Transesophageal echocardiography (TEE or TOE) used to be the domain of cardiologists. It has lately seeped into other areas of medicine where hemodynamic evaluation is crucial. ICU’s and occasionally OR’s use them even for non-cardiac surgery. But the TEE probe can quite easily be used in any unconscious, intubated patient. One obvious indication would be cardiac arrests.
TEE in cardiac arrest
I’ve heard it mentioned before, but I somehow didn’t view it as a practical possibility outside the OR. Not until I listened to Mike Mallin talk on TEE and cardiac arrest at SonoNorway. When people take the extra effort to learn, and then push on to just get out and do it, they not only change their own practice, but can really change other people’s perspective. Like Mike did here. They do TEE in their ER – out in the field(!) It doesn’t sound so crazy once someone tells you they’re already doing it – it breaks down the traditional blocks and fences you got in your mind. It’s always liberating.
Why isn’t TEE used more?
The probes are expensive, and usually hidden in the cardiology or cardiothoracic department. Most sonographers don’t have any training or experience with TEE, so the TEE probe can seem intimidating compared to a standard ultrasound probe. But it doesn’t take that much training. If you know TTE echocardiography, get some training in inserting the TEE probe and obtaining some useful views, you’re on your way. And for basic cardiac function assessment, you don’t even need the ‘proper’ cardiologist’s views. Just like with TTE, any view that lets you eyeball cardiac function will give you clues to the diagnosis. As long as you have some background knowledge on what you’re doing.
Image from Wikipedia under Creative Commons license.
Where’s the evidence?
Not many are doing it, and not many are documenting it. TEE in cardiac arrest makes a lot of sense, and I’ve long been yearning for something more than the generic, algorithmic ACLS approach to cardiac arrest. The algorithm is a good way to get started in the chaotic setting a cardiac arrest initially is, but once you get going, the algorithm feels inadequate. I’ve taken to the advice from Scott Weingart to step it up using art lines and dosing adrenaline after BP response when practical.
TEE takes it a step further: instead of using the surrogate measure of BP, you can evaluate the actual cardiac function. Not just that. With the TEE probe indwelling, you can evaluate the quality of the compressions, and you get minimal hands-off time for evaluating cardiac contractility, cardiac filling and any signs of other pathology like pulmonary embolism, pericardial effusions etc. to sign off your H&T’s.
As mentioned, there isn’t much evidence out there. But in this case that just means we’re at the frontier of cardiac arrest management. There are a few articles on intraoperative cardiac arrest managed with TEE, and describing basic TEE as quite easy to learn and useful in an arrest setting. There’s also an article from the ER setting. So there’s no reason why these findings shouldn’t translate well into medical arrests in ER, on wards or out-of-hospital arrests coming into the ER.
Please let us know if you have other good resources or articles describing TEE in cardiac arrest.
A few articles on TEE and cardiac arrest, most available are from the OR, where the TEE might already be in use, or more readily available, but there’s also an article on TEE for cardiac arrest in the ER:
Training and use of TEE, again, focusing on the OR and ICU, but should be transferrable for ER use as well: