Use of ultrasonography in the patient with acute abdominal trauma

The purpose of this study was to assess the use of ultrasonography in patients with acute abdominal trauma. Five hundred prospective patients, who came to the Emergency Department with acute trauma, were evaluated with ultrasonography and included in this study. The ultrasonographic examination focused on detection of free fluid but included evaluation of parenchymal organs for injury. The physical examination was not used in the statistical analysis of the sonographic findings. In comparing ultrasonography to computed tomography, diagnostic peritoneal lavage, or operative findings, we obtained 24 true positive, 79 true negative, four false positive, and 14 false negative results. Sensitivity of ultrasonography in detecting free fluid in comparison to computed tomography, diagnostic peritoneal lavage, and surgery was 63%, specificity was 95%, accuracy was 85%, positive predictive value was 86%, and negative predictive value was 85%. The most common reason for false negative sonographic results was identification of free fluid in the pelvis on computed tomograms but not on ultrasonograms owing to lack of a full bladder. In none of these instances were the sonographic false negative results of clinical significance. Ultrasonography allowed detection of solid organ injury of the liver in one of seven cases, of the kidney in one of four cases, and in the bowel in zero of three cases. In the three instances of bowel injury, free fluid was noted on ultrasonograms. Ultrasonography fared better in cases of splenic laceration, permitting detection in nine of 14 cases. The emergent ultrasonogram may be used to detect free fluid in the abdomen of the acutely traumatized patient. However, sonography is limited in detecting free fluid in the pelvis using the present technique and does not allow visualization of organ injury. Limitations of this examination should be recognized for appropriate triage of the acutely traumatized patient.