RT Book, Section
A1 Takayesu, James K.
A2 Cline, David M.
A2 Ma, O. John
A2 Cydulka, Rita K.
A2 Meckler, Garth D.
A2 Handel, Daniel A.
A2 Thomas, Stephen H.
SR Print(0)
ID 56271061
T1 Chapter 2. Arrhythmia Management
T2 Tintinalli's Emergency Medicine Manual, 7e
YR 2012
FD 2012
PB The McGraw-Hill Companies
PP New York, NY
SN 978-0-07-178184-8
LK accessemergencymedicine.mhmedical.com/content.aspx?aid=56271061
RD 2024/04/16
AB Some  variation  in  the  sinoatrial  (SA)  node  discharge  rate  is  common;  however,  if  the  variation  exceeds  0.12  second  between  the  longest  and  shortest  intervals,  sinus  arrhythmia  is  present.  The  electrocardiogram  (ECG)  characteristics  of  sinus  arrhythmia  are  (a)  normal  sinus  P  waves  and  PR  intervals,  (b)  1:1  atrioventricular  (AV)  conduction,  and  (c)  variation  of  at  least  0.12  second  between  the  shortest  and  longest  P–P  interval  (Fig.  2-1).  Sinus  arrhythmias  are  affected  primarily  by  respiration  and  are  most  commonly  found  in  children  and  young  adults,  disappearing  with  advancing  age.  Occasional  junctional  escape  beats  may  be  present  during  very  long  P–P  intervals.  No  treatment  is  required.