Its funny that you ask that question because i was in the hospital a few months back for a few days and they put these really uncomfortable inflating air bags on my legs. i asked the nurse why i had to have them and she told me to prevent blood clots and i asked her the same thing you just asked. Why dont i need them at home to sleep, and you know what she said? She said--- Thats a good question ill have to ask the Dr. She did ask a Dr and he told her when you sleep you toss and turn your body dont stay in one position all night but being confined to a bed you need the bags to help out, sitting is even worse than laying because your puting more pressure in one direct area pinching the blood flow off even more.

As a nurse she should have been able to tell you that , I'm a nurse too and have also been a patient with scd's, or sequential compression devices, after breaking my neck ten years ago. I guess all we need is some of those set up in front of our TVs :) but yeah, they constantly massage your legs to pump the blood up toward your heart since you aren't walking around as much in the hospital, normally your muscles do this massaging for you just by walking. Sorry for the lengthy reply, but I thought it might be interesting to know

Well i look at it this way, if a Dr gotta run out and get on a computer to tell me whats wrong with me then i can cut her a break for not fully knowing why we dont need compression bags at home to sleep every night, you nurses do all the real work these days ,Drs want to give ya pills and a bill

Well then my wife is never getting a clot! She sleeps like a wolverine on adderall. lol. Makes sense though. Hope you are feeling better.