Millions of Americans visit the emergency room once a week - on television, that is. The blockbuster TV hit, "E.R.," very convincingly takes its viewers into the tension and crisis environment of a hospital emergency room. They make you feel like you're there. Of course, they're not the only medical personnel involved in crisis care situation. I was reminded of that the other day on the interstate as this ambulance passed us. Of course, the back has those big red letters - "ambulance." But this particular ambulance had sort of a subtitle - one that raised my eyebrows and made me smile. The whole sign on the back said, "Ambulance - the real emergency room."