Hi Tim, welcome to the site. I'm terribly sorry to hear what you're going through.
I just wanted to say that I feel for you. Because while you're on one side of the spectrum I'm on the other. You are the parent protecting, watching, and looking down on your child, while I have been the child hooked up to the machines and looking up at the worried faces of my parents as my body failed me.
I realize the situations are different however I still feel that kindred bond.
As a child who's put my parents through more stress than I ever had the right to I'd just like to say a few things to you that may be of comfort. For one. Thank you for always being there. You may not not feel like you've done anything worthwhile for gratitude, but you being there means a lot. In a world filled with medical professionals, needles, the smell of antiseptic, and the white walls of hospitals there is NOTHING like seeing the face of your father or mother.
The familiarity of a lullaby, a smile, a joke, a laugh, a secret handshake, a sing along or a prized stuffed animal are the things that stand out in my mind. I have an accumulation of months missing in my memory. But even though I can't remember I know for a fact my parents were there.
We may not seem like we notice or appreciate it... be we notice and count on it. Just seeing you and having you nearby is enough. It's all a child could ever ask for. In the end that's all we want. The comfort of your presence.
In my case I couldn't be touched. Physically being touched was an unbearable pain so it was avoided at all costs. I'm not sure how it is with your son, but please if he's capable... hug him whenever you can. That's something I lost out on. Because of years of treatments I've learned to associate any kind of physical touch with pain and terrible memories. When someone goes to shake my hand I have visions of having my hand checked for veins for an IV to be put in. Being hugged puts me on edge, because I expect pain. All I have are memories of medical examinations and needles when it comes to physical contact.
So hug him. Hug him like your life depends on it. Make those beautiful memories for him. Make it so that touch it good, comforting, and something to be craved.
The other day I was in line at the grocery store and heard a loud beep that reminded me of the hospital monitors. The panic that overcame me from a simple cash register beep was unbearable.
I have those kind of triggers as well. The distinctive smell of hospital, certain exam rooms, seeing people in scrubs, and so many more.... it's understandable and I feel for you. It's damn hard to deal with. It gets easier when you learn what your triggers are. When I have a doctors appointment I prepare myself. I know the bright neon examination lights will be over head, I prepare myself for them. That way the trigger doesn't pop up on me unawares and set me off into a frenzy.
Again, I'm so sorry you have to go through with this. Just keep in mind that as much as you want your children healthy and happy, your children want YOU healthy and happy. That worry you feel for them, they feel for you as well. Take care of yourself.