There are many ways that TEE can help you in cardiac arrest. One of these is to monitor your chest compressions to make sure they are actually doing what you want. Although this makes sense intuitively and is supported by animal models, there has not been a lot of evidence to date. This article takes a step in that direction by showing some data on outcomes in humans.
https://www.ncbi.nlm.nih.gov/pubmed/30825552
