Thing to watch out for with rapid dosing of Fentanyl is chest wall rigidity, requiring positive pressure ventilation, either this breaks it or the resulting hypoxia does. A rare but potential problem may occur with the rigidity is the need for chemical paralysis with succinylcholine in order to ventilate.
Have only seen it one time on my cousin, he turned absolutely purple. Don't know his sat at the time because he was bundled up going to CT scan, the RN rushed in and IV pushed the fentanyl and he locked up. Luckily it passed after about a minute.
While your MD may not utilize anesthesia, perhaps you should find one that does and then you will be introduced to propofol and the wonderful characteristics of this drug, especially the benefits of it for outpatient diagnostic procedures. WARNING: while some GI docs and staff RNs are going toward the trend of letting staff RNs push propofol, I would strongly urge against this. Propofol is a general anesthetic and should be treated as such. This has been discussed elsewhere in the GI thread.
I feel your pain about being awake. I have had my esophagus dilated several times under CS. I only remember going for the tube one time. Think one hand was on the tube and the other hand was on the doc. Not good. The last time I was given nothing but a can of lidocaine and was dilated with the bougies and the butthole doc saying "take a deep breath 'cause you won't be able to breathe on these last two". That is the last time that will ever happen. I don't know who had more KY on them, he or I. I emptied the can of lido on the back of my throat, I'm surprised that I didn't go into methemoglobinemia...
Let us know how it goes. Stick with fentanyl. Demerol is for the birds. If they don't listen to you about not wanting demerol:
1. pick another doc (pref one that uses anesthesia services)
2. you could always tell them you take a MAOI (contraindication to demerol usage).....but that would be lying and on your medical record then so take that with a grain of salt...#2 is a joke by the way..