To study the clinical value of serum citrulline in predicting acute gastrointestinal injury at different time after multiple trauma.

Forty patients with multiple trauma, admitted to the ICU of Shanghai General Hospital from June 2017 to February 2018, were studied prospectively. These patients were first divided into mild trauma group (ISS<16, n=21) and severe trauma group (ISS≥16, n=19) according to the injury severity score (ISS), and then subdivided into AGI 0 (n=12), AGI Ⅰ (n=9), AGI Ⅱ(n=14) and AGI Ⅲ group (n=5) based on their acute gastrointestinal injury (AGI) grade. 10 healthy people were selected as the control group. On day 1, day 3 and day 6, the levels of citrulline were detected by high-performance liquid chromatography (HPLC), and the levels of diamineoxidase, D-lactate and endotoxin were detected by analysis system of biochemical indexes of intestinal barrier function.

Compared with the control group, serum citrulline levels were decreased significantly in both mild trauma group and severe trauma group on day 1, day 3 day 6 (P<0.05). Serum citrulline levels were lower in severe trauma group than those in mild trauma group on day 1 (P<0.05). In mild trauma group, serum citrulline were decreased further on day 3 compared to serum citrulline on day 1 (P<0.05). Serum citrulline levels were lower in both mild trauma group and severe trauma group than those in control group on day 6. The higher grade of AGI, the lower level of serum citrulline (P<0.05). In all AGI subgroups, serum citrulline levels on day 3 were further decreased compared to day 1(P<0.05). Serum citrulline level was negatively associated with number of ICU days, ISS score, AGI grade, serum diamineoxidase level and D-lactate level. Serum citrulline≤19.56 μmol/L may be the best value of predicting AGI after severe trauma.

Serum citrulline has some clinical value in predicting early intestinal dysfunction in patients with severe multiple trauma.