NPPB and diabetes mellitus: Potential variables for this model included gender, age, body mass index, surgery time, serum creatinine, eGFR, hemoglobin, hemoglobin A1c, left ventricular ejection fraction rate, fasting plasma glucose levels, brain natriuretic peptide level, percentage of hypertension, the incidence of having diabetes mellitus, and percentage of patients taking diuretics.