Clinical application of Acutegastrointestinal injury grading system assocaited with clinical severity outcome in critically ill patients: a multi-center prospective, observational study

Abstract

Objective: To investigate the feasibility of utilizing the current acute gastrointestinal injury(AGI) grading system, and explore the association of severity of AGI grade with clinical outcome in critically ill patients. Methods: The adult patients from 14 general ICUs in Zhejiang Province with an expected admission to ICU for at least 24 h were recruited, and all clinical, laboratory, and survival data were prospectively collected. The AGI grade was daily assessed based on GIsymptoms, feeding details and organ dysfunctionon the first week of admission to ICU.The intra-abdominal pressures(IAP) was measured using AbViser device. Results: Of 550 patients enrolled, mean values for age and APACHE Ⅱ score were (64.9±17.2) years and (19.5±7.4), respectively. 456 patients(82.9%) took mechanical ventilation, and 470 patients were identified for AGI. The distribution of AGI grade on the frist day of ICU admission were 50.6%(Ⅰ grade, n=238), 34.2%(Ⅱ grade, n=161), 12.4%(Ⅲ grade, n=58) and 2.8%(Ⅳ, n=13), respectively, while the distribution of the global AGI grade based on the 7-day AGI assessment of ICU admission were 24.5%(Ⅰ grade, n=115), 49.4%(Ⅱ grade, n=232), 20.6%(Ⅲ grade, n=97) and 5.5%(Ⅳ, n=26), respectively. 28- and 60-day mortality rate was 29.3%(n=161) and 32.5%(n=179), respectively. The patients with AGI had a higher 28-(31.1% vs 18.8%, P=0.025) and 60-day survival rate(34.7% vs 20.0%, P=0.01) than those with non-AGI, and also there were positive correlations between AGI grade and 28- and 60-day mortality(P<0.001). Univariate Cox regression analysis showed that age, the source of medicial admission, diabetes mellitus, coronary heart disease, the use of vasoactive drugs, serum creatinine and lactate, mechanical ventilation, APACHE Ⅱ score, the AGI grade in the first day of ICU admission and feeding intolerance within the first week of ICU stay were significantly(P≤0.02) associated with mortality. In multivariate analysis including all these variables, the source of medical admission(χ(2)=4.34, P=0.04), diabete mellitus(χ(2)=3.96, P=0.05), the use of vasoactive drugs(χ(2)=6.55, P=0.01), serum lactate(χ(2)=4.73, P=0.03), the global AGI grade in the 7-day of ICU admission(χ(2)=7.10, P=0.008), and APACHE Ⅱ score(χ(2)=12.1, P<0.001) remained independent predictors for 60-day mortality.In the further subgroup analysis including 402 patients with 7-day survival, the feeding intolerance within the first week of ICU stay could provide independent and incremental prognostic value of 60-day mortality wtih increased χ(2)value of Cox regression model(χ(2)=52.2 vs 41.9, P=0.007) . Conclusion: The AGI grading system is useful for identifying the severity of gastrointestinal dysfunction, and could be used as a strong predictor of impaired outcome. The results provide evidence to support that feeding intolerance within 7 days of admission to ICU was an independent determinant of mortality.