George, I was in the ICU for about a day and a half but that was because I had begun having problems before surgery with kidney function due to poor blood flow. 24 - 48 hours is not unusual and it doesn't mean that anything is wrong but rather that the team is just watching the patient more closely to insure the best outcome. If there are no additional issues, it can be as little as 4-12 hours. I would suggest that you don't anticipate a time because that builds expectations among friends and family who may think something bad is happening when the only thing taking place is monitoring. I remember almost nothing of the ICU except for a few brief windows each only a few seconds long. I remember just little snippets like: "Larry, Larry, can you open your eyes - the operation went really well and you are in the ICU" and later "I'm going to remove the ventillator tube and I need you to cough can you give me a thumbs up (↑ cough, cough) now just relax."
Larry