Basic Dysrhythmias Study Guide

Basic Dysrhythmias Study Guide

, Basic Dysrhythmias Study Guide

 Be able to label the normal conduction system of the heart



Normal Conduction System
- Sinus Node (SA Node)
- AV Node
- Bundle of His
Purkinge Fibers - Left & Right Bundle Branches
- Purkinge fibers




 Know the inherent rates (pg 10-12)
o SA Node (normal pacemaker) 60-100
o AV Node (backup pacemaker) 40-60
 Ventricular cells (final pacemaker) 20-40

 Know that CARDIAC OUTPUT is one of our key nursing priorities
 Know the components of the EKG tracing, intervals, and what they represent




o P wave represents atria O QRS represents ventricles
o P and T wave should be upright and rounded O U wave may be seen after a T wave
o Normal PR interval: 0.12-0.20 O Normal QRS interval: 0.06-0.12
o ST segment should be isoelectric – ST elevation or depression represents injury/ischemia
o QT interval may be measured with certain medications or conditions – normal QT interval should be
less than half the distance between two consecutive R waves (R to R interval)

 Know how to measure
o Normal PR interval: 0.12-0.20
o Normal QRS interval: 0.06-0.12
EKG Grid
o Each small box = 0.04 seconds
o Each large box = 0.20 seconds (5 small boxes)