A Delta Check Was Noted for Potassium After a Surgical

A delta check was noted for potassium after a surgical patient was transfused with 2 units of packed red blood cells. The pre-transfusion potassium was 3.1 mmol/L and the post-transfusion specimen was 6.2 mmol/L. What could be the reason for this sudden increase?

A) Coagulation factors were diluted out of patient plasma.
B) Red blood cells were washed prior to infusion.
C) Red blood cells spent maximum time in storage.
D) None of the above