ALB and chronic obstructive pulmonary disease: In recent years, the predictive effect of serum markers on the prognosis of ICU patients is a major research hotspot, such as red blood cell distribution width to albumin ratio(RAR), lactate/albumin ratio (LAR), creatinine to albumin ratio (CAR), glucose to lymphocyte ratio (GLR) on the prognosis of AP, and the predictive effects of BAR on the prognosis of patients with sepsis, chronic obstructive pulmonary disease (COPD), and post-cardiac surgery [13–16].