Preventing Contamination During Transesophageal Echocardiography in the Face of the COVID-19 Pandemic.

To the Editor:

As the world sees an exponential rise in cases of Coronavirus disease (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), we are continually innovating and developing new ways to prevent exposure as well as contamination of healthcare providers. The American Society of Echocardiography recently developed guidelines for safely performing echocardiography on patients suspected of having or are positive for COVID-19. The guidelines speak on “who to image,” “where to image,” and “how to image,” with the goal of protecting the physician performing the transesophageal echocardiogram (TEE) or transthoracic echocardiogram and the sonographer assisting during these cases.

As a perioperative echocardiographer, I have come to realize that the risk of aerosolization is highest during intubation of the TEE probe, if the patient coughs, and when the provider manipulates the probe to obtain images. During perioperative cardiac cases, with patients already intubated and connected to the ventilator; multiple manipulations of the TEE probe lead to contamination of oral secretions from the probe to the TEE and anesthesia machines as well as other areas where a perioperative physician is providing care. Birnbach et al. demonstrated how rapidly an anesthesia provider's hands could contaminate any surface that he or she touches after endotracheal intubation.

To minimize this contamination, I propose the following novel method to safeguard healthcare providers and perform TEE safely. You would need an ultrasound (US) probe cover, bite block, and clear plastic equipment cover.

The steps are as follows:

Wear proper personal protective equipment as per the recommendation of the American Society of Echocardiography Statement on personal protection during care for COVID-19 patients. I recommend double gloving as a standard irrespective of the level of precaution.

Insert the TEE probe through the bite block and have it ready (Fig 1 , A).

Fig. 1

A - TEE probe with bite block pre-inserted, B – Insert TEE probe in the designated space in the middle of US probe, C & D- TEE probe tip coming out from tip of US probe cover after making a hole.

Open the US probe cover and insert the TEE probe with the bite block where the US probe typically is inserted. Make sure the tip is positioned in the middle of the US sleeve so that there is no redundant probe cover (Fig 1, B and C).

Make a hole at the tip of the sleeve so that only the TEE probe can come out (Fig 1, D).

Cover the whole probe, including the control knobs, with the probe cover and secure with plastic or paper tape around the controls (Fig 2 , A and B).

Fig. 2

A- TEE probe coming out with bite-block inside the US prober cover. B- US probe cover covering the whole probe including controls except the part inserted in patient. C- Bite block as inserted inside the probe cover. D – Final setup in clinical use.

Insert the TEE probe without the plastic sleeve in the patient's esophagus.

Remove the soiled outer gloves and insert the bite block, which is inside the US probe cover in between the patient's teeth (Fig 2, C).

Remove the second pair of gloves and sanitize hands. Wear a fresh pair of gloves.

Perform the TEE in the usual fashion except that the TEE probe only will be manipulated from outside the cover (Fig 2, D).

Once the procedure is done, the US probe can be extubated safely and pulled back into the US probe cover.

After the probe is extubated, place the entire probe in a disinfectant bag or container to be sterilized using appropriate protocols.

In my experience, a complete TEE examination can be performed in this way without any difficulty or compromise of the image quality. Since the TEE probe is being manipulated inside the US sleeve, there is no contamination of the US machine or other anesthesia workstations. Nevertheless, it would be prudent to perform frequent hand hygiene and appropriate use of personal protective equipment as per the nature of exposure. I hope this technique will be helpful not only to many perioperative physicians involved in echocardiography but also to physicians performing TEE elsewhere in the hospital.

Conflict of Interest

None.