Initial Experience with a Disposable Transesophageal Echocardiography Monitoring System during Therapeutic Hypothermia following out of Hospital Cardiac Arrest

Abstract

Objective: This investigation summarizes the initial clinical experience of trained echocardiographers who utilized a miniaturized disposable monoplane transesophageal echocardiography (TEE) system in patients undergoing therapeutic hypothermia following out of hospital cardiac arrest.Design: A retrospective, single-center, observational study. Setting: A tertiary care university hospital.Patients: We retrospectively reviewed the medical records of 13 consecutive patients undergoing therapeutic hypothermia following out of hospital cardiac arrest in which a disposable monoplane TEE probe was placed to observe myocardial recovery and potentially guide hemodynamic optimization. Measurements and Main Results: A total of 40 imaging sessions were performed. The success rate for obtaining the mid-esophageal four chamber and the transgastric mid-papillary short axis views were 92.5% and 100% respectively. Endocardial border definition was adequate in 90% of imaging sessions to measure left ventricular end diastolic and systolic areas enabling calculation of fractional area of change. Assessment of right ventricular function was possible in 92.5% of imaging sessions.A significant number of imaging sessions (12/40, 30%) provided information that clarified the patient’s biventricular function in the setting of ambiguous invasive pressure monitoring measurements.Conclusions: Acquisition of a mid esophageal four chamber and transgastric mid papillary view was possible with the miniaturized disposable TEE probe in the vast majority of imaging sessions. This information enabled the qualitative assessment of right ventricular function, measurement of left ventricular end systolic, and diastolic area with a high degree of success in patients during therapeutic hypothermia following cardiac arrest. The authors postulate that serial assessment of biventricular function and filling with serial TEE imaging provides information that cannot be reliably inferred from other advanced hemodynamic monitoring devices in routine clinical practice. This work was funded by the Department of Anesthesiology at Vanderbilt University Medical Center.