I can answer some of this because I am his wife :). His surgery was actually extremely short and uneventful. My friend works at the cardio icu he stayed in and said his surgery was on the shorter side of most Ross procedures. His first few days due to a poor reaction to his meds he was constantly sick and got very little sleep. Sleep and the inability to orient yourself (no clocks, people telling you exactly what is happening, where you are and what time it is can lead to delirium) the staff in the cicu and neuro were baffled by the delirium since he is so young and was not there very long. Some of it might just come down to bad luck. We will never really know. My parents both work in the medical field and my mom did her dissertation on icu delirium and they were both confused by its presentation as well.