My 77-year old father underwent surgery two years ago and I recall how frightening it was for him, my mother, and our entire family. Unfortunately, our fear was realized when he had a terrible post-operative infection that sent him to the emergency room and on to a follow-up surgery.
Sadly, he and my mom were not given good hospital discharge instructions and they ignored signs of problems far too long. No follow-up appointment with his primary care provider had been set, either, which could have averted the complication (and to this day, I kick myself for not catching that).
It could have been much worse. For patients older than my father with more chronic conditions, even surgery that is technically perfect can be fraught with danger and poor outcomes without the application of geriatric best practices that address the whole-person needs of the patient.