parent very critically ill

hi,sorry if i babble but my dad who is 83 is critically ill.He had a triple heart bypass on monday and he had a bleed after it which meant more surgery to repair and now he is classed as very critical and the sickest person in the hospital.He's my dad i am 60 and i am heart broken,i have taken my mum a few times to sit with him she is poor mum in total shock he only went in for stents but needed a bypass,he has not been woken up,he's on bypass machine and his organs are getting weaker,we have been told that there is more chance he won't make it than will and i selfishly cannot take this i want my dad,the days before the op i had endless messages and calls from him,we were'nt allowed to visit because of covid he cried lots every day to me and my mum,told me to look after mum told us he loved us etc,nobody expected this to happen and i am really stuck ,i ring the hospital for updates but they say he's on a knifes edge could go at any point so just waiting for that call.So reason for a posting is please can anyone offer any advice.thank you