In this retrospective study, our data showed that pneumonia with a lower oxygenation index was associated with gender, DM, APACHE II score, LIS, SOFA, NUTRIC score, PH value, lactic acid, WBC, neutrophils, lymphocyte, neutrophils/lymphocyte count, creatinine, D-dimer, PCT, CRP, RAGE, and albumin levels. Here, CRP is linked to susceptibility to pneumonia measurement.