EKG fuNn Flashcards
Where would you place V1 and V2 on a patient?
On either side of the sternum
- at the 4th intercostal space
Where is V4 on a patient?
The apex of the heart
Where are V5 and V6 on a patient?
Horizontally laterally to the left of V4
Are the limb leads bipolar or unipolar?
Bipolar - calculate the electric potential between two different leads
What is lead I between?
What is lead II between?
What is lead III between?
- Right arm and Left arm
- Right arm and left leg
- left leg and left arm
Are the aVR, aVL, and aVF leads bipolar or unipolar?
They are unipolar
-record the electric potential between the speciic electrode and zero potential
Where is avR?
Where is aVL?
where is aVF?
aVR - right arm
aVL - left arm
aVF - left leg
**note the right leg has an electrode but this is the earth electrode
Are V1-6 bipolar or unipolar?
What is another name for these leads?
What is the polarity that they record?
- Unipolar
- V1-6 are precordial leads
- front to back
What is the patient’s position when performing an ekg?
supine, at rest
What polarity do the limb leads record?
front to back and left to right
How would you graph the planes of view for an ekg?
- aVL
- aVR
- III
- II
(-90)
(2) I
I (1)
(-180) ---------I----------- (0)
I
(3) I (4)
(+90)
- aVL is -30 degrees
- aVR is -150 degrees
- III is +120 degrees
- II is +60 degrees
-it goes clock wise but starts at 3’oclock
Which leads give a view from the inferior?
II, III, aVF
Which leads give a view from the anterior?
I, aVL, V1-3
Which leads give a view septally?
V3, V4
Which leads give a view of the heart laterally?
V4-6
What are the steps of depolarization of the heart ? (5)
- SA node
- AV node - delayed
- Bundle of HIS
- Right and Left bundle branches
- Purkinje fibers - ventricular walls
If electrical activity is directed towards a lead, how will that be shown in an EKG?
towards - deflection upwards
away - deflection downwards
Where is the PR interval?
What does this represent
from the beginning of the P to the beginning of Q (ya weird I know….)
-initial depolarization of the ventricle
Where is the QRS interval?
What does this represent?
from beginning of Q to end of S
-depolarization of the ventricles
Where is the ST segment?
What does this represent?
end of S to beginning of T
-period when ventricles are depolarized
Where is the QT interval?
What does this represent?
beginning of Q to end of T
-entire period of depolarization and repolarization of the ventricles
After a P wave, an upwards reflection is a what?
R wave
After a P wave, a downwards reflection is a what?
Q wave
What are some ways to calculate rate?
- count the large boxes and divide this by 300
- 5 = 60 BPM, 3 = 100 BPM
- 1500 divided by the number of small boxes
What does the P wave represent?
atrial depolarization (does not include repolarization - buried in QRS)
What does the T wave represent?
Ventricular repolarization
What is the axis?
Net direction of electrical activity during depolarization
How would you calculate the axis?
- Find QRS in lead I and aVF ( there are at 0 and 90)
- subtract S wave height from R wave height
-Plot: I - net positives to the right, net negs left
aVF - positive down & negative upwards
What wave is especially important to check for sinus rhythm?
P waves - check for them before every QRS
What would you diagnose a patient with if they have baseline noisiness, and no P waves?
atrial fibrillation
What can the axis be altered by ?
L or R ventricular hypertrophy
-bundle branch blocks
