Fun fact: people are often hesitant or uncomfortable to do effective AED and CPR on peeps with breasts because they either weren't taught about it or are too embarrassed. Get out my tits if I'm buying the farm. I'd rather my girls get exposed than fucking die.
For the curious: It's ok if you end up touching breast tissue when performing CPR. It happens, especially for those with large breasts.
When using an AED you need to expose the chest and remove/cut off the bra to get the pads placed correctly, to avoid arcing with an underwire, and to get gel on the skin under the pads.