Elevated Aminotransferases are Predictors of Hepatic Injury in Blunt Abdominal Trauma Patients

Abstract

Objective Computed tomography (CT) scan is currently the most commonly used tool for evaluating solid-organ injuries in trauma management. However, liberal use of CT scanning increases the risk of excess radiation exposure and toxicity from contrast material. Animal studies and clinical research on the paediatric population indicated that liver enzymes elevations were related to hepatic injury. The present study was undertaken to determine whether elevated liver enzymes were associated with the occurrence of hepatic injury in adult patients with blunt abdominal trauma. Methods This is a cross-sectional study from August 2003 to October 2006. All adult patients with blunt injury to abdomino-pelvic organs documented by CT or surgery who were admitted to Chi-Mei Medical Centre in the captioned period were included. The study population sorted to hepatic injury (HI) and no hepatic injury (NHI) groups according to the presence or absence of hepatic injury. Variables including liver enzymes were compared between the groups. Results Totally 419 patients were included, including 150 patients in the HI group and 269 patients in the NHI group. The HI group was younger and had a lower rate of laparotomy (36.3 years old vs 41.4 years old; 26% vs 42%, respectively). The mean levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the HI group were significantly higher than levels in the NHI group (439.6 IU/L vs 104.7 IU/L; 353.5 IU/L vs 76.6 IU/L, p<0.01). We define AST >200 IU/L or ALT level >125 IU/L as abnormal according to previous studies. The diagnostic characteristics of hepatic injury were 87.3% sensitivity, 80.3% specificity, 71.2% positive predictive value, and 91.9% negative predictive value. Conclusion In adults who have experienced blunt abdominal trauma, AST >200 U/L or of ALT >125 U/L are practical predictors of hepatic injury. Screening serum aminotransferases will have a role in detecting occult hepatic injury and may reduce the hazards of excessive CT scanning. (Hong Kong j.emerg.med. 2013;20:337-342)