If you believe in God and know that the next moment saved person dies is heavenly life it is not a big issue .
There were many other reasons many died for the faith they professed .
Harold Camping spoke about people who died in earthquake in Haiti this year. For those who believed in God truly and died it was a blessing from God ! As they left the misery they had in their country and now went to heaven to be with Christ in their soul existence.
You can assume that some who died for refusing the blood transfusion faced an accident beyond his or her control and had to forfeit his or her life !
Or better died for his conviction like many christians that died before.
There is a river between the two lives .One is on left side and you are there and have a child that faces death .If you love God and your child, you will do the best for your child . And will refuse the blood transfusion and let your child go to the other side of the river where there is a better life : heavenly life .And you know also that most children that grow further in this life on this side of the river don't believe in God at all or believe wrongly and may never be saved .Which is the better solution to keep your child forever ?