Re: unresponsive patient
I would assume that they wish to have a code blue called just in case of code (best to have equipment and staff on the way to save seconds where seconds count). However, you do not jump into anything untill assessment is done...remember your ABC's of CPR...the assessment of Airway, Breathing, and Cardiac before anything.
Now, as far as doing CPR...a nurse has the clinical judgement call to start CPR and get 9-11 activated so they may hand over care when paramedics arrive.
They do not have a Dx of death per say...however we can say "severe failure to thrive..and describe symptoms like no pulse, no bp, no respirations, nonresponsive...etc." to an MD once the patient has passed...this is normally done with a call to the coroner who needs to be notified asap at time of death. This is certainly in a nurses best interest (or CNA) because the more time that passes makes things seem a bit funny to the family and coroner. So call when you suspect death, and what I usually did was have CNA's continue CPR efforts (what we called a 'slow code' nothing too serious, just going through the motions of compressions/breathing but not to hard as to break ribs or what not) and I would call the coroner and ask to stop CPR efforts according to my assessment data.
Now remember, CPR on a DNR is not to be done if they are dead..and only dead...I mean not breathing AND no pulse! If an unreponsive patient is breathing or has even a slight pulse..you continue CPR. DNR is do not treat...it is do not bring back from death.
And one more thingie here that is good to remember from time to time...remember the cases where someone can be unreponsive and not need compressions or rescue breathing...seizures (or post...just maintain airway or breath dependant), some TIA's, blocked airway, fainting, etc.....

Makes assessment seem pretty important huh...
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