Can this be malpractice or wrongful death?

my husband had surgery and for a year had infections because of the surgery, he passed away several months ago . he was brought to the hospital 5 days before he died and the dr was told by both me and my hiusband that they should take blood cultures but they ignored us and sent him home after getting pain killers and said it was siatica. his white blood cell count went from 6.8 to 9600 within 7 hours ( he went to the er twice in one day). he also was on dialysis and had missed a day because of the pain . we went to the hospital in the next city where they admitted him, did the cultures(which were positive) and he also had to hae surgery because the infection had gone on too long. i got a call from the doctor the next day apologizing because they neer saw it coming. thanks