Bradycardia and Pacing

Faisal Alruways

PGY4 - EM - PMAH

Symptomatic bradycardia is defined as a heart rate less than 60/min that elicits signs and symptoms, but the heart rate is typically less than 50/min.

Bradycardia

First-degree atrioventricular block

Second-degree mobitz type i (wenckebach’s) atrioventricular block

Second-degree mobitz type ii atrioventricular block

Third-degree atrioventricular block (complete heart block)

Adult Bradycardia Algoriythm

Indications of emergency pacing :

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Bradycardias :

1. Symptomatic sinus node dysfunction
2. Second- and third-degree heart block
3. Atrial fibrillation with a slow ventricular response With myocardial infarction: new left bundle branch block, bi-fasicular block, alternating bundle branch block.
4. Malfunction of an implanted pacemaker

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Tachycardias :

1. Supraventricular dysrhythmias
2. Ventricular dysrhythmias

Contraindications

No absolute contraindications

Complications

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1. Failure to recognize the presence of underlying treatable ventricular fibrillation
2. Induction of ventricular fibrillation (rare)
3. Soft tissue discomfort

Components of a cardiac pacemaker include:

TECHNIQUE

1. If time and conditions allow, explain the procedure to the patient and administer IV sedation and analgesia before pacing.
2. Vital signs and ECG monitoring are mandatory during the procedure.
3. Place the pacing pads on the patient’s chest either in the anterolateral or anterior-posterior position.

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• In bradyasystolic arrest or with depressed sensorium, turn the stimulating current to maximum output; after restoring pulses, you may titrate energy downward to a level just above loss of capture.

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• In a still-conscious patient with a hemodynamically compromising bradycardia, slowly increase the output from the minimum setting until capture—usually between 50 and 100 mA.
• Continue pacing at about 1.25 times the threshold of initial electrical capture.

4. Assess capture using the ECG on the filtered monitor of the pacing unit.

5. Look for the presence of a consistent ST segment and T wave after each pacer spike.

6. Palpate for carotid and femoral pulses with each such wave- form.

Failure to capture with transcutaneous pacing may be related to

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1. Faulty electrical contact.

2. Inadequate current.

3. Poor pacing pad placement.

4. Underlying pathology.

Thank you