His sat's are down to 100%, Get a tube!

We got a call for an elderly male with difficulty breathing. Got to scene, and when walking in the door you could see the man was working to breath. We approached him, first responders had a set of vitals and let us know lung sounds were diminished in all fields. He was satting at 94% on room air, so we put him on O2, brought him right up to 100%. The patient had a history of pneumonia and had been released from the hospital three weeks prior. En-route he got a combi-vent, patient was on albuterol at home. This really didn't touch him at all. EKG showed A-Fib, but patient had a history of this. Sats stayed at 100% the entire ride, he would cough from time to time but it wasn't productive. We got to the hospital, gave our report, and by the time we left the guy was RSI'd and tubed. And...I don't get it.

I understand that I'm just a student and I certainly don't know everything there is to know. It just seems to me, that if the patient was moving air, and a mask would bring him to 100% that he wouldn't need the tube. Patient had good cap refill, and ETCO2 was within normal limits. Maybe I just don't know enough, but it seems to me that you shouldn't want to tube someone unless absolutely nessecary. With the tube you generally buy them more meds, a longer hospital stay, and an increased risk of certain conditions. Here's my theory on things. I look at it as working my way up. Start with a nasal canula, if it's obvious that won't work, move on to a NRB. If the NRB isn't doing the trick, move on to bagging the patient. If bagging alone isn't cutting it, it's time to buy a tube. Maybe that's overly simplistic. I don't know. But what I really don't know is why this guy bought a tube. If you have any ideas, I'm totally open to hearing them.