Yeah-- If I were unconscious, our dogs would simply sit next to me, possibly drooling onto my face, and wonder when I was going to wake up and feed them.
LOL, I hear you! But listen to this: my mom and dad were visiting my sister a few weeks ago and even though their pets (cat and dog) had never paid much attention to my mom, during this visit they never left her alone. They sat on her lap, circled her feet, smelled her face, and watched her constantly (she wasn't feeling well, but chalked it up to the fatigue of travel). The day after they returned home, she collapsed and was hospitalized for a week. Don't tell me that pets can't tell when you're really sick.
Sometimes I think that a "Lab" report (from a real Lab!) and a "Cat" scan are some of the most valuable tools you can have in your diagnostic arsenal.