12. Complicated with severe heart disease (NYHA classification >3), renal insufficiency (serum creatinine > 442μmol/L or receiving renal replacement therapy), severe hepatic disease (Child-Pugh classification = C), diabetes (fasting blood glucose not in the range of 6.7-10 mmol/L ), anemia (Hb < 90g/L even after blood transfusions), or acute infectious diseases (WBC>10000/μL) before surgery.