Floyd complained that he could not breath before he was put on the ground. His ability to complain that he could not breath when he was on the ground demonstrates that he was breathing. If your air supply is cut off, you cannot talk.
One of the side effects of fentanyl is that with the right dose, it will lead to slow and shallow breathing...meaning your lungs aren’t getting enough air to sustain the body. You can have some guy dose up, and just sitting in a rocking chair...he’ll run out of oxygen eventually, and die right there...on his own.
If you aren’t in fit condition (one of Floyd’s problems) and an a heavy smoker (which Floyd was)...you probably won’t live too long.
If your air supply is cut off, you cannot talk.
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That is not true. Basic restraint 101. People with compromised breathing still can talk. There is a lot of residual air in lungs when breathing normally. That gets used until no air and rapid death