Should helical CT scanning of the thoracic cavity replace the conventional chest x-ray as a primary assessment tool in pediatric trauma? An efficacy and cost analysis.

BACKGROUND/PURPOSE: Findings from studies in the trauma literature suggest that thoracic computed tomography (TCT) scanning should replace conventional radiographs as an initial imaging modality. Limited data exist on the clinical utility and cost of TCT scans in pediatric trauma. Our current practice is to obtain TCT scans in those children at risk for thoracic injures. The purpose of this study is to examine what additional information TCT provides, how frequently it results in a change in clinical management, and a cost/benefit analysis.

METHODS: Children 18 years old and younger that had both a Chest x-ray (CXR) and TCT scan in their initial workup were included. Indications for TCT scan were (1) any sign of thoracic injury on CXR, (2) pathologic findings on physical examination of the chest, and (3) high impact force to chest wall. A child may have had one or more indications for a TCT scan.

RESULTS: Between 1996 and 2000, 45 of 1,638 trauma patients met study criteria. Indications for TCT included thoracic injury on CXR (n = 27), findings on physical examination (n = 8) and high-impact force (n = 33). In 18 of the 45 (40%), injuries were detected with TCT imaging but not on CXR. These included contusions (n = 12), hemothorax (n = 6), pneumothorax (n = 5), widened mediastinum (n = 4), rib fractures (n = 2), diaphragmatic rupture (n = 1), and aortic injury (n = 1). In 8 patients (17.7%) TCT imaging resulted in a change in clinical management. These included insertion of a chest tube (n = 5) aortography (n = 2) and operation (n = 1). Age, sex, injury severity score, mechanism, and indication for TCT could not predict differences between TCT and CXR (P >.05). In our institution, the cost of a TCT is $200, and the patient charge is $906 ($94 per CXR). Based on our study data 200 TCTs would need to be done for each clinically significant change, increasing patient ($180,000) and hospital ($39,600) costs.

CONCLUSIONS: Helical TCT is a highly sensitive imaging modality for the thoracic cavity; however, routine CXR still provides clinically valuable information for the initial trauma evaluation at minimal cost. TCT should be reserved for selected cases and not as a primary imaging tool.