This document discusses considerations for surgery in patients with implantable cardioverter-defibrillators (ICDs) or pacemakers. Electrocautery can cause electromagnetic interference that temporarily or permanently affects the device's functioning by resetting modes, inhibiting pacing, or triggering ICD shocks. The impact depends on factors like device type, lead placement, and whether the patient relies on pacing. Evaluation involves assessing the device and settings. Measures like using bipolar cautery, maximizing distance between devices and cautery, and magnet placement can reduce risks. After surgery, devices may need reprogramming and checking.

1. A B H I L A S H
SURGERY IN PATIENTS WITH
ICD AND PACEMAKERS

2. • Interactions between the pacemaker and current
generated by electrocautery.
• Metabolic derangements, antiarrythmic agents and
anaesthetic agents on pacing and sensing
thresholds.

3. EMI – ELECTROMAGNETIC
INTERFERENCE
• Depends on the proximity of the ICD/ pacemaker.
• Amount of current generated
• Axis of the electrocautery and the pacemaker.

4. AFFECTS OF ELECTROCAUTERY ON THE
ICD OR PACEMAKER
1) temporary or permanent resetting to a different
pacing mode.
2) temporary or permanent inhibition of pacemaker
output;
3) an increase in pacing rate due to activation of the
rate-responsive sensor;
4) ICD firing due to activation by electrical noise;

5. IMPACT TO THE PATIENT
• Depends on
• patient is pacemaker dependent?
• whether the pacemaker has unipolar or bipolar leads.
• electrocautery is bipolar or unipolar
• relative distance from and orientation of the electrocautery
relative to the pacemaker and pacemaker lead

6. EVALUATION OF A PATIENT ON
PACEMAKER
• 1) determining the type of device
• 2) determining whether the patient is pacemaker
dependent for antibradycardia pacing
• 3) determining device programmed settings and
battery status

7. • pacemaker dependent- reprogram to an
asynchronous mode during surgery ,or a
magnet should be placed over the
device during surgery
• ICD- tachyarrhythmia treatment
algorithms programmed off before
surgery and turned on after surgery to
prevent unwanted shocks due to spurious
signals that the device might interpret as
ventricular tachycardia or fibrillation

8. MEASURES TO REDUCE EMI
• 1) bipolar electrocautery
• 2) short and intermittent bursts of electrocautery at
the lowest possible energy levels
• 3) maximization of the distance between the
electrocautery and the device
• 4) if a unipolar cautery is to be used, placement of
the ground patch in a position so as to minimize
current flow through the pacemaker or ICD device
• If cardioversion is needed keep the paddles as far
as possible from the pacemaker and preferrably
perpendicular to the axis of the pacemaker leads.

9. EFFECTS OF MAGNET PLACED
• FOR PACEMAKER – changes it to asynchronous
mode- delivers preprescribed pace.
• In dependent patients apply before operation to
be certain.
• Magnets will not change pacing function of ICD.
• In some cases magnets turn off the shock function
of the ICD.

10. AFTER SURGERY
• If reprogrammed for surgery should be
programmed back.
• Formal assessment of pacemaker/ICD by an expert.