Cardiac Pacemaker

Used when intrinsic cardiac electrical activity is inappropriately slow or absent
Sense electrical activity of heart and deliver electrical impulses to the heart.

 

Pulse generators contain:

  • Battery (5-8 year lifespan)
  • Output circuit
  • Timing circuit
  • Sensing circuit

 

Types of pacemaker: Pacemaker Code

Chamber paced Chamber sensed Response to sensed event Rate-responsive features Anti-tachycardic facilities
Atrium
Ventricle
Dual

Atrium
Ventricle
Dual
NOne
Triggered
Inhibited
Dual (Atrial triggered, ventricle inhibited)
NOne
Reversed
R - rate responsive pacemaker Pacing
Shock
Dual - Pacing & shock

 

 

Insertion technique

Endocardial wiring:

  • Insertion into cephalic, axillary or subclavian vein
  • Advanced into atrium/ventricle
  • Pulse generator placed subcutaneously

Extracardial wiring:

  • Placed epicardially onto heart surface
  • Used in paediatrics where wires may become too short as heart grows

Complications:

  1. General/insertion
    • Infection
    • Wound dehiscence
    • Thrombophlebitis
  2. Specific
    • Electrical problems: failure to capture, output, sense, trigger etc

Preparation

  • FBC, Clotting screen
  • Antibiotics: Flucloxacillin 500mg IM + Benzylpenicillin 600mh IM / 20min before, 1, 6 hours after