EKG

Question 1

What is the electrode we care about the most and what is its polarity?

Answer 1

sensing electrode, positive polarity (also called the positive sensing electrode)

Question 2

If the wave of depolarization is generally moving ____ the positive sensing electrode, the electrode will record a ______ deflection _____ the isoelectric line on the EKG paper

Answer 2

toward, positive, above

Question 3

What happens inside the cell during depolarization and why?

Answer 3

inside becoming more positive due to NA influx

Question 4

If the wave of depolarization is moving ____ ____ the positive sensing electrode, then the electrode will record a _____ deflection ____ the isoelectric line on the EKG paper

Answer 4

away from, negative, below

Question 5

If the wave of depolarization moves ______ to the line of sight of the positive sensing electrode, the sensing electrode will record a _____ _____ on the EKG paper

Answer 5

perpendicular, biphasic tracing

Question 6

If the wave of repolarization is moving ____ the positive sensing electrode, then it will inscribe a ____ deflection below the isoelectric line on the EKG paper

Answer 6

toward, negative

Question 7

If the wave of repolarization moves ____ ____ the positive sensing electrode, then it will inscribe a _____ deflection above the isoelectric line

Answer 7

away from, positive

Question 8

If a wave of repolarization moves _____ past the line of sight of the positive sensing electrode, then it will inscribe a _____ deflection on the EKG paper

Answer 8

perpendicular, biphasic

Question 9

A small 1mm box has time equal to:____
A big 5 mm box has time equal to: ____

Answer 9

0.04 secs, 0.2 secs

Question 10

Describe how the heart generates contractions/electrical activity? (describe the picture)

Answer 10

Question 11

If we are using the cardiac ruler method to calculate heart rate, what wave are you looking for and what is your countdown?

Answer 11

Start with one R wave and see where the next R wave falls, count down is 300, 150, 100, 75, 60, 50, 43, 37, 33, 30

Question 12

Which lead is the one we are mainly looking at when cardiac monitoring?

Answer 12

Lead II

Question 13

Which leads are the inferior leads and which vessels can they detect to be occluded?

Answer 13

II, III, aVF and the vessels would be the RCA (right coronary artery), PDA (posterior descending artery), circumflex of the left coronary artery

Question 14

Which are the lateral wall leads and what vessel(s) could they detect to be occluded?

Answer 14

aVL and Lead I, RCA most commonly occluded

Question 15

t/f, the wave form for atrial repolarization is usually not seen as it it is hidden in the QRS?

Answer 15

true, is hidden so not seen

Question 16

The ___ represents the wave of depolarization that spreads from the SA node throughout the atria

Answer 16

P-wave

Question 17

What tends to make up a normal P-wave?

Answer 17

smooth and rounded, 2.5 mm in height, no more than 0.11 sec in duration

Question 18

What does an PR interval that is greater than 0.2 seconds indicate?

Answer 18

indicates a conduction defect usually within the AV node —> first degree heart block

Question 19

_______ represents ventricular depolariztion and generally represent electrical activity in __ ___

Answer 19

QRS complex, L ventricle

Question 20

____ is part of repolarization of ventricles and depression of this segment represents _____ _____

Answer 20

ST segment, myocardial ischemia

Question 21

QT interval represents ____ ___ ___ - the time from ventricular depolarization (activation) to repolarization (recovery)

Answer 21

total ventricular activity

Question 22

What are the steps to analyzing a rhythm strip?

Answer 22

1. Rate
2. Rhythm (should be regular)
3. Waveforms
4. Intervals: PR, QRS, QT
5. Overall appearance (ST, T waves)
6. Interpret