Evaluation of transesophageal atrial pacing in the prone and lateral positions.

OBJECTIVE To develop recommendations for positioning the second-generation pacing esophageal stethoscope for transesophageal atrial pacing in patients positioned prone (P), right lateral decubitus (RLD), and left lateral decubitus (LLD). DESIGN Prospective; patients assigned consecutively. SETTING Tertiary and university hospitals. PARTICIPANTS Thirty (10 in each position group) adult patients undergoing surgery. INTERVENTIONS The optimal depths of insertions (DOI) where pacing current threshold was minimal (THmin) were determined first when supine, then after positioning. MEASUREMENTS AND MAIN RESULTS Transesophageal atrial pacing was successful in all patients supine and after positioning. The optimal DOI varied from 2 cm less deep to 4 cm deeper in positioned patients compared with supine patients. Patients positioned P required equal or up to 8 mA greater current outputs to achieve transesophageal atrial pacing; LLD and RLD patients may require up to 8 mA greater or lesser current compared with supine patients. CONCLUSION Transesophageal atrial pacing can be used safely and effectively in patients positioned P, RLD, and LLD. Recommendations are presented for positioning the pacing esophageal stethoscope. Emphasis is given to using the lowest DOIs and smallest currents to reduce the chance of transesophageal ventricular pacing.