Atrioventricular Blocks (AV Block)

Treatment

• Second Degree (if symptomatic)
  
• Atropine 
• 0.5mg every 5 minutes, max 3mg total
• Transcutaneous pacing 
• Always place pads in Mobitz II
  
• Pace if unresponsive to atropine
  
• Transvenous pacing if transcutaneous unsuccessful
• 0.2-20 mA
  
• Permanent Pacemaker
  
• Third Degree 
• Stable
• Apply transcutaneous pads
• Same treatment as Mobitz II
• Unstable
• Transcutaneous pacing until transvenous placement

 Types of AV Block

• First Degree
• PR interval > 200ms
   
• Second Degree type 1 (Mobitz I)
  
• PR intervals progressively lengthen before dropped beats
   
• Second Degree type 2 (Mobitz II)
• Fixed PR intervals before dropped beats
  
• Third Degree (complete)
• Total dissociation between P waves and QRS