Severe Malnutrition Identified by the Controlling Nutritional Status (CONUT) Score Is Associated With Prolonged Intensive Care Unit (ICU) Stay in Pneumonia Complicated With Respiratory Failure Patients Who Underwent Invasive Mechanical Ventilation.

Background: Mechanical ventilation is an effective method to improve the ventilation of patients with severe pneumonia and respiratory failure. The length of intensive care unit (ICU) stay reflects the treatment effectiveness of patients. This study was to evaluate the relationship between Controlled Nutritional Status (CONUT) score and prolonged ICU stay in patients with pneumonia complicated by respiratory failure who underwent invasive mechanical ventilation.

Methods: 1994 patients who underwent invasive mechanical ventilation were retrospectively analyzed. Medical records (age, gender, body mass index, smoking, drinking, hypertension, diabetes mellitus, lung diseases, blood transfusion, and serum albumin, lymphocyte, cholesterol levels) were collected. The threshold for prolonged ICU stay was defined based on the third quartile (75th percentile) of length of ICU stay. The relationship between CONUT and prolonged ICU stay was analyzed.

Results: The mean ICU stay of patients was 6.6 (3.9, 11.6) days; there were 1495 (75.0%) patients without prolonged ICU stay (< 11.6 days) and 499 (25.0%) with prolonged ICU stay (≥ 11.6 days). The proportion of CONUT severe grade in patients with prolonged ICU stay was higher than that in patients without prolonged ICU stay. Logistic regression analysis showed that CONUT severe grade (odds ratio (OR): 1.298, 95% confidence interval (CI): 1.024-1.646, p = 0.031), smoking (OR: 1.475, 95% CI: 1.105-1.968, p = 0.008), and blood transfusion (OR: 2.981, 95% CI: 2.406-3.694, p < 0.001) were independently associated with prolonged ICU stay.

Conclusions: CONUT severe grade, smoking, and blood transfusion were independently associated with prolonged ICU stay in pneumonia with respiratory failure patients who underwent invasive mechanical ventilation.