Transcutaneous cardiac pacing is a temporary method of pacing that may be indicated in patients with severe symptomatic or hemodynamically unstable bradyarrhythmias. It is particularly helpful in patients with reversible or transient conditions, such as digoxin toxicity and atrioventricular block in the setting of inferior wall myocardial infarction, or when transvenous pacing is not immediately available or carries a high risk of complications. Most patients with minimal hemodynamic compromise require a current of 40 to 80 mA; pacing thresholds tend to be higher in patients who have emphysema or pericardial effusion and in those who receive positive pressure ventilation. On electrocardiography, successful capture usually is characterized by a widened QRS complex, followed by a distinct ST segment and broad T wave. The hemodynamic response to pacing also must be confirmed by assessing the patient's arterial pulse. Proper skin preparation and electrode positioning ensure successful capture in most situations. Adequate sedation and analgesia are essential in ensuring patient comfort.
