As someone else said, these type of COPD patients who come in needing Bipap can go bad very quickly. From what I'm seeing of the situation, you did nothing wrong. Actually, I would say you did more than most ER nurses who are rushed to get back by staying with the patient until the sats came up. No offense to ER nurses, but you know when they bring you a patient as the recieving nurse, it is your job to get in that room, assume care of the patient and let them get back to the ER. It's not your fault that nurse didn't come in the room when the patient rolled in the room.
Bottom line in my hospital, we'll try a labored COPDer on bipap first, hoping to not have to intubate them, but sometimes you do intubate no matter what. I think from what you've described, this patient may have been one who got intubated regardless of what happened. If he was labored and only able to answer yes/no questions, the pressure of the bipap is probably not gonna be enough to carry him through. One question though, I'm assuming respiratory got some gases on him. What did those look like? We usually get an ABG when they come in, they get one an hour or two after on bipap to see if the bipap is effective.
If you got the ABG results after he had been on Bipap for sometime, and they were not really improving, then maybe you could've went to the doc with those and asked about the patient getting a unit bed, based on his ABGs, respirations continuing to be labored, decreasing ability to exert himself even answering questions, etc. That way, you have something to go along with your instinct that he's not a stable floor patient.
I woudn't give it another thought, except be more careful when I transfer patients to that floor to yell so everyone can hear me "the new patient is responsive, I'm leaving now"
I think you did a great job, just remember your confidence in your nursing skills is very important. Don't let another nurse make you doubt yourself when you know in your heart you did the right thing by your patient.