Time-Driven Activity-Based Cost Comparison of Three Imaging Pathways for Suspected Midgut Volvulus in Children

To use time-driven activity-based costing to compare the costs of pathways for evaluating suspected pediatric midgut volvulus using either fluoroscopic upper gastrointestinal examination (UGI) or focused abdominal ultrasound (US).

Process maps were created through patient shadowing, medical record review, and frontline staff interviews. Using time-driven activity-based costing methodology, practical capacity cost rates were calculated for personnel, equipment, and facility costs. Supply costs were included at institutional purchase prices. The cost of each process substep was determined by multiplying step-specific capacity costs by the median time required for each step, and substep costs were summed to generate total pathway cost. Multivariate sensitivity analyses were performed applying minimum and maximum labor costs. Assuming UGI would be used to troubleshoot nondiagnostic US, a break-even analysis was performed to determine the cost impact of varying frequencies of UGI on the total cost of the US-based pathway.

Process maps were created from 105 (48 girls, 57 boys) patient encounters. Base case pathway times were 90 min (UGI) and 55 min (US). Base case cost for UGI was $282.74 (range: $170.86-$800.82) when performed by a radiology practitioner assistant and $545.66 (range: $260.97-$1,974.06) when performed by a radiologist. Base case cost for US was $155.67 (range: $122.94-$432.29) when performed by a sonographer and $242.64 (range: $147.46-$1,330.05) when performed by a radiologist. For a US-based pathway, the total cost break-even pathway mix (percent UGI required for troubleshooting) was 57%.

US can be a faster and less costly alternative to UGI in pediatric patients with suspected midgut volvulus.