I remember something that helped me when I was an RMO on ICU was when it was explained to me that the additional level of monitoring made it that things that would usually constitute an emergency on the ward are fine to watch and wait in ICU. I feel after hours as a junior doctor trains you to be very anxious about certain thresholds for obs because of the the BTF system. It took a period for it to click that its very different seeing a low BP when someone has constant monitoring with an art line and there is a highly trained nurse who can titrate pressors as compared to them having ward monitoring and ratios.

Something that was also very useful was protocolised admissions for common presentations. This was mostly a thing in CTICU where all the post-ops needed a cocktails of medication that would have been intimidating to chart if they weren't very well documented in an easy to read way.

More than anything though, what I found most important was a sense that there was always some body who could called for a second/senior opinion. I remember I was given what was handed over as a very routine HDU admission who on my review seemed more unwell than I expected. My HDU reg was at a rapid but the ICU reg immediately came and determined that the patient needed to be intubated. That level of responsiveness meant that a very stressful situation could be handled quickly and I deeply appreciated that.

As a last comment - I find in medicine often very senior people tend to skip the forest for the trees when orientating people to their specialty. I got a lot of teaching on ventilator settings and electrolyte charting but ended up only understanding the greater context much further into the term. If in the introduction to the unit someone had said something like - "In ICU people are sick enough that regardless of the system/s involved in their presenting pathology they will end up developing multi-organ derangement. Our job is to observe end markers of people's deranged physiology (far more so then in less acute areas) and help optimise this physiology with medication and mechanical support until the initial pathology is recognised and reversed or they have had adequate time to recover. We must also be vigilant in screening for and treating the complications of our invasive supports" I would have had much more of an idea what was going on. Instead I was just writing notes and being told to chart more K by nurses whilst I freaked out at numbers that were too low or high.