Role of plasma ammonia level in detecting intra-abdominal hemorrhage following blunt abdominal trauma

Blunt abdominal injury is a leading cause of death in trauma patients. A reliable test predicting intra-abdominal hemorrhage would be a novel method. The study objective was to assess the diagnostic accuracy of plasma ammonia in detection of intra-abdominal bleeding in patients with blunt abdominal trauma (BAT). In this observational study, all patients suffering from BAT, referred to our university teaching hospital included. The levels of ammonia were measured at the time of emergency department admission and 1 h after initial treatment. Demographic data, vital signs, and venous blood gas reports were recorded. Findings of contrast-enhanced abdominopelvic computed tomography scan and laparotomy were assumed as a gold standard for abdominal injuries. A total of 104 patients was enrolled in the study. 15 patients (14.4%) had intra-abdominal hemorrhage and the mean plasma ammonia level in this group was significantly higher than the other patients on admission time (101.73 ± 5.41? g/dL vs. 47.36 ± 26.31? g/dL, P < 0.001). On receiver-operator characteristic curve analysis, in cutoff point of 89? g/dL, the sensitivity, specificity, positive and negative likelihood ratios were 100% (95% confidence interval [CI], 79.6-100), 93.26% (95%CI, 86-96.8), 14.83 (95% CI, 6.84-32.12), and 0, respectively. The study findings suggest the measurement of ammonia level at the time of admission in the patients with BAT would be a useful test predicting intra-abdominal hemorrhage. Furthermore,decrease in the ammonia level could be a useful marker for monitoring response to treatment in these patients.