Those of us who have gone through this know exactly how you feel - the dread, the guilt, the anguish, the questions, the frustration, the tears, I'm afraid it's what you have to go through in order to help Max. He will probably get better about coping with the procedure in time and he will learn to separate the times when you have to give him fluids from the rest of his time with you. You will learn how best to handle him, and it will become a routine - not one you look forward to, but one that is part of your day. These early days are the worst time, except the much later time when your CRF cat gets so thin that you can barely get a needle in - then you wish he was bucking and writhing again.
I give fluids alone also, and I also kneel down with the cat between my knees. I've had cats that have bucked and writhed so frantically that the needle has come out and I had to learn to keep a few extra by me on the floor so I could put on a new one and start again. My cats have slashed, snarled, thrown themselves on their sides and backs, whirled like dervishes. Sometimes I've had to scruff them and hold up the pocket of skin in the same hand then push in the needle with the other, then grip their shoulders hard with my knees. I think I've had only one cat that simply lay there and that was a foster who was in late stage CRF.
Give both of you a treat after each treatment, that's what I do. A relaxing video, cup of tea and chocolate biscuit for me, and a cuddle session for them.
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