Multicenter experience using a new prototype transnasal transesophageal echocardiographic probe

Transesophageal echocardiography (TEE) Is frequently used in the cardiac assessment of critically-ill patients. However, awake or mildly sedated patients are often intolerant to insertion and prolonged esophageal intubation using conventional TEE probes. In addition, TEE probe insertion may be difficult in mechanically ventilated patients. To circumvent these limitations, a prototype miniaturized probe small enough to be introduced transnasally has been recently developed. This prototype monoplane probe has 32 elements, imaging head of 7.3 × 6.0 mm, and shaft diameter of 6 mm. This study describes the combined experience of 5 sites which have used this probe during the past year. After each study. a standardized registry form with information on: (1) clinical indications and settings, (2) feasibility, (3) tolerance, (4) safety of transnasal and oral intubation, and (5) duration of intubation was completed. Results. 196 intubations were performed in 186 patients (age 58±18). 70% of the intubations were nasal and 30% oral. Patients who underwent nasal intubation were anesthesized with topical lidocaine. A prototype nasal trumpet was used to facilitate nasal intubation In 72% of the patients. 47% of the studies were performed in the ICU setting and 43% of these patients were mechanically ventilated. The probe was used as an adjunct to a PA catheter in 27% of the cases. Transnasal and oral intubations were successful in 87% and 100% of attempts, respectively. Of the failed transnasal intubations. 43% were due inability to advance the probe through the nasal passage. The average intubation duration was 63±84 min. (range 5-240 min.). 41 patients were studied for 1 hour or more. Patient tolerance was rated as good or acceptable in 96% of cases. Minor epistaxis was noted in 12% of nasal intubations. Images were rated as clinically useful 97% of the time. Conclusions. Transnasal intubation with the aid of a trumpet is feasible, safe and well tolerated. The new transnasal TEE probe provides images of diagnostic quality, suitable for long term monitoring of cardiac function in the intensive care setting.