Minimal pelvic fluid in blunt abdominal trauma in children: the significance of this sonographic finding.

PURPOSE

The aim of this study was to evaluate the significance of the ultrasonographic finding of pelvic fluid after blunt abdominal trauma in children as a predictor of an abdominal organ injury.

METHODS

The clinical and imaging data of 183 children with blunt abdominal trauma were reviewed retrospectively. All children had an abdominal sonography as the primary screening study. The ultrasound results were divided into 3 groups: group A, normal examination; group B, pelvic fluid only; group C, peritoneal fluid outside the pelvis. The results of the initial ultrasound examinations were compared with the findings of the CT scan, or a second ultrasound examination or the clinical course during the hospitalization.

RESULTS

Group A included 87 children; group B, 57, and group C, 39. Four abdominal organ injuries were missed by the ultrasound examination. The sensitivity and specificity of the ultrasound examinations to predict organ injury in presence of peritoneal fluid outside the pelvis were, respectively, 89.5% and 96.6%; the positive and negative predictive value were 87.2% and 97.3%. No statistically significant difference was seen between group A and group B, whereas the presence of peritoneal fluid outside the pelvic cavity (group C) was associated strongly with an organ injury (P <.001).

CONCLUSIONS

A normal ultrasound examination or the presence of pelvic fluid are associated with a low probability of an organ injury. In the presence of peritoneal fluid outside the pelvis, the probability of an organ injury is very high.