Investigation of hyfrecators and their in vitro interference with implantable cardiac devices.

Background: Guidelines exist for minimizing potential electromagnetic interference (EMI) with electrosurgical equipment in patients with cardiac rhythm management (CRM) devices. These guidelines encompass all electrosurgical devices but are not specific for hyfrecators.

Objective: To investigate the potential interference of CRM devices by hyfrecators.

Materials And Methods: Using a collagen-based saline gel, three implantable pulse generators (pacemakers) and three implantable cardioverter defibrillators were tested to measure the EMI from two commonly used hyfrecators. The six devices were tested using the hyfrecator under normal use settings and on maximum power.

Results: Hyfrecators did not interfere with defibrillators and affected pacemakers only when used in close proximity to the device. For the pacemakers, atrial inhibition was observed at a distance of 3 cm on maximum hyfrecator settings and 1 cm at normal use settings. Ventricular inhibition occurred in very close proximity to the device (<1 cm) or in direct contact.

Conclusion: Hyfrecators are safe to use in patients with defibrillators and can be used in pacemaker patients within 2 inches of the device perimeter.