ACLS review: Bradycardia part 1

Management of Bradycardia

Causes of Bradycardia

·         Acute myocardial infarction

·         Drugs:  blockers, digoxin, Amiodarone

·         Increased intracranial pressure

·         Sick sinus syndrome

·         Hypothermia

·         Hypothyroidism

 

Common Bradycardic Rhythms

·         Sinus bradycardia

·         NSR with sinus arrest

·         2^nd degree heart block type II

·         3^rd degree heart block

 

Sinus Bradycardia

 

 

 

ECG Characteristics 

Rate: The atrial and ventricular rates are equal; the heart rate is less than 60 beats per minute

Rhythm: the rhythm is regular

P Wave: The P waves are uniform. There is one P wave in front of every QRS complex.

PRI: 0.12 - 0.20 seconds and constant.

QRS: less than 0.12 seconds

Sinus Arrest

ECG Characteristics

Rate: The rate varies according to the number and length of pauses

Rhythm: The rhythm is regular except during pauses

P Wave: The P waves are uniform. There is one P wave in front of every QRS complex

PRI: 0.12 - 0.20 seconds and constant.

QRS: less than 0.12 seconds

Second Degree Heart Block Type II

ECG Characteristics

Rate: Atrial rate is typically normal. Because many of the atrial impulses are blocked, the ventricular rate will be in the bradycardia range, usually with a 2 - 1, 3 - 1, or a 4 - 1 conduction rate.

Rhythm: If the conduction rate is consistent, the R - R interval will be constant, and the rhythm will be regular. If the conduction ratio varies, the R - R will be irregular.
P Wave: Upright and uniform. There are more P waves than QRS complexes
PRI: Will be constant on conducted beats.
QRS: less than 0.12 seconds

Reviewed 2/28/16