How do you manage a permanent Implantable Cardioverter-Defibrillator (ICD) during Coronary Artery Bypass Graft (CABG) surgery?

Management of Permanent ICDs During CABG Surgery

For patients with permanent ICDs undergoing CABG surgery, preoperative device interrogation and reprogramming to suspend antitachyarrhythmia functions is strongly recommended to prevent inappropriate ICD therapies from electromagnetic interference (EMI). 1

Preoperative Management

1. Establish device details:

   • Confirm device type and location through patient records, physical examination, and chest X-rays
   • Determine pacemaker dependency status
   • Obtain manufacturer information and recent device settings 1

2. Device interrogation and reprogramming:

   • Consult with cardiology or device specialist for comprehensive evaluation
   • For pacemaker-dependent patients: Program to asynchronous mode (e.g., VOO, DOO)
   • For all ICD patients: Suspend antitachyarrhythmia functions 1
   • Disable special algorithms including rate-adaptive functions

3. Avoid routine magnet use:

   • The ASA Task Force cautions against routine magnet use over ICDs as response varies by manufacturer
   • Some ICDs may have no magnet response or can be permanently disabled by magnet application 1
   • Magnets may fail to inhibit ICD sensing of EMI in some cases 2

Intraoperative Management

1. Monitoring requirements:

   • Continuous ECG monitoring
   • Continuous peripheral pulse monitoring (arterial line, pulse oximetry, or palpation) 1

2. EMI minimization strategies:

   • Position electrocautery grounding pad away from the generator and leads
   • Use bipolar electrocautery or ultrasonic (harmonic) scalpel when possible
   • If monopolar cautery is necessary:
     • Use short, intermittent, irregular bursts at lowest feasible energy
     • Keep cautery at least 15 cm from device 1
   • Avoid direct contact between surgical instruments and the pulse generator or leads 1

3. Emergency defibrillation/cardioversion preparation:

   • Have external defibrillator immediately available
   • Position defibrillation pads/paddles as far as possible from pulse generator
   • Use anterior-posterior positioning when possible
   • For emergency defibrillation in patients with magnet-disabled ICDs:
     • Remove all sources of EMI
     • Remove magnet to re-enable antitachyarrhythmia therapies
     • If ICD function is not restored, proceed with external defibrillation 1

Postoperative Management

1. Immediate postoperative period:

   • Continue cardiac monitoring
   • Keep temporary pacing and defibrillation equipment available 1

2. Device interrogation and restoration:

   • Interrogate device to check for any parameter changes or recorded events
   • Restore all antitachyarrhythmia therapies
   • Ensure all device settings are appropriate 1
   • Postoperative checks may not be needed in low-risk situations (appropriate preoperative check, no EMI-generating devices used, no blood transfused, no perioperative reprogramming) 1

Common Pitfalls and Caveats

• Failure to identify device type: Always confirm whether the patient has a pacemaker or ICD before surgery
• Overreliance on magnets: Magnet response varies by manufacturer and can be affected by programming and battery life 1
• Inadequate EMI precautions: Even with device reprogramming, minimizing EMI is essential
• Delayed device restoration: Failure to restore antitachyarrhythmia functions postoperatively could leave patients vulnerable to life-threatening arrhythmias

By following these guidelines, the risk of adverse events related to ICD function during CABG surgery can be significantly reduced, ensuring optimal patient safety throughout the perioperative period.