Abstract:Objective To explore the risk of malnutrition during invasive mechanical ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and to analyze its affecting factors.Methods A total of 126 AECOPD patients who were admitted to the intensive care unit (ICU) of our hospital from February 2020 to February 2022 and required invasive mechanical ventilation support were selected. According to Nutritional Risk Screening (NRS) 2002, the patients were divided into risk of malnutrition group (86 cases) and non-risk of malnutrition group (40 cases). Clinical data including arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), forced expiratory volume in one second/ forced vital capacity (FEV1/FVC), residual volume (RV), and the levels of albumin (ALB) and prealbumin (PA) were collected. Factors affecting the risk of malnutrition in AECOPD patients undergoing invasive mechanical ventilation were analyzed by multivariable Logistic regression. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive value of the above indicators for risk of malnutrition in patients with AECOPD undergoing invasive mechanical ventilation.Results The proportions of PaO2 < 60 mmHg, PaCO2 ≥ 50 mmHg, FEV1/FVC < 50%, ALB < 30.00 g/L and PA < 145.00 g/L in the risk of malnutrition group were higher than those in the non-risk of malnutrition group (P < 0.05). There was no difference in sex composition, degree of education, smoking index, past medical history, RV, incidence of ventilator-associated pneumonia, duration of invasive mechanical ventilation, length of ICU stay, or frequency of reintubation between the two groups (P >0.05). Multivariable Logistic regression analysis showed that PaO2 < 60 mmHg [O^R = 2.862, (95% CI: 1.482, 5.527) ], FEV1/FVC < 50% [O^R = 2.834, (95% CI: 2.070, 3.880) ], ALB < 30.00 g/L [O^R = 2.268, (95% CI: 1.032, 4.984) ], and PA < 145.00 g/L [O^R = 2.282, (95% CI: 1.123, 4.637) ] were risk factors for risk of malnutrition in AECOPD patients undergoing invasive mechanical ventilation (P < 0.05). ROC curve analysis exhibited that the sensitivity, specificity, and the area under the ROC curve (AUC) of the combined detection of PaO2, FEV1/FVC, ALB and PA for predicting the risk of malnutrition in AECOPD patients undergoing invasive mechanical ventilation were 89.1% (95% CI: 0.835, 0.967), 95.9% (95% CI: 0.856, 0.978), and 0.925 (95% CI: 0.870, 0.980), respectively.Conclusions PaO2, FEV1/FVC, ALB and PA are independent risk factors for risk of malnutrition in AECOPD patients undergoing invasive mechanical ventilation. The combination of these indicators is a promising predictor for early occurrence of risk of malnutrition.