External transcutaneous pacemakers in interhospital transport of cardiac patients.

From October 1985 to April 1988, 297 patients with presumed unstable angina, acute myocardial infarction, or permanent pacemaker failure were transferred by helicopter from community hospitals to our medical center for tertiary care. Fifty-six patients (19%) experienced treatable bradycardia (heart rate of less than 50) and hypotension (systolic pressure of less than 80 mm Hg); nine patients (16%) improved without treatment, 24 (43%) responded to atropine, and 23 (41%) were unresponsive to atropine. An external transcutaneous pacemaker (EXTP) was applied to patients unresponsive to atropine if a transvenous pacemaker could not be placed. In the atropine-unresponsive group, 11 (48%) had a transvenous pacemaker placed successfully, two (9%) had poor transvenous pacemaker capture (followed by EXTP capture), and ten (43%) were treated with EXTP alone. Eleven patients experienced EXTP capture and improved. Six had profound bradycardia and apnea before EXTP application. Of the 297 patients, 23 (8%) required transvenous or external pacing, and 12 of these patients (52%) survived. The availability of external pacing during interhospital transport of high-risk cardiac patients seems necessary for the management of symptomatic bradycardia and hypotension.