As someone who has been shocked by the ICD, lying on the floor seems like a bad place for it, since the floor is a hard surface. You're gonna jolt and spaz and scream. According to my GF, the screams are quite terrifying. One of the orderlies or admissions people (I cannot remember which) at the ER laughed once when it happened to me. I don't think he was being a douche; more likely it was the whole unintentionally laughing at inappropriate times thing that happens to a lot of us, including me. Once the shocking started, the first thing I would do is lie back in my recliner in case there were more. Surprisingly, I don't think I've ever been shocked while vertical. It's always been in the chair, bed at home, hospital bed, or stretcher. I have no explanation for that; maybe a medical nerd knows if there are reasons why you're less likely to be shocked while vertical, or if I've just managed to beat the odds on that one.