1. Aim of Guideline
1.1 To give guidance on the management of cardiac implantable electronic devices (CIED) pre and post operatively in elective and emergency (out of hours) surgery.
1.2 Concern mainly centres around inappropriate function of these devices where they are exposed to electromagnetic interference (EMI), such as with the use of diathermy.
1.2.2 For pacemaker patients who are pacing dependent (no underlying rhythm) there is concern the device might inappropriately interpret EMI as intrinsic cardiac signals/rhythm and withhold pacing.
1.2.3 For ICD patients there is concern that EMI could be misinterpreted as ventricular fibrillation or ventricular tachycardia and that the device could give innapropriate therapy, such as delivering a shock.
1.3 It should also be borne in mind that the presence of a CIED may be indicative of additional cardiac pathology which should be considered.
2. Preoperative Management of Implantable Cardiac Devices
2.1 Relevant History
Establish the following:
• Type of CIED; Insertable Cardiac Monitor/Loop Recorder, Pacemaker, CRT-P, ICD or CRT-D.
• Manufacturer and model. If the patient is known to us this should be available on Epic or else patients should have an ID card with this information.
• If not followed up at receiving hospital, then contact should be made with the cardiac department of the hospital responsible for follow up, and the above information should be sought. A record of this information should be put on Epic under Media.
• Reason for implant and the underlying rhythm.
• The date of the last check and anything significant.
• For ICD or CRT-D; if, and how often therapy has been delivered.
• Location of CIED (typically left pre-pectoral, but not always).
• Any associated cardiac pathology, including any recent evaluation of cardiac function particularly for ICD and CRT devices.
2.2 Pacemakers
• For surgery above the umbilicus where diathermy will be used and where patients are pacing dependent, then reprogramming the pacemaker to an asynchronous mode should be considered. For those who are not dependent, reprogramming should not be necessary.
• For surgery below the umbilicus (taking into consideration location of pacemaker) there is less indication to reprogramme the device. A cardiac physiologist can advise. Patients should be monitored and a magnet readily available if needed.
• For endoscopy patients who are pacing dependent, then reprogramming the pacemaker to an asynchronous mode should be considered. For those who are not dependent, reprogramming should not be necessary.
• An asynchronous mode will provide continuous pacing, regardless of other signals to the device (including their own intrinsic cardiac signals) and thus mitigates concern regarding EMI from diathermy. However, asynchronous pacing modes can also be pro-arrhythmic so patient history should be considered before reprogramming.
• Asynchronous modes should be programmed pre-operatively in the anaesthetic room/endoscopy suite by the cardiac physiologist who can best determine which mode and rate is suitable and safest for the patient. Post surgery/endoscopy baseline settings should be restored by the cardiac physiologist.
• For patients with pacemakers where an asynchronous mode is needed but no cardiac physiologist is available such as in an emergency or out of hours a magnet can be placed.
• When a magnet is applied to a PPM it usually reverts to an asynchronous mode: VOO in single chamber pacemakers and DOO in dual chamber systems at a rate specific to the manufacturer. This can be less ideal than manual reprogramming to an asynchronous mode where the rate can be selected manually.
• However, it may also initiate a diagnostics function. The pacemaker should revert to programmed baseline settings upon removal of the magnet.
• Bipolar diathermy is preferable to monopolar for all patients with CIEDs. Electrodes should be positioned appropriately (so the pathway/return electrode is as far away from the device as possible). Short bursts are recommended.
• The cardiac physiologist must write a report that includes what settings were changed pre surgery/procedure and that settings were restored to baseline/clinically indicated settings post procedure.
• All patients must be continuously monitored with cardiac monitoring, regardless of if the pacemaker has been reprogrammed and regardless of underlying rhythm.
• A magnet must always be available for surgeries and endoscopy procedures.
2.3 ICD/CRT-D
• For all surgeries where diathermy use is anticipated, ICDs should be deactivated.
