Transcutaneous Pacing: Procedure

In the emergency department, most of the equipment needed for transcutaneous pacing is often contained in a predesignated “crash cart.” Successful initiation of transcutaneous pacing requires:

• ECG monitoring equipment with monitor and cables.
• ECG patches.
• Pulse generator unit.
• Pacer pads and cables.
• Analgesia and sedation medications.

Prior to the initiation of cardiac pacing, all patients should be placed on a continuous ECG monitor. This will aid in the diagnosis of the underlying dysrhythmia, as well as provide evidence of the cardiac response to pacing efforts.

Newer pacer/defibrillator units often have pacing functionality in addition to the standard defibrillating setting, obviating the need for a second generator unit for transcutaneous pacing. Current pacing pads often are available with attached pacing cables, as well as adhesive surfaces to optimize contact with the patient’s skin.

There are two placement configurations recommended for maximum cardiac response. One option is to center a pad over the apex of the heart and place the other on the right upper chest.

Alternatively, a pad may be placed over the V3 lead position, while the other is placed between the left scapula and the thoracic spine.

Transcutaneous pacing can be quite uncomfortable for patients who are conscious, as it requires the discharge of electrical impulses through the skin and chest wall muscles. Therefore, sedation and analgesia should be considered to help reduce this discomfort.

Side effects of sedation and analgesia can exacerbate the condition of patients with significant hemodynamic compromise, so extra care should be taken when dosing these patients.

The initial pacing rate should be set to 80 bpm with the current set to minimal output. Initially, pacer spikes may be visualized without resultant cardiac depolarization. The current can be increased by 5-10 mA at a time until a definite QRS complex and T wave is demonstrated following each pacer spike.

Check the patient’s pulse at this point to confirm that electrical “capture” results in physiologic hemodynamic response. This level is defined as the pacing threshold and will be found between 40 and 80 mA for most healthy patients. Final current output should be set to 5-10 mA above the threshold level to ensure continued capture.

Transvenous Pacing: Indications

The use of transvenous pacing is technically more difficult and invasive than transcutaneous pacing but can provide substantial benefit to the patient. Proper placement requires a knowledgeable practitioner. With appropriate training, emergency physicians can be proficient in this skill.