Pacemaker Misinformation in the Perioperative Period: Programming Around the Problem

Pacemaker-driven Tachycardia Induced by Electrocardiograph Monitoring in the Recovery Room

Monitoring devices are known to induce tachycardia in minute-ventilation rate-responsive pacemakers. This is because some monitoring devices measure the same parameter as do the pacemakers (change in thoracic impedance). Hence, the biological signal to the pacemaker is increased and is misconstrued as increased minute ventilation causing tachycardia which resolves when the monitoring device is removed. Whilst this could occur for all minute-volume rate responsive pacemakers, most reported interactions have been with the Telectronics META series. We present a case of an interaction between a Telectronics Tempo DR pacemaker (St. Jude Medical) and an Agilent Patient Care System (Philips). Failure to recognise the true nature and cause of such tachycardias may lead to mismanagement of the patient, including the inappropriate use of cardio-active medications.

Perioperative management of cardiac rhythm assist devices in ambulatory surgery and nonoperating room anesthesia

PURPOSE OF REVIEW

Patients with cardiac implantable electronic devices (CIEDs) frequently undergo various surgical procedures and in the past perioperative management involved only placing magnet over the device. New programming features, development of implantable cardiac defibrillator (ICD), cardiac resynchronization therapy, and increasing complexity of the operating room equipment have led to new sources of electromagnetic interference (EMI). A comprehensive understanding of the CIED is necessary to provide a timely and optimal care to the patients.

RECENT FINDINGS

Technological advancements and direct implantation of the transvenous implantable cardiac defibrillators into the heart have led to less clear lines between the pacemakers and the ICD. Subcutaneous ICD as well as the leadless transcatheter deployed intracardiac pacemaker development has complicated the issue further.

SUMMARY

Rapidly developing technologies and increasing number of patients with these devices coming for noncardiac surgeries necessitate continuous education of the anesthesia team regarding perioperative management of such devices.

Implantable Devices: Assessment and Perioperative Management

Technology is the prominent feature of the twenty-first century, including in medicine. There are very few organs that cannot be stimulated, shocked, or infused. With more and more implantable devices being approved for clinical use, anesthesiologists have to regularly take care of patients who have these devices. An understanding of the devices, the associated comorbidities, and the perioperative risks is crucial for safe management of these patients. Cardiac devices are discussed in some detail; neurostimulators and other implantable devices are briefly described. The principles of assessment and management are similar for all patients with implanted devices.

Monitor-induced tachycardia in a patient with a rate-responsive pacemaker

A patient with a ventricle-paced, ventricle-sensed and inhibited, respiratory rate-responsive pacemaker presented for orthopaedic surgery. She had been operated upon recently without any adverse effects. In the recovery unit her electrocardiograph showed a paced ventricular tachycardia of about 140 beats x min(-1) without any other adverse sign or symptom. Although this tachycardia initially decreased to 70 beats x min(-1) after about 30 min, it later rose again to 140 beats x min(-1). A pacemaker technician was consulted, who suggested that there may be interference between the bioelectric impedance signals of the patient monitoring system that was being used to measure respiratory rate and the pacemaker's own measurement systems.