This is really rough news. I can empathise completely with this, because some years ago my wife was having a major operation when she suddenly suffered a critical reaction to the anaesthetic, and technically died on the table before they managed to get her back. I only found out when I arrived as normal in the evening to see her after the op, and was ushered into a side room. She was on ICU, and I was told 'the next 12 hours are crucial', and warned that if she survived then brain damage and kidney failure were the next two hurdles. Never known a night like that one. They sent me home, but I was on the phone to them every half hour.
She was in hospital for three months, but eventually recovered. It left her disabled, unable to drive, on morphine for life and increasingly wheelchair-bound, and with vascular disease, but I'm still grateful every single day.
My thoughts completely go out to Roydo. Truthfully, until you go through something like that you just don't know, you can't imagine...