What is the management approach for patients with early Cardiac Implantable Electronic Devices (CIED), specifically pacemakers?

Management of Early Cardiac Implantable Electronic Devices (Pacemakers)

All patients with newly implanted pacemakers require a systematic four-step preoperative evaluation: confirm device presence, define device type, determine pacing dependence, and assess device function. 1

Preoperative Evaluation Framework

Step 1: Establish Device Presence

• Conduct focused history by interviewing the patient, reviewing medical records, and examining available chest x-rays, electrocardiograms, or rhythm strips 1
• Perform focused physical examination by checking for surgical scars and palpating for the device generator 1
• Case reports demonstrate that incomplete preoperative examination can lead to inhibited CIED function and asystole, making this step critical despite the absence of controlled trials 1

Step 2: Define Device Type

• Obtain the manufacturer's identification card from the patient or other available sources 1
• Order chest x-rays if no other data are available—most current CIEDs have an x-ray code identifying the manufacturer 1
• Refer to supplemental resources including manufacturer databases, pacemaker clinic records, or cardiology consultation 1

Step 3: Determine Pacing Dependence

This is the most critical determination for patient safety. Pacing dependence is established by one or more of the following 1:

• Verbal history or medical record documentation of bradyarrhythmia causing syncope or other symptoms requiring CIED implantation 1
• History of successful atrioventricular nodal ablation that resulted in CIED placement 1
• CIED evaluation showing no spontaneous ventricular activity when the pacing function is programmed to VVI mode at the lowest programmable rate 1

Step 4: Assess Device Function

• Ideally perform comprehensive device interrogation through consultation with a cardiologist or CIED service 1
• At minimum, confirm pacing impulses are present and create a paced beat (mechanical systole with pacemaker impulse) 1
• Consider contacting the manufacturer for perioperative recommendations 1

Preoperative Preparation

Electromagnetic Interference (EMI) Assessment

Determine whether EMI is likely during the planned procedure, as electrocautery, radiofrequency ablation, and MRI are associated with significant EMI risk 1

Device Reprogramming Considerations

• Consider reprogramming to asynchronous pacing mode if EMI is anticipated, particularly for pacemaker-dependent patients 1, 2
• Disable rate-adaptive functions and special algorithms that may be affected by EMI 1
• Ensure temporary pacing and defibrillation equipment is immediately available before, during, and after any procedure 1

Surgical Planning

• Advise the surgical team to consider bipolar electrocautery or ultrasonic scalpel to minimize EMI effects on the pulse generator or leads 1
• Position electrosurgical receiving plates so the current pathway does not pass through or near the CIED system 1

Intraoperative Management

Continuous Monitoring Requirements

Both continuous ECG and peripheral pulse monitoring are mandatory for all CIED patients receiving general or regional anesthesia, sedation, or monitored anesthesia care 1

• Display the patient's electrocardiogram continuously from the beginning of anesthesia until transfer out of the anesthetizing location 1
• Monitor peripheral pulse continuously through palpation, auscultation, intra-arterial pressure tracing, ultrasound, or pulse oximetry 1
• If unanticipated device interactions occur, consider discontinuing the procedure until the interference source can be eliminated or managed 1

EMI Management During Electrocautery

• Use short, intermittent, and irregular bursts at the lowest feasible energy levels 1
• Avoid proximity of the cautery's electrical field to the pulse generator or leads 1
• Keep electrical devices away from pacemakers and use only brief bursts of electrical current at the lowest possible amplitude 2

Monitoring Protocol for Dual Chamber Pacemakers

Baseline Assessment

• Obtain a non-magnet ECG strip to determine if the patient displays intrinsic rhythm or is being paced 3
• Assess normal sensing for both chambers by observing if intrinsic cardiac events appropriately inhibit pacing output 3
• Characterize the underlying atrial mechanism (sinus rhythm, atrial fibrillation, atrial tachycardia) 3

Capture Function Testing

• Apply a magnet over the pacemaker to convert it to asynchronous pacing mode (typically DOO for dual chamber) 3
• Obtain a magnet-applied ECG strip to verify effective capture of both chambers 3
• Assess the magnet rate and compare with previous values to detect battery depletion 3

Follow-up Monitoring Frequency

• Check newly implanted devices twice in the first 6 months 3
• Monitor established dual-chamber pacemakers once every 6 months 3
• Perform continuous ECG monitoring for 12-24 hours after implantation to detect complications like lead dislodgement, which occurs in up to 16% of temporary epicardial pacing wires 3

Common Pitfalls to Avoid

• Do not assume the device will automatically function properly—incomplete preoperative examination has led to asystole in documented cases 1
• Do not delay necessary procedures due to CIED presence—proper preparation and monitoring allow safe perioperative management 1
• Be aware that large pacing artifacts may obscure QRS complexes, making it difficult to determine ventricular capture 3
• Watch for loss of pacemaker output from separated lead wires, depleted batteries, or oversensing 3
• Recognize that anesthetic-induced physiologic changes (cardiac rate, rhythm, or ischemia) may induce unexpected CIED responses 1