Hi pattiwagon, I am so very sorry about your dad. I dont have much knowledge regarding this and even trying to do some research on the internet it is difficult to find anything at all. What I do know is that 1 pint of blood is equal to 10% of your body's blood volume. In someone who has a heart condition and known blood loss for whatever reason it would put strain on their heart and make it difficult to breathe. It is amazing to imagine your father with 30% blood volume loss...I would think it would put increased strain on all his organs, brain and make it unable to function. I found this one article that describes blood volumes and such...I dont know if it will be of any help to you at all but I will put the link below anyway. Please do keep us posted on how he is doing and feel free to post as often as you like...we are always here. Take care
http://www.cptips.com/blood.htm