Use of internal stent, external transanastomotic stent or no stent during pediatric pyeloplasty: a decision tree...

Copious studies exist regarding the use of stents in pediatric pyeloplasty. Most surgeons use either no stent, an internal (Double-J®) stent or an external transanastomotic pyeloureteral stent. We propose the first known study to compare all 3 methods using a decision tree model that incorporates success rates, complications, patient discomfort and costs.

We created a deterministic decision tree model. We conducted a literature search querying urinary diversion in pediatric pyeloplasty. We used the largest studies for base inputs and remaining studies for sensitivity analysis. Direct costs from actual patients seen at the University of California San Francisco populated cost inputs.

Total quality adjusted life-years during a 16-year period for no stents was 12.70851 with a total cost of $6,122. Total quality adjusted life-years for external stents was 12.71098 at a total cost of $5,702. Internal stents resulted in total quality adjusted life-years of 12.69983 and cost of $8,421. Thus, external stents dominated no stents and internal stents, while no stents dominated internal stents. On sensitivity analysis even decreasing complication and failure rates of internal stents to zero did not make them cost effective due to the costs associated with stent removal. In contrast, decreasing complication and pyeloplasty rates of no stents by 20% resulted in an incremental cost-effectiveness ratio of $5,475 per quality adjusted life-year gained compared to external stents.

External and no stents are superior to internal stents. Given high overall success rates of pyeloplasty regardless of stent method, perhaps more attention should be given to cost from a health policy standpoint.