Low skeletal muscle mass predicts poor clinical outcomes in patients with abdominal trauma

The aim of this study was to investigate whether low skeletal muscle mass is associated with clinical outcomes in patients with abdominal trauma. Patients presenting to our institution with abdominal trauma from January 2010 to April 2020 were retrospectively included. Low skeletal muscle mass was defined, using computed tomography, as skeletal muscle index (SMI) at the third lumbar vertebra below the lowest sex-specific quartile within 1 wk of admission. Clinical outcomes such as complications, hospital stay, and hospital cost were recorded, and univariate and multivariate analyses were performed. Among 684 patients, 451 were eligible. Of these, 112 (24.8%) were classified as having low skeletal muscle mass, based on SMI diagnostic cutoff values (42.08 cm 2 /m 2 for men and 37.35 cm 2 /m 2 for women). Low skeletal muscle mass was significantly associated with longer hospital length of stay, longer intensive care length of stay, higher cost, higher frequency of mechanical ventilation, longer duration of vasopressor use, and higher incidence of massive transfusion and overall complications ( P < 0.05). Subgroup analysis showed that pneumonia, acute gastrointestinal dysfunction, cholecystitis, digestive tract fistula, gastric fistula, and intestinal fistula were significantly associated with low skeletal muscle mass ( P < 0.05). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for overall complications (odds ratio [OR], 2.44; 95% confidence interval [CI], 1.33–4.49; P = 0.004), hospital length of stay (OR, 3.49; 95% CI, 1.96–6.20; P < 0.001), and hospital cost (OR, 2.67; 95% CI, 1.48–4.80; P = 0.001). Low skeletal muscle mass could be an independent predictor of poor clinical outcomes in patients with abdominal trauma. • Patients with abdominal trauma are at high risk for low skeletal muscle mass. • Low skeletal muscle mass predicts poor clinical prognosis in abdominal trauma. • Assessment of skeletal muscle mass can help identify the postoperative risk. • Early recognition of skeletal muscle loss and treatment may improve prognosis.