationship
2 - QRS pattern
3 - rate
4 - onset and termination
4 - onset and termination
- Abrupt = re-entrant process
- Gradual = increased automaticity
What is the 6th step of the 7 step ECG rhythm analysis of an ECG?
1 - p and QRS relationship
2 - QRS pattern
3 - response to vagal manoeuvres
4 - onset and termination
3 - response to vagal manoeuvres
- Sinus tachycardia or ectopic atrial tachydysrhythmia = gradual slowing during the vagal manoeuvre, but resumes on cessation.
AVNRT or AVRT = abrupt termination or no response.
Atrial fibrillation and atrial flutter = gradual slowing during the manoeuvre.
VT = no response.
AVNRT = Atrioventricular nodal reentry tachycardia
AVRT = Atrioventricular reciprocating tachycardia
