Preanesthesia Evaluation and Implantable Cardioverter-Defibrillator Reprogramming

In addition to evaluating and optimizing any comorbid diseases in the ICD patient, every ICD should undergo preoperative interrogation. These devices store considerable data regarding the occurrence of dysrhythmias. Because antitachycardia pacing is well tolerated, many patients are not aware of this intervention. For any patient scheduled to undergo an elective procedure, the onset of new dysrhythmias warrants delay of the case and investigation of the problem ( Fig. 35-8 ).

Determination of the need for elective replacement for battery depletion in ICDs is more complicated than in pacemakers. Since some ICDs have two batteries, predicting battery depletion based upon battery voltage is difficult. In general, the manufacturer should be consulted for any device with a "charging time" in excess of 12 seconds.

ALL ICDs should have their antitachycardia therapy disabled prior to the induction of anesthetic and commencement of the procedure (see ACC Guidelines ^[3] ). The use of monopolar ESU can cause inappropriate shocks. Casavant and co-workers found a stored electrogram sequence in an ICD (similar to Fig. 35-8 ) suggesting that it had misinterpreted monopolar ESU during dermatologic facial surgery as VF, ^[86] and Figure 35-9 shows one of the 73 VT detections that occurred during an orthopedic procedure.

The comments in the pacing section (including Appendix 1 and Table 35-5 ) apply here for any ICD with antibradycardia pacing. Many ICDs have no noise reversion behavior, so ESU-induced ventricular oversensing might lead to nonpacing in the patients who are dependent upon their ICDs for pacing.