BackgroundPathological abdominal adhesions can cause bowel obstructions. A history of appendectomy (appy) increases patient rehospitalization risk directly related to adhesions. To potentially identify strategies for adhesion treatment, we characterized reactive ascites (rA) collected during appy or adhesiolysis for small bowel obstruction (SBO). MethodsThis is a non-randomized, prospective observational study recruiting patients with non-perforated appendicitis or SBO from three Level 1 trauma centers in the United States. rA were analyzed via liquid chromatography-mass spectrometry (LC-MS) (n = 31), bead-based quantification cytokines and chemokines (n = 32) and soluble receptors (n = 30), and LC-MS metabolomics (n = 18). ResultsLC-MS showed that samples contained albumin, apolipoprotein A1, and transthyretin and that metabolites increased in SBO vs appy rA were biomarkers of oxidative stress. Multi-plex analyses showed levels of 17 cytokines/chemokines and 6 soluble receptors were significantly different in appy vs SBO rA. Top increased proteins in appy compared to SBO rA by 20.14-, 11.53-, and 8.18-fold were granulocyte-colony stimulating factor, C-X-C motif chemokine ligand 10, and interleukin-10, respectively. ConclusionsThese data further define pro- and anti-inflammatory mediators and metabolites that may drive formation or perpetuate chronic abdominal adhesions. Future research is to further explore whether attenuation of these factors may decrease pathologic adhesion formation.