Giotto entered sickbay doing his best impression of someone who wasn't nervous or apprehensive.
The older you got, the more disciplined you became about bringing your body in for maintenance, but the more concerned you got about check-up results. He wasn't worried about general fitness. He could easily keep up with the officers in his command who were half his age (and sometimes leave them winded), but a lifetime in security had left a host of old injuries not mention exposure to a pretty broad array of chemicals, radiation and weird energy fields. Hence the need for physicals, even if the experience was never something to look forward to.
Today in particular it was very unlikely to be a good experience. Coming in now was not just a matter of slightly overdue maintenance. The doctor had reason to be unhappy and even if Giotto did not regret taking the safest option and would do it again, he felt he owed McCoy some sort of apology. Or at least someone to vent at, which was the more likely outcome (on some level Sam couldn't help thinking that placing himself in position to take the doctor's ire was probably what he owed to everyone else).
He sighted the doctor and falling back on habit straightened to something close to attention. "Giotto, reporting for my physical."