• Patients with ICDs don't typically have a bradycardia indication but asynchronous pacing may be necessary if patients are pacing dependent in addition to deactivation of the ICD. The cardiac physiologist will determine the best settings for surgery and programme accordingly.
• For CRT-D patients the above applies.
• Deactivation of ICDs and any reprogramming should be programmed pre-operatively in the anaesthetic room/endoscopy suite by the cardiac physiologist. Post surgery/endoscopy baseline settings should be restored by the cardiac physiologist.
• Deactivation of ICDs can ONLY be carried out in anaesthetic room/endoscopy suite associated with the room/theatre of that procedure.
• Reactivation/return to baseline settings can occur in PACU / recovery.
• Placing a magnet over an ICD will deactivate therapies (shocks) for the duration that it is placed over the ICD. If this is needed, then it should be secured in place for the duration of the procedure with surgical tape. Post procedure removing the magnet will restore normal settings. Note that for Biotronik devices if the magnet is placed for longer than 8 hours the ICD will revert to normal settings, so the magnet will need to be removed and then replaced over the ICD to keep therapies deactivated.
• The ICD might emit an alarm or vibrate when placing a magnet over it.
• Bipolar diathermy is preferable to monopolar for all patients with CIEDs. Electrodes should be positioned appropriately (so the pathway/return electrode is as far away from the device as possible). Short bursts are recommended.
• The cardiac physiologist must write a report that includes what settings were changed pre surgery/procedure and that settings were restored to baseline/clinically indicated settings post procedure.
• All patients must be continuously monitored, and the patient must have defibrillator pads placed and be attached to an external defibrillator. Pads should not be placed over the ICD. The cardiac physiologist will not deactivate the device unless the patient is fully monitored and is attached to an external defibrillator.
• A magnet must always be available for surgeries and endoscopy procedures.
• It is imperative that the patient has their ICD reactivated post surgery/procedure. Responsibility for ensuring this has been carried out remains with the clinical team looking after the patient, not the cardiac physiologist.
3. Organising Cardiac Physiology Support
3.1 Elective surgery
• POAN to inform the anaesthetist involved of the above via the anaesthetic opinion form
• POAN to inform the cardiac physiologists via email pre-operatively, with the relevant patient and clinical details, and the date and time of surgery. Cardiac physiologists will reply to inform if reprogramming will be needed or not.
• For Frimley Park patients email the Frimley pacing email and for Wexham Park and Heatherwood patients email the Wexham Park pacing email.
• Plan elective surgery that will start and finish within normal working hours
(08:30 – 16.30) to ensure cardiac physiologist availability for programming of CIEDs both before and after surgery/procedure.
3.2 Emergency / out of hours surgery
• Contact cardiology registrar or consultant for advice
• For patients with pacemakers that are pacing dependent and where diathermy is to be used, a magnet can be placed over the device which will provide continuous fixed pacing at the manufacturer’s rate.
• For patients with pacemakers who are not pacing dependent, no magnet should be placed, but one should be available should the device become inhibited, and the patient need pacing.
• For ICDs a magnet should be placed over the device (see section 2.3 for details on magnet application).
• Patients should be monitored at all times throughout the surgery, regardless of if a magnet is being applied.
• Post procedure upon removing a magnet the CIED should return to normal function.
• At FPH a magnet is kept in the nurses’ station and crash trolley in CCU; both crash trolleys in ICU; the main crash trolley in ED, theatre reception and in the controlled drugs cabinet in theatre 7.
• At WPH magnets are kept in the CCU crash trolley, in the Cardiology Investigations Unit and the Emergency Department and in the controlled drug cabinet in theatre 4 (emergency theatre)
• At Heatherwood a magnet is kept in the crash trollies in Recovery and theatre 6
3.3 Contra-indications: specific procedures
Seek advice from the cardiology department (pacing physiologist/ electrophysiologist) with regard to suitability and planning for:
• Radiofrequency ablation
• Tissue expanders in breast surgery
• Electroconvulsive therapy
• Radiation therapy
• Extracorporeal shock wave lithotripsy
• Diagnostic radiation