Prevalence and importance of pneumothoraces visualized on abdominal computed tomographic scan in children with blunt trauma.

BACKGROUND: Chest radiographs are routinely obtained for the identification of pneumothoraces in trauma patients. Computed tomographic (CT) scanning has a higher sensitivity for the detection of pneumothoraces, but the prevalence and importance of pneumothoraces detectable by CT scan but not by chest radiography in children sustaining blunt trauma is unclear. METHODS: We conducted a prospective observational cohort study of children less than 16 years old with blunt trauma undergoing both abdominal CT scan and chest radiography in the emergency department of a Level I trauma center over a 28-month period. All abdominal CT scans were interpreted by a single faculty radiologist. The chest radiographs of all patients with pneumothoraces detected on CT scan as well as a random sample of chest radiographs from pediatric blunt trauma patients without pneumothoraces on abdominal CT scan (in a ratio of four normals per pneumothorax) were reviewed by a second faculty radiologist. Both radiologists were masked to all clinical data as well as to the objective of the study. RESULTS: Five hundred thirty-eight children underwent both abdominal CT scan and chest radiography in the emergency department. Twenty patients (3.7%; 95% confidence interval [CI], 2.3-5.7%) were found to have pneumothoraces on CT scan. Of these 20 patients, 9 (45%; 95% CI, 23-68%) had pneumothoraces identified on initial chest radiography and 11 patients did not ("unsuspected pneumothoraces"). Twelve pneumothoraces were identified in these 11 patients; 6 were graded as minuscule and 6 as anterior according to a previously established scale. One patient with an unsuspected pneumothorax underwent tube thoracostomy. None of the 10 patients (0%; 95% CI, 0-26%) with unsuspected pneumothoraces who were managed without thoracostomy (including two patients who underwent positive pressure ventilation) had complications from their pneumothoraces. CONCLUSION: Less than half of pediatric blunt trauma patients with pneumothoraces visualized on abdominal CT scan had these pneumothoraces identified on initial chest radiograph. Patients with pneumothoraces identified solely on abdominal CT scan, however, uncommonly require tube thoracostomy.

Isolated intraperitoneal fluid on abdominal computed tomography in children with blunt trauma.

OBJECTIVE: To determine the frequency of isolated intraperitoneal fluid (IIF) on abdominal computed tomography (CT) in pediatric blunt trauma patients and the association between IIF and clinically identifiable intra-abdominal injuries (IAIs) in these patients. METHODS: The authors conducted a prospective observational study of consecutive children <16 years old with blunt torso trauma who underwent abdominal CT scanning while in the emergency department (ED). All patients were evaluated by a faculty emergency physician who documented the patient's physical examination. All CTs were interpreted by a single faculty radiologist masked to clinical data. The volume of intraperitoneal fluid was quantified (small, moderate, large) and the presence of organ injury visible on CT was noted. Patients were considered to have IIF if the CT demonstrated intraperitoneal fluid and no solid organ injury. Patients with IIF were followed through their hospitalizations or telephoned in one week if discharged home from the ED. RESULTS: Five hundred twenty-seven children with blunt trauma were enrolled into the study. The mean age (+/-SD) was 7.4 +/- 4.7 years, and the median pediatric trauma score was 10 (range -2 to 12). Eighty-eight patients (17%; 95% CI = 14% to 20%) had intraperitoneal fluid on CT scan and 42 (48%; 95% CI = 37% to 59%) of these patients had IIF. Of the 42 patients with IIF, five patients (all without abdominal tenderness and with a small amount of IIF on CT scan) were discharged to home from the ED and were well at telephone follow-up; the remaining 37 patients were hospitalized. Of the 42 patients with IIF, 7 patients (17%, 95% CI = 7 to 31%) had IAIs subsequently identified (all gastrointestinal injuries) during their evaluations. Six of the seven patients with IIF and subsequently identified IAIs had abdominal tenderness on examination in the ED. The remaining patient had a decreased level of consciousness. CONCLUSIONS: Isolated intraperitoneal fluid occurs in 8% of pediatric blunt trauma patients undergoing abdominal CT, and IAIs are subsequently identified in 17% of these patients. Patients with a small amount of IIF on CT who lack abdominal tenderness and have a normal level of consciousness are at low risk for subsequently identified IAIs.