Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Escape and Usurpation Escape: Predominant pacemaker slows, lower pacemaker takes over at slower rate. An escape beat is a beat that comes in after a pause Usurpation: Irritable lower pacemaker takes control and becomes new pacemaker at a faster rate, suppressing or inhibiting the previous pacemaker

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure 2-11 Escape

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure 2-12 Usurpation

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis EKG Paper Graph paper that EKGs are printed on Divided into small blocks 1 millimeter in height and width Counting horizontally measures time (intervals) Counting vertically measures amplitude

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure 2-13 EKG Paper

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis EKG Paper Delineations One small block is 0.04 seconds Five small blocks = one big block One big block = 0.20 seconds 25 small blocks = 1 second Five big blocks = 1 second 1500 small blocks = 1 minute 300 big blocks = 1 minute

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis 12-Lead EKGs and Rhythm Strips 12-Lead EKG: Printout of the heart’s electrical activity viewed from 12 different angles as seen in 12 different leads A lead is an electrocardiographic picture of the heart’s electrical activity Rhythm Strip: Printout of only one or two leads at a time

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure 2-14 (A) Single- and (B) double-lead rhythm strips.

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Benefit of Double-Lead Strips Both leads show the same rhythm, just viewed from two different angles Therefore both leads have the same rhythm, intervals, and heart rate

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Benefit of Double-Lead Strips Two leads provide twice the chance of identifying the rhythm. For example, P waves may not be visible in one lead, but are very clear in the other Having two leads shows how the same rhythm can look different in different leads

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure Lead EKG

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. EllisIntervals Measurement of time between the P-QRS- T waves and complexes Measurements allow determination of heart’s efficiency at conducting its impulses down the pathway

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. EllisIntervals PR: Measured from beginning of P to beginning of QRS QRS: Measured from beginning of QRS to its end QT: Measured from beginning of QRS to end of T wave

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Figure 2-16 Intervals

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Intervals Practice: Enlarged Rhythm Strip 1 PR__________ QRS__________ QT__________

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Intervals Practice: Enlarged Rhythm Strip 2 PR__________ QRS__________ QT__________

Copyright ©2012 by Pearson Education, Inc. All rights reserved. EKG Plain and Simple, Third Edition Karen M. Ellis Intervals Practice: Enlarged Rhythm Strip 3 PR__________ QRS__________ QT__________