title: Role of plasma ammonia level in detecting intra-abdominal hemorrhage following blunt abdominal trauma.
abstract: BACKGROUND
  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).
  
  
  METHODS
  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.
  
  
  RESULTS
  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 μg/dL vs. 47.36 ± 26.31 μg/dL, P < 0.001). On receiver-operator characteristic curve analysis, in cutoff point of 89 μg/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.
  
  
  CONCLUSIONS
  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.
authors: Department of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Davood
authors: D
authors: Farsi
authors: Department of Emergency Medicine, Mashad University of Medical Sciences, Mashad, Iran.
authors: Ali Akbar Khademi
authors: AA
authors: Fadaki
authors: Department of Internal Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Nahid
authors: N
authors: Kianmehr
authors: Department of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Saeed
authors: S
authors: Abbasi
authors: Department of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Mahdi
authors: M
authors: Rezai
authors: Department of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Mohammad
authors: M
authors: Marashi
authors: Department of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran.
authors: Mani
authors: M
authors: Mofidi
keywords: Bl1unt abdominal trauma; intra-abdominal hemorrhage; plasma ammonia level
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