Implanted cardiac defibrillators (ICDs) seem to generate (no pun intended) several different thoughts in regard to their use with cautery. Most of these concern patient safety. I would like to share some of the comments I've seen in the discussion forum regarding this issue.
* ICDs need to be done in the hospital and not the ambulatory surgery center (ASC).
* You can't use cautery on these patients unless the ICD is turned off.
* Patients need to be on a cardiac monitor for the procedure.
* A physician is responsible for placing the magnets to activate and deactivate the ICD.
* The patient must have cardiac clearance before the procedure, and a cardiologist needs to be available at the time of the procedure.
The following recommendations regarding ICD use were presented at Mercy Hospital in Des Moines, Iowa, by Iowa Heart. Iowa Heart is a group of 54 cardiologists, cardiothoracic surgeons, and vascular surgeons. They have 9 clinics and 30 satellite clinics throughout Iowa. In 2002, they issued a statement to the areas of the hospital that were faced with this dilemma. These areas included surgery, anesthesia, ambulatory surgery, and endoscopy. The statement was signed by W. Ben Johnson, MD, and Steven J. Bailin, MD, who are specialized in electrophysiology.
As you are aware, the practice of the Iowa Heart Center has been to program implantable cardioverter defibrillators (ICDs) 'off' immediately prior to procedures which utilize electrocautery. However we have since found that unless the cautery is used directly on the heart, the defibrillator is not detecting any external electromagnetic impulse that would cause inappropriate therapies or shocks from the device. We therefore will no longer deactivate ICDs prior to procedures using electrocautery except in the case of open thoracotomy procedures. However we do recommend that magnets be placed on ICDs for any procedures being performed above the waist. Magnet application over the ICD temporarily suspends detection of the device. In this 'magnet mode' the ICD will not interpret the electromagnetic interference from cautery as an arrhythmia since detection is suspended. Magnet application does not affect the programmed pacing mode. If device intervention is needed during or after the procedure, simply remove the magnet and VT/VF detection is resumed. We recommend that patients receive cardiac monitoring throughout the procedure and if the procedure to be performed is 'below the waist' a donut magnet be available. If the patient receives a shock during the procedure and cardiac monitoring does not reveal ventricular tachycardia or fibrillation, the magnet should be placed over the defibrillator to prevent further inappropriate shocks.
I recently spoke with Robert Hoyt, MD, who is a board-certified electrophysiologist with Iowa Heart. Dr. Hoyt has researched this topic. He stated when he tried to do a literature review, he found there was not a lot of printed data on this topic, so he did his own research. He presented an abstract of this in Copenhagen at the Congress Europace (Hoyt, Bailin, Johnson, Sorrentino, & Harstein, 2001).
I asked Dr. Hoyt if he thought it was safe to perform these procedures in an ASC or if they must be done at the hospital. He said that simply having an ICD should not preclude a patient from having the procedure done at an ASC; however, many of these patients have significant cardiac histories that may warrant a hospital setting. He said cardiac monitoring should be used, not only during the procedure, but in the holding area, especially if magnets were placed during the procedure and there is a chance of any arrhythmia.
Dr. Hoyt's research was performed with monopolar cautery. With the use of monopolar cautery, the current was thought to be safe below the waist. The electrical current is discharged from the cautery source, and when the grounding pad is placed on the thigh or gluteal area, the current path doesn't go near the ICD. When the cautery is used in procedures above the waist (he used the example of skin cancers on the face or chest), there is a chance the device could be triggered; but, again, if the grounding pad is low, it probably wouldn't be a problem when the cautery is used in short bursts.
There is still some concern about the use of bipolar devices in patients with an ICD. Usually with bipolar devices, the current leaves and returns through a designated spot (i.e., the tip of the probe). The concern comes if the patient comes in contact with something else metal, such as a bed rail. This may change the route of the current.
Many nurses on the discussion board expressed concern over who should be activating and deactivating the ICDs with the magnets. Does it need to be a physician, sales representative for the devices, or a nurse? Dr. Hoyt said anyone trained about these devices can perform this skill.
Acknowledgment
The author thanks Dr. Hoyt and the other cardiologists of Iowa Heart for their knowledge and guidance in this new technological area.
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