help in EKG for school needed.?

Question

for someone who teaches EKG. What is the answer for the following question.
" Which of the following electrocardiograph leads records electrical activity from the midpoint between the left arm and left leg to the right arm?"
Is the answer lead III or aVR? My teacher said it's lead III. But my textbook said it's aVR lead. My teacher mark it wrong on the test and wouldn't give me the point back. I'm really upset. Why is the information in textbook different than what is on the test?

Answer 1

You are correct, the lead is aVR

Lead I, II, III form a triangle across your chest:
lead I: right shoulder to left shoulder
lead II: right shoulder to left foot
lead III: left shoulder to left foot

aVR, aVL, aVF form a "Y" and start from above the belly button (slightly to the left):
aVR: belly button to Right shoulder
aVL: belly button to Left shoulder
aVF: belly button to the feet

The other leads (chest leads) V1,2,3,4,5,6 wrap around the heart
V1 & V2 = septal leads
V3 & V4 = anterior leads
V5 & V6 = lateral leads

Good luck with your instructor... :(

Answer 2

Your teacher is right. If you would read on, I will explain why.

Since both leads are "looking" from the same vantage point, we need to decide why their readings show different measurements.

1. The augmented leads (aVR, aVL, aVF) are designed to increase the amplitude of the deflections over those recorded by the standard limb leads. The augmented leads are UNIPOLAR in nature and record electrical POTENTIAL from both the right and left arms and the left leg.

2. The standard limb leads (I, II, III) record frontal plane activity. These leads are BIPOLAR leads. Each lead records the DIFFERENCE of electrical potential between two selected electrode sites.

We have to understand that aVR is showing that the path of potential is going toward the left leg. Since that pathway is directly opposite from the right arm, then aVR is really showing that the electrical pathway is traveling away from the right arm.

With Lead III, we can see that the impulse is traveling from midpoint between the left arm and the left leg. Lead III is showing the difference of potential from the left arm and leg. It is not measuring whether the impulse is traveling toward or away from the right arm because it cannot tell that. It is only measuring the difference between left arm and left leg.

Your teacher probably wants you to memorize the leads by certain call-words. Once you hear "midpoint between left arm and left leg" or you hear "the difference between left arm and left leg" you are supposed to automatically think of Lead III.

Answer 3

it is lead AVR

III: is a lead obtained between a negative electrode placed on the left arm and a positive electrode placed on the left foot
AVR: is a lead obtained between the average signal obtained from three negative electrodes (left arm, left leg and right foot) and the signal obtained from a positive electrode placed on the right arm


sometimes books give diferrent information, the technique is check all the books and know what type of lead for that purpose was mentioned most, it was what my teacher said before

Answer 4

Did u pose this Q to your teacher?
She should give that point back to you for sure. You were just following textbook.
If she doesnt, take your inquiry of double-speak between the teacher and the textbook she supports only "sometimes" up another level to other teachers or higher ups. Honestly, its that big of a deal. Bc' they cannot give textbooks and disregard the info within and screw with peeps minds!!!!! PURSUE!!!!

Answer 5

To the method which gets the electrocardiogram the both hands (1st induction), the right hand and the left foot (2nd induction), the left hand and the left foot (3rd induction) ticket [cwun_ci] induction (grade pole induction () * there is also a chest induction back on) outsides.