like.. several?
In 2013 there were 1,923 lung transplants performed in the U.S.
2,192 heart transplants were done in 2006
Animal to animal transplants only ever occur for research purposes, not life-extension of family pets. However when researching for human transplants, many animal transplants have to be done.
2 million
yes many transplants have already been performed
An estimated 50,000 men receive hair transplants each year
something?
depends on the transplant?
Within transplantation surgery, there is nothing to be "sure" about, even when working with allograft transplants. With xenograft transplants (which are exceptionally rarely performed), risks are much higher and there are additional risks which do not occur with allograft transplants. In either case, there is no way to be "sure" of a good outcome, due to the many known and unknown random variables which affect outcomes.
1
No studies have been done
Very few, since the success rate was poor.