Ah, OK. I believe the proceedure you're having is called a peripheral blood stem cell harvest. This approach differs from bone marrow transplant.
Those shots/injections previous to having the proceedure are to boost your white blood cell count. In doing so, this forces stem cells out of the marrow into the blood. So basically you'll have two IV needles, one in each arm. The blood comes out of one arm, goes into a device that seperates the stem cells from the rest of the blood (harvests), and then goes back into your other arm.
It's really a much safer proceedure as there is no anesthetic required and it's no where near as invasive as poking mutiple holes into your plevic region.
You might want to find out how many stem cells they plan to harvest. If the guy you're donating them to is a big person, it will probably be in excess of 5 million/Kg.