Examination of the role of abdominal computed tomography in the evaluation of victims of trauma with increased aspartate aminotransferase in the era of focused abdominal sonography for trauma.

BACKGROUND

Current evaluation of patients with negative findings on a focused abdominal sonography for trauma scan and an isolated increase of admission hepatic enzymes includes abdominal computed tomography (CT). Many of these patients do not have clinically important hepatic injuries. The purpose of this study was to establish the admission aspartate aminotransferase (AST) level below which patients do not need an abdominal CT for injury evaluation and treatment.

METHODS

Patients who were hemodynamically stable, had a focused abdominal sonography for trauma scan with negative findings, and an AST level greater than 200 IU/L were identified over a 1-year period. Medical records were reviewed for demographics, injuries sustained, mechanism, evaluation, interventions, and complications.

RESULTS

A total of 67 patients, mostly with blunt trauma, were identified; 42 (63%) had an AST level < 360 IU/L, and 25 (37%) had an AST level > 360 IU/L. Patients with an AST level > 360 IU/L had a 88% chance of having any hepatic injury and a 44% chance of having an injury of grade III or greater (P =.0001). Patients with an AST level of < 360 IU/L only had a 14% chance of having a liver injury and no chance of having an injury of grade III or greater (P =.036).

CONCLUSIONS

Clinically important hepatic injuries are not missed if an abdominal CT is only performed for patients with a focused abdominal sonography for trauma scan with negative findings and an AST level of > 360 IU/L. Eliminating unnecessary CT allows for more cost-effective use of resources.