Hi Laura,
I'm so sorry to hear about Jim's set-back.
As others have already told you, this bump in the road to recovery is not unique and it is usually well handled by the skilled and caring staff at hospitals as good as the one that your Dad is in right now. However, it's frustrating for the patient and scary as heck for those who want to see him return to his usual self with little pain or suffering.
My advise is to just try to comfort Dad when you are with him and encourage him to keep trying. Keep telling him you know he will be able to do the breathing and whatever else the staff expects from him. If not right now, then very soon. Don't get discouraged and don't let him be too discouraged.
I'll be sure to say a special prayer for him in church tomorrow and I'm sure many others here will keep your family in their prayers too.
I hope to be hearing much more positive things from you in the next couple of days.
Ron K