I agree Orphan Crow - all doctors take the greatest care with regard to blood loss - hemorrhage is a risk in surgery but one to be avoided at all cost, they don't play fast and loose with your life and blood !
As regards to the OP I am so glad the doctors are aware of this variation in stance, check with the patient and don't just assume because they are a JW and have signed that offensive DPA card (previously called Advance medical directive or no blood form) with the HLC or elders breathing down their necks, doesnt mean they definately dont accept blood in an emergency. Also many cards are found to be out of date, unsigned or unwitnessed which doctors must also be aware of. ( see http://ajwrb.org/medicine/watchtower-no-blood-card )all good news!