Pacer Pads, Transcutaneous Pacing, Bradycardia Management, Pad Placement, External Pacing vs Defib Pads, When to Use Pacing

Pacer Pads:

• What is Pacer Pads?
• Transcutaneous Pacing
• Bradycardia Management
• Pad Placement
• External Pacing vs Defib Pads
• When to Use Pacing

What is Pacer Pads?

Pacer pads are adhesive electrode pads used in emergency and clinical settings to deliver electrical impulses to the heart through the chest wall. These pads are typically connected to a defibrillator or cardiac monitor that has pacing capabilities. Their main purpose is to provide transcutaneous pacing when a patient is experiencing significant bradycardia or cardiac arrest where electrical stimulation of the heart is required.

The pads are designed to be quick to apply and compatible with both pacing and defibrillation functions, depending on the device. They come in adult and pediatric sizes, and their placement is crucial for effective pacing. Modern pacer pads are pre-gelled, radiolucent, and often marked for anterior-posterior or anterior-lateral positioning. Using pacer pads correctly can be lifesaving in situations where the heart requires external pacing support.

Transcutaneous Pacing

Transcutaneous pacing (TCP) is a non-invasive emergency procedure that uses pacer pads to deliver regular electrical impulses through the chest to stimulate the myocardium. It is most commonly used in unstable bradycardia when pharmacologic treatments such as atropine are ineffective or delayed. The goal is to temporarily maintain adequate heart rate and cardiac output until a more definitive treatment, like transvenous pacing, can be arranged.

The procedure involves placing pacer pads, setting the device to pacing mode, selecting a pacing rate (usually 60–80 bpm), and increasing the current until capture is achieved. Capture is confirmed by the presence of a pacing spike followed by a wide QRS complex and palpable pulse. Although effective, TCP can be uncomfortable, so sedation is recommended when time and patient status allow.

Bradycardia Management

In bradycardia management, transcutaneous pacing is part of the Advanced Cardiac Life Support (ACLS) algorithm. For patients with symptomatic bradycardia — such as hypotension, altered mental status, chest pain, or signs of shock — immediate interventions include airway stabilization, oxygen administration, IV access, and monitoring. Atropine is the first-line drug, but if it is ineffective, TCP is initiated.

Pacer pads are attached, pacing mode is activated, and electrical impulses are delivered at a sufficient current to achieve capture. This stabilizes the patient while preparations for more permanent pacing or pharmacologic interventions continue. In emergency situations, TCP can be initiated quickly and is a bridge to transvenous pacing, particularly in cases of AV block or sinus node dysfunction.

Pad Placement

Proper pad placement is critical for effective pacing. There are two primary configurations:

• Anterior–Posterior: One pad is placed on the left anterior chest, over the precordium, and the other on the back beneath the left scapula. This configuration provides a direct current path through the heart and is often preferred.
• Anterior–Lateral: One pad is placed below the right clavicle, to the right of the sternum, and the other is placed on the left side, mid-axillary line, at the level of the V6 lead.

Pads should be applied to clean, dry skin to ensure good contact. Excess hair may be shaved if it interferes with adhesion. Correct placement improves electrical capture and reduces skin burns or ineffective pacing.

External Pacing vs Defib Pads

Although both pacing and defibrillation use adhesive pads, pacing pads and defib pads serve different functions. Defibrillation pads are designed to deliver a high-energy shock to terminate life-threatening arrhythmias such as ventricular fibrillation or pulseless ventricular tachycardia. Pacing pads, in contrast, deliver lower, repetitive current to stimulate cardiac depolarization in bradycardia.

In many modern devices, the same pads are used for both pacing and defibrillation, depending on the selected mode. The machine automatically adjusts the current and energy output based on the function chosen. Knowing how to switch between pacing and defibrillation modes is essential in emergencies.

When to Use Pacing

Pacing is indicated in patients with unstable bradycardia who do not respond to atropine, or in high-degree AV block where conduction is severely impaired. Situations include sinus node dysfunction, second-degree type II AV block, third-degree AV block, or severe bradyarrhythmias leading to hemodynamic instability. It can also be used temporarily in certain procedural or perioperative situations where bradycardia is anticipated.

The decision to pace is based on the patient’s clinical presentation rather than heart rate alone. Prompt initiation of pacing can stabilize cardiac output, improve perfusion, and prevent cardiac arrest. Once stabilized, patients often require further evaluation, transvenous pacing, or permanent pacemaker placement depending on the underlying cause.