So today I finally got my blood work done. It turns out that you just need to meet a nice doctor. That jerk I saw last time that refused to give me a blood test should get his license revoked if my blood test reveals anything bad! *HMPH* Anyway, it was quite fascinating how the simple syringe technology has matured over the past years ( since it's been a while since I had any blood drawn ). Well, I wouldn't call it an advancement in technology since the fundamental mechanism by which the transfer of blood is made is still the same, it's just the way in which it is carried out is different. It turns out that in studies they discovered that drawing blood the old fashioned way had potentially serious hazards, so hostpitals started to adopt new types of syringes that draw blood directly into the vacuum container tube. My only question is whether there is any way in which the pressure is controlled or is it simply assuming that the pressure will quickly stablize between the two medium and that it is done at a rate that human being won't feel it in a painful way. I'd be interested in finding out as my physics is kinda rusty. I'd imagine that this kind of blood drawing would be bad for small vessels that can easily collapse with a sudden void of blood. Any experts around?