Hi welcome to HCM.. Here your mother having swelling of legs and feet after blood transfusion... So there might be two reasons for swelling here after transfusion.... 1.Fluid overload 2.Allergic reaction to blood constituents If allergic reaction suspected in which skin rash can also be there than antihistaminic drug given. .. Meanwhile if leukemic infiltration to kidney present than also edema can be there ... RFT like serum creatinine , blood urea estimation etc done .... You have to maintain blood sugar level within limit by using antidiabetic drug or insulin whichever is needed. And I also want to know which leukemia is there for giving comment for prognosis. .. If leg edema more furosemide like diuretic drug can be given to relieve it ... Low salt diet taken. ... Consult physician with keeping this in mind ... Take care ....