A Multicenter Cross?sectional Study on Chronic Critical Illness and Surgery?related Chronic Critical Illness in China

Objective: To understand the prevalence, diagnosis and treatment of chronic critical illness (CCI) in China. Methods: The clinical data of 472 adult patients admitted to ICU in 53 hospitals, including basic information, disease-related data, nutrition program, etc., were collected on May 10, 2019, by means of multi-center cross-sectional study. If surgical intervention was needed or the occurrence of the disease was directly related to the surgery, ICU patients were regarded as surgical ICU cases (n=211). In this study, the diagnostic criteria for CCI were: (1) admission to ICU >14 days;(2) combined with persistent organ dysfunction. The prevalence,distribution and treatment of CCI and surgery-related CCI were recorded and analyzed. The Mann-Whitney U test, chi-square test or Fisher exact test were used for comparative analysis. Results: Among the 472 ICU patients from 53 hospitals, 326 were male (69.1%) and 146 were female (30.9%). The prevalence of CCI was 30.7% (145/472). Among 211 surgery-related ICU patients, 57 developed CCI with a prevalence of 27.0%. As compared to non-CCI patients, higher APACHE II score [median (IQR) 13.5 (10.0, 18.3) vs. 11.0 (7.0, 16.0), U=2970.000, P=0.007], higher Charlson comorbidity index [median (IQR) 4.0 (2.0, 7.0) vs. 3.0 (1.0, 5.0), U= 3570.000, P=0.036] and higher ratio of breath dysfunction [68.4% (39/57) vs. 48.1% (74/154), χ(2)=6.939, P=0.008] and renal dysfunction [42.1% (24/57) vs. 18.2% (28/154), χ(2)=12.821, P<0.001] were found in surgery-related CCI patients. While SOFA score, Glasgow coma score and other visceral function were not significantly different between surgery-related CCI and non-CCI patients (all P>0.05). NUTRIC score showed that surgery-related CCI patients had higher nutritional risk [43.9% (25/57) vs. 26.6%(41/154), U=5.750, P=0.016] and higher ratio of mechanical ventilation [66.7% (38/57) vs. 52.3% (79/154), χ(2)=3.977, P=0.046] than non-CCI patients. On the survey day, the daily caloric requirements of 50.2% (106/211) of surgery-related ICU patients were calculated according to the standard adult caloric intake index (104.6 to 125.5 kJ·kg(-1)·d(-1), 1 kJ=0.239 kcal), and the daily caloric requirements of 46.4% (98/211) of patients were calculated by physicians according to the severity of the patient's condition. 60.2% (127/211) of nutritional support therapy was enteral nutrition (including a combination of enteral and parenteral nutrition), while the remaining patients received parenteral nutrition (24.6%, 52/211), simple glucose infusion (9.0%, 19/211), or oral diet (6.2%, 13/211). The target calorie of CCI group was 104.6 (87.9, 125.5) kJ·kg(-1)·d(-1), and the actual calorie intake accounted for 0.98 (0.80, 1.00) of the target calory. In the non-CCI group, the target calorie was 104.6 (87.9, 125.5) kJ·kg(-1)·d(-1), and the actual calorie consumed accounted for 0.91 (0.66, 1.00) of the target calorie. There was no statistically significant difference between two groups (P=0.248, P=0.150). Conclusion: The prevalence of CCI and surgery-related CCI in ICU is high, along with severe complications, respiratory and renal dysfunction and mechanical ventilation. Surgical patients admitted to ICU are at high nutritional risk, and active and correct nutritional support is essential for such patients.