Comparison of a transesophageal and precordial ultrasonic Doppler sensor in the detection of venous air embolism.

Early detection and prompt treatment are important factors that limit morbidity and mortality secondary to venous air embolism (VAE) (1). The precordial Doppler ultrasonic sensor and transesophageal echocardiograph are the two most sensitive monitors currently available to detect VAE (2,3). The Aloka SSD-870 transesophageal echocardiograph is equipped with a Doppler sensor at the distal end of the probe, thereby providing Doppler ultrasound monitoring for VAE in addition to visual monitoring for VAE with echocardiography. Potential advantages in the use of the transesophageal sensor as opposed to a precordial Doppler sensor for monitoring of VAE are the following: (a) one is able to confirm the area within the heart that is being monitored by Doppler ultrasound; and (b) the quality of the Doppler signal is independent of external body habitus with the transesophageal Doppler sensor, in contrast to the precordial Doppler with which signal quality is very dependent on external body habitus (4). The purpose of our study was to compare the sensitivity of the precordial Doppler with the transesophageal Doppler sensor in detection of VAE.