hi, im new here and hope someone can help me , recently we had a person with acold m (done by arc) they suggested m neg units, next time pt came back we id the m but was unable to rule out E as we didnt have enough panels. So heres the prob, we have no bb sup. but one tech said we now have to always give this pt E neg units and put it in the pts. history, i have never heard of this and when i talked to the redcross they also said no it is unable to be ruled out as that time.This came to light as the pt came back and we had a total neg screen and panel so we gave the pt mneg units but not E neg and was told that was wrong that once you couldnt rule it out you must always give neg units to the anitibody. we have no sop that says this and i couldnt find a reference in AABB standard. wondering what everyones take on this was.