Medical/Surgical Nursing Dysrhythmia Interpretation
1. Impulse generated by SA node <Answer>
60-100 BPM P wave indicated
Mitral and tricuspid valves open
2. Atrioventricular node <Answer> Located in inferior right atrium near the
ostium of the coronary sinus
Delays impulses for 0.04 seconds
Prevents ventricles from contracting too quickly (more filling= increased CO, in-
creased preload
Allows cardiac muscle to stretch to fullest peak (Starlings Law)
3. Bundle of HIS <Answer> Tract of tissue that extends into ventricles
next to septum Promotes rapid impulse conduction through ventricle
Impulse travels faster down the left bundle (left ventricle supply) then to the right
Permits both ventricles to contract simultaneously
4. Purkinje Fibers <Answer> Extends from Bundles into the endocardium
Conducts impulses rapidly through muscle to assist with depolarization and contrac-
tions
5. ECG diagnoses <Answer> Chamber
enlargement Conduction Abnormalities
Dysrhythmia
Myocardial Infarction
Effects of Medications
6. First step with potential MI <Answer> Attach to monitor
7. Large EKG boxes <Answer> 5mm high and 0.20 seconds long
8. Small EKG boxes <Answer> 1mm high and 0.04 seconds long
9. EKG <Answer>
5 boxes
15 boxes
30 boxes <Answer> EKG <Answer>
1 second
3 seconds
,6 seconds (Multiply beats by 10 to get bpm)
, 10. P wave <Answer> Needs to preced QRS complex to be
considered sinus Atrial depolarization (SA node fires)
Smooth, Rounded, Small
11. QRS Complex <Answer> Ventricular
Depolarization Ventricular contraction
12. T Wave <Answer> ventricular repolarization
13. P-R interval <Answer> Transmission of impulse from SA node to the AV node
(Can be slowed by an AV block or with medication <Answer> beta blockers and
calcium channel blockers)
14. S-T Segment <Answer> End of ventricular depolarization and beginning of
repolarization
**Reflects ischemia, cardiac injury, potassium abnormalities
15. Q-T interval <Answer> used to measure the effect of cardiac
medications Long QT syndrome <Answer> takes too long to
repolarize
16. U wave <Answer> Late depolarization of the ventricles (cannot normally see
unless very bradycardic < 70)
17. Step 1 Strip Analysis <Answer> Rhythm <Answer> Evaluate the Atrial
and Ventricular Rhythm Regular P to P? R to R?
18. Step 2 Strip Analysis <Answer> Rate <Answer>
Determine the ventricular rate <Answer> Count the # of QRS
complexes in a 6 second (30 box) strip Multiply by 10
19. Step 3 Strip Analysis <Answer> P wave
<Answer> Present or Absent indication of sinus or
not (If initiated by the SA node)
20. Step 4 Strip Analysis <Answer> PR interval <Answer> Calculate <Answer>
Count # of squares between the P wave and beginning of the QRS complex
Multiply by 0.04
Normal P-R interval is 0.12-0.20 sec
21. Normal P-R interval <Answer> 0.12-0.20 seconds (3-5 small boxes)
22. Step 5 <Answer> QRS complex <Answer> Calculate duration <Answer>
Count the number of squares between the beginning and the end of the QRS
Normal < 0.12
(less than 3 small boxes)
23. Normal QRS <Answer> < 0.12 seconds, less than 3 small boxes
24. Step 6 Strip Analysis <Answer> T wave and ST Segment <Answer> 1.
1. Impulse generated by SA node <Answer>
60-100 BPM P wave indicated
Mitral and tricuspid valves open
2. Atrioventricular node <Answer> Located in inferior right atrium near the
ostium of the coronary sinus
Delays impulses for 0.04 seconds
Prevents ventricles from contracting too quickly (more filling= increased CO, in-
creased preload
Allows cardiac muscle to stretch to fullest peak (Starlings Law)
3. Bundle of HIS <Answer> Tract of tissue that extends into ventricles
next to septum Promotes rapid impulse conduction through ventricle
Impulse travels faster down the left bundle (left ventricle supply) then to the right
Permits both ventricles to contract simultaneously
4. Purkinje Fibers <Answer> Extends from Bundles into the endocardium
Conducts impulses rapidly through muscle to assist with depolarization and contrac-
tions
5. ECG diagnoses <Answer> Chamber
enlargement Conduction Abnormalities
Dysrhythmia
Myocardial Infarction
Effects of Medications
6. First step with potential MI <Answer> Attach to monitor
7. Large EKG boxes <Answer> 5mm high and 0.20 seconds long
8. Small EKG boxes <Answer> 1mm high and 0.04 seconds long
9. EKG <Answer>
5 boxes
15 boxes
30 boxes <Answer> EKG <Answer>
1 second
3 seconds
,6 seconds (Multiply beats by 10 to get bpm)
, 10. P wave <Answer> Needs to preced QRS complex to be
considered sinus Atrial depolarization (SA node fires)
Smooth, Rounded, Small
11. QRS Complex <Answer> Ventricular
Depolarization Ventricular contraction
12. T Wave <Answer> ventricular repolarization
13. P-R interval <Answer> Transmission of impulse from SA node to the AV node
(Can be slowed by an AV block or with medication <Answer> beta blockers and
calcium channel blockers)
14. S-T Segment <Answer> End of ventricular depolarization and beginning of
repolarization
**Reflects ischemia, cardiac injury, potassium abnormalities
15. Q-T interval <Answer> used to measure the effect of cardiac
medications Long QT syndrome <Answer> takes too long to
repolarize
16. U wave <Answer> Late depolarization of the ventricles (cannot normally see
unless very bradycardic < 70)
17. Step 1 Strip Analysis <Answer> Rhythm <Answer> Evaluate the Atrial
and Ventricular Rhythm Regular P to P? R to R?
18. Step 2 Strip Analysis <Answer> Rate <Answer>
Determine the ventricular rate <Answer> Count the # of QRS
complexes in a 6 second (30 box) strip Multiply by 10
19. Step 3 Strip Analysis <Answer> P wave
<Answer> Present or Absent indication of sinus or
not (If initiated by the SA node)
20. Step 4 Strip Analysis <Answer> PR interval <Answer> Calculate <Answer>
Count # of squares between the P wave and beginning of the QRS complex
Multiply by 0.04
Normal P-R interval is 0.12-0.20 sec
21. Normal P-R interval <Answer> 0.12-0.20 seconds (3-5 small boxes)
22. Step 5 <Answer> QRS complex <Answer> Calculate duration <Answer>
Count the number of squares between the beginning and the end of the QRS
Normal < 0.12
(less than 3 small boxes)
23. Normal QRS <Answer> < 0.12 seconds, less than 3 small boxes
24. Step 6 Strip Analysis <Answer> T wave and ST Segment <Answer> 1.
