Make an effort to build alliances with your parent's medical team.  Medical personnel are often overworked and everyone is stressed out, from patients to family members to doctors and nurses.  We found it beneficial to show a little appreciation whenever we could.  When our dad was in the hospital, for example, and we were running out to Starbucks, we would ask the nurses if we could bring them anything back.  They seemed to truly appreciate the gesture.  

And once you’ve created an air of good will and mutual respect, you can defuse a lot of the tense situations that are not uncommon in hospitals.  This relationship (between you and the medical team) also serves to humanize your parent - the team will think, “Hey, this is someone’s dad, not just any old patient.”  And that will make you far more comfortable, knowing your parent is being well cared for, when you are unable to be there yourself.