What to do?

Knock gently on the door, come easy to  edge of the bed, lean near, address by first name, share yours and  why you are there. If you are not known tell how you happen to come. 
I often say, "I am a little afraid to be here, but I wanted to be here no matter what". 
Be there with great respect of the person you know to be there inside.  Look around the room, are there flowers to be freshened, comfortable lighting vs a glaring over head light?. Is there a chair you can easily move to be adjacent to the bedside? If not perhaps request one from the staff. It is important you be comfortable to have a comfortable "conversation".  
Sometimes I sit on the arm rest to be just about the right height to be in a relatively normal position for interchange

• Look for subtle clues of body language to judge how the person is responding to your touch or words, such as change in breathing rate, a sigh, slight wincing of a small muscle, adjustment of fingers, fluttering of eye lashes, squeezing lids of eyes. They may give clue on how you are doing. 
• Get comfortable in chair, if you wish to just be near.  Be ready to move chair if nurse comes in and needs access to bed.
• Share approximately how long you will be there. 
• You may want to hum or sing. Be close and with great dearness and sensitivity.
• Play an instrument

Even though this person before you does not look like themselves, know that your parent, child, friend is there inside but perhaps too ill to respond but they will be feel cared about, relieved, feel loved and reassured. Or they feel a need for silence and just a loving silent presence. Elisabeth Kuebler-Ross, MD, the wonderful doctor of the heart on the frontier of changing how we are with the dying, said the greatest gift you can give, is just to be there with the gift of yourself. 
If you want to tidy the room or change things, such as moving a chair, changing the water in the vase of flowers or leaving the room, tell the person, "Your beautiful yellow roses are looking a little droopy, I will add  some fresh water."
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