title: Oral contrast agents for CT of abdominal trauma in pediatric patients: a comparison of dilute hypaque and water.
abstract: OBJECTIVE
  Dilute Hypaque Sodium is generally well accepted as an oral contrast agent for CT of pediatric patients who have experienced recent blunt abdominal trauma. However, Hypaque can cause complications. Using water as a substitute contrast agent eliminates these potential complications. The purpose of our study was to compare the performance of water with that of dilute Hypaque as an oral contrast agent. Our hypothesis was that we would find no significant difference in performance between the two agents in defining anatomic details of the hollow gastrointestinal tract.
  
  
  METHODS
  We performed a retrospective review of 74 CT scans obtained in infants and children who had received blunt abdominal trauma, scoring the quality of visualization of bowel structures, the presence of non-bowel-related findings, and the confidence level in making each assessment. The date range of the scans reviewed overlapped with the period in which the oral contrast material used for scanning such patients was switched from dilute Hypaque to water. Of the 74 CT scans that we reviewed, 53 were obtained with dilute Hypaque and 21 were obtained with water. The sex distribution between the two groups was compared using a chi-square test, whereas the mean age was compared using a two-sample two-sided Student's t test. A two-sample one-sided Student's t test of equivalence was used to analyze the data.
  
  
  RESULTS
  Sex distribution for the two groups of patients was not significantly different (69.81% of the group who received dilute Hypaque were boys; 68.18% of the group who received water were boys). Furthermore, the difference in the mean age for the two groups was not statistically significantly (dilute Hypaque group, 8.86 years; water group, 10.18 years). No statistically significant difference in performance of the contrast agents was found with respect to the detection of intraabdominal abnormality. As an oral contrast material, water performed as well as dilute Hypaque in facilitating visualization of all intraabdominal anatomic structures.
  
  
  CONCLUSIONS
  In defining anatomic details of the hollow gastrointestinal tract, water is as effective as dilute Hypaque as an oral contrast agent for CT in the setting of acute blunt abdominal trauma in pediatric patients.
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Halsted
authors.forename: John M
authors.initials: JM
authors.lastname: Racadio
authors.forename: Kathleen H
authors.initials: KH
authors.lastname: Emery
authors.forename: Peter
authors.initials: P
authors.lastname: Kreymerman
authors.forename: Stacy A
authors.initials: SA
authors.lastname: Poe
authors.forename: Judy A
authors.initials: JA
authors.lastname: Bean
authors.forename: Lane F
authors.initials: LF
authors.lastname: Donnelly
mesh_terms: D000007:Abdominal Injuries / Q000000981:diagnostic imaging*; D000284:Administration, Oral; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000008:administration & dosage*; D003973:Diatrizoate / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014867:Water / Q000008:administration & dosage*
chemical_list: D003287:Contrast Media; D014867:Water; D003973:Diatrizoate