I’ll try and answer your questions

So, they induce therapeutic hypothermia in cardiac arrest with ROSC to help preserve brain function and decrease oxygen demand and inflammation by the neural tissues. The old protocol we used was the patient was intubated on the ventilator sedated and chemically paralyzed to reduce oxygen demand. Remember everything at this point is about preservation of tissues. So we would start cooking and after target temp is reached we let the patient stay at that temp 24ish hours. Afterwards we started the warming process. It’s slow because the warming causes potassium to exit the cell and too fast warming can cause arrhythmias. Once the patient is warmed they assess neurological function (follows commands, brain stem reflexes, ect)

A medically induced coma requires a breathing tube, ventilator, and medications for sedation because a ET tube (tube down the windpipe) is stimulating to the majority of people. After a deemed amount of time the sedation is shut off and the assess the patients neurological function. If they can breath on their own with minimal machine assistance generally they can protect their own airway and the tube can be removed. If the sedation is shut off and the patient does nothing (follows commands, take a deep breath) then the tube stays in place. This typical will be in for 2 weeks before they talk about doing a tracheostomy.