Update

Clearance for surgery - check
Childcare arranged - check
Bag packed - check
days to go - 4
freaking out - in progress...

I can only relate this to childbirth, as it's the only other major medical event I've experienced:

There was lots of fun had, which got me in this state - conception
There have been months of work, planning, and preparation for this event, while getting fatter and fatter - gestation
There have been myriad invasive medical tests and procedures - the many doctor visits
There will be a short, painful stay in the hospital, where I will enjoy lots of pharmaceutical pain relief while I am relieved of my burden - childbirth
There will be an acclimation period, where the small new being will only consume liquids and soft foods and will require constant care and monitoring - infancy

So, 'scuse me while I break out my blankie and teddy bear, while I freak out for 4 more days.