I believe the same thing happened to my Dad. I saw him in the hospital the night before he died, and while somewhat out of it, he could talk and sit up. The next day when the morphine drip started he first went into a coma, then hours later started gasping for air (his neck and chest would lift off the bed as if he was suffocating)
And what you have described is NOT from the morphine but rather from the death process. As with the originator my question to you is what was the underlying disease from which you father suffered?
its the absolute duty of the medical profession to relieve pain....there are consequences for sure....death for instance...
doctors can't win...they can be sued for not managing pain and they can be sued for prescribing too many pain meds....
if your father had a morphine drip he had to have signed a paper that he knew what it was...at least in my neck of the woods....