Comparison of Prediction Rules and Clinician Suspicion for Identifying Children With Clinically Important Brain Injuries After Blunt Head Trauma.

OBJECTIVE: Children with minor head trauma frequently present to emergency departments (EDs). Identifying those with traumatic brain injuries (TBIs) can be difficult, and it is unknown whether clinical prediction rules outperform clinician suspicion. Our primary objective was to compare the test characteristics of the Pediatric Emergency Care Applied Research Network (PECARN) TBI prediction rules to clinician suspicion for identifying children with clinically important TBIs (ciTBIs) after minor blunt head trauma. Our secondary objective was to determine the reasons for obtaining computed tomography (CT) scans when clinical suspicion of ciTBI was low. METHODS: This was a planned secondary analysis of a previously conducted observational cohort study conducted in PECARN to derive and validate clinical prediction rules for ciTBI among children with minor blunt head trauma in 25 PECARN EDs. Clinicians recorded their suspicion of ciTBI before CT as <1, 1-5, 6-10, 11-50, or >50%. We defined ciTBI as 1) death from TBI, 2) neurosurgery, 3) intubation for more than 24 hours for TBI, or 4) hospital admission of 2 nights or more associated with TBI on CT. To avoid overfitting of the prediction rules, we performed comparisons of the prediction rules and clinician suspicion on the validation group only. On the validation group, we compared the test accuracies of clinician suspicion > 1% versus having at least one predictor in the PECARN TBI age-specific prediction rules for identifying children with ciTBIs (one rule for children <2 years [preverbal], the other rule for children >2 years [verbal]). RESULTS: In the parent study, we enrolled 8,627 children to validate the prediction rules, after enrolling 33,785 children to derive the prediction rules. In the validation group, clinician suspicion of ciTBI was recorded in 8,496/8,627 (98.5%) patients, and 87 (1.0%) had ciTBIs. CT scans were obtained in 2,857 (33.6%) patients in the validation group for whom clinician suspicion of ciTBI was recorded, including 2,099/7,688 (27.3%) of those with clinician suspicion of ciTBI of <1% and 758/808 (93.8%) of those with clinician suspicion >1%. The PECARN prediction rules were significantly more sensitive than clinician suspicion >1% of ciTBI for preverbal (100% [95% confidence interval {CI} = 86.3% to 100%] vs. 60.0% [95% CI = 38.7% to 78.9%]) and verbal children (96.8% [95% CI = 88.8% to 99.6%] vs. 64.5% [95% CI = 51.3% to 76.3%]). Prediction rule specificity, however, was lower than clinician suspicion >1% for preverbal children (53.6% [95% CI = 51.5% to 55.7%] vs. 92.4% [95% CI = 91.2% to 93.5%]) and verbal children (58.2% [95% CI = 56.9% to 59.4%] vs. 90.6% [95% CI = 89.8% to 91.3%]). Of the 7,688 patients in the validation group with clinician suspicion recorded as <1%, CTs were nevertheless obtained in 2,099 (27.3%). Three of 16 (18.8%) patients undergoing neurosurgery had clinician suspicion of ciTBI <1%. CONCLUSIONS: The PECARN TBI prediction rules had substantially greater sensitivity, but lower specificity, than clinician suspicion of ciTBI for children with minor blunt head trauma. Because CT ordering did not follow clinician suspicion of <1%, these prediction rules can augment clinician judgment and help obviate CT ordering for children at very low risk of ciTBI.

Accuracy of the abdominal examination for identifying children with blunt intra-abdominal injuries.

OBJECTIVE: To determine the accuracy of complaints of abdominal pain and findings of abdominal tenderness for identifying children with intra-abdominal injury (IAI) stratified by Glasgow Coma Scale (GCS) score. STUDY DESIGN: This was a prospective, multicenter observational study of children with blunt torso trauma and a GCS score ≥13. We calculated the sensitivity of abdominal findings for IAI with 95% CI stratified by GCS score. We examined the association of isolated abdominal pain or tenderness with IAI and that undergoing acute intervention (therapeutic laparotomy, angiographic embolization, blood transfusion, or ≥2 nights of intravenous fluid therapy). RESULTS: Among the 12 044 patients evaluated, 11 277 (94%) had a GCS score of ≥13 and were included in this analysis. Sensitivity of abdominal pain for IAI was 79% (95% CI, 76%-83%) for patients with a GCS score of 15, 51% (95% CI, 37%-65%) for patients with a GCS score of 14, and 32% (95% CI, 14%-55%) for patients with a GCS score of 13. Sensitivity of abdominal tenderness for IAI also decreased with decreasing GCS score: 79% (95% CI, 75%-82%) for a GCS score of 15, 57% (95% CI, 42%-70%) for a GCS score of 14, and 37% (95% CI, 19%-58%) for a GCS score of 13. Among patients with isolated abdominal pain and/or tenderness, the rate of IAI was 8% (95% CI, 6%-9%) and the rate of IAI undergoing acute intervention was 1% (95% CI, 1%-2%). CONCLUSION: The sensitivity of abdominal findings for IAI decreases as GCS score decreases. Although abdominal computed tomography is not mandatory, the risk of IAI is sufficiently high that diagnostic evaluation is warranted in children with isolated abdominal pain or tenderness.

Computed tomography with intravenous contrast alone: the role of intra-abdominal fat on the ability to visualize the normal appendix in children.

BACKGROUND: Computed tomography (CT) with enteric contrast is frequently used to evaluate children with suspected appendicitis. The use of CT with intravenous (IV) contrast alone (CT IV) may be sufficient, however, particularly in patients with adequate intra-abdominal fat (IAF). OBJECTIVES: The authors aimed 1) to determine the ability of radiologists to visualize the normal (nondiseased) appendix with CT IV in children and to assess whether IAF adequacy affects this ability and 2) to assess the association between IAF adequacy and patient characteristics. METHODS: This was a retrospective 16-center study using a preexisting database of abdominal CT scans. Children 3 to 18 years who had CT IV scan and measured weights and for whom appendectomy history was known from medical record review were included. The sample was chosen based on age to yield a sample with and without adequate IAF. Radiologists at each center reread their site's CT IV scans to assess appendix visualization and IAF adequacy. IAF was categorized as "adequate" if there was any amount of fat completely surrounding the cecum and "inadequate" if otherwise. RESULTS: A total of 280 patients were included, with mean age of 10.6 years (range = 3.1 to 17.9 years). All 280 had no history of prior appendectomy; therefore, each patient had a presumed normal appendix. A total of 102 patients (36.4%) had adequate IAF. The proportion of normal appendices visualized with CT IV was 72.9% (95% confidence interval [CI] = 67.2% to 78.0%); the proportions were 89% (95% CI = 81.5% to 94.5%) and 63% (95% CI = 56.0% to 70.6%) in those with and without adequate IAF (95% CI for difference of proportions = 16% to 36%). Greater weight and older age were strongly associated with IAF adequacy (p < 0.001), with weight appearing to be a stronger predictor, particularly in females. Although statistically associated, there was noted overlap in the weights and ages of those with and without adequate IAF. CONCLUSIONS: Protocols using CT with IV contrast alone to visualize the appendix can reasonably include weight, age, or both as considerations for determining when this approach is appropriate. However, although IAF will more frequently be adequate in older, heavier patients, highly accurate prediction of IAF adequacy appears challenging solely based on age and weight.