I my old place (oh how I miss it ) there was a team of 6 DBAs taking responsibility for all the databases (but the more important tended to be looked after my the people with the most experience) - on call was a weekly rotation and escalation was to the lead DBA (after all he did get paid more )

Here it is just me looking after everything so I have to wear my underpants on the outside of my trousers and be a general DBA superhero whenever the need arises, which thankfully isn't that often.