Abstract: Objective To explore the value of pulmonary CT combined with neutrophil to lymphocyte ratio (NLR) and albumin (ALB) in predicting the clinical prognosis of the elderly patients with chronic obstructive pulmonary disease (COPD) combined with type Ⅱ respiratory failure. Methods A total of 108 COPD patients combined with type Ⅱ respiratory failure diagnosed in our hospital from December 2019 to December 2021 were enrolled and followed up for 3 months. According to the prognosis, the patients were divided into the survival group (97 cases) and the death group (11 cases). Lung CT was performed in all patients to determine the maximum abnormal end-inspiratory volume (Vcin)and the maximum abnormal end-expiratory volume(Cvex), and the level of NLR and serum ALB were collected and compared in the two groups. The value of Vcin, Cvex combined with NLR and ALB in predicting the prognosis of COPD patients with type Ⅱ respiratory failure was analyzed. Results The Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score and the levels of arterial carbon dioxide partial pressure(PaCO₂), Vcin, Cvex and NLR in the survival group were significantly lower and the level of ALB was significantly higher than those in the death group (P<0.05). ROC curve showed that the area under curve (AUC) of Vcin and Cvex for predicting the clinical prognosis of COPD patients combined with type Ⅱ respiratory failure was 0.69 and 0.65, and the sensitivity and specificity were 72.56%, 66.74% and 66.43%, 62.59%, respectively; And the AUC of NLR and ALB for predicting the clinical prognosis were 0.68, 0.67, the sensitivity and specificity were 64.58%, 63.67% and 61.37%, 62.54%, respectively. The AUC of Vcin, Cvex combined with NLR and ALB for predicting the clinical prognosis was 0.81, and the sensitivity and specificity were 85.42% and 81.39%, respectively. Conclusions The sensitivity and specificity of lung CT combined with NLR and ALB in predicting the clinical prognosis of elderly COPD patients with type Ⅱ respiratory failure are more than 80%, which has high application value for clinical evaluation of the prognosis.

Key words: lung computed tomography, neutrophil to lymphocyte ratio, albumin, chronic obstructive pulmonary disease, type Ⅱ respiratory failure