Has the robot caught up? National trends in utilization, perioperative outcomes, and cost for open, laparoscopic, and robotic pediatric pyeloplasty in the United States from 2003 to 2015.
INTRODUCTION
Since 2010, there have been few new data comparing perioperative outcomes and cost between open (OP) and robotic pyeloplasty (RP). In a post-adoption era, the value of RP may be converging with that of OP.


OBJECTIVE
To 1) characterize national trends in pyeloplasty utilization through 2015, 2) compare adjusted outcomes and median costs between OP and RP, and 3) determine the primary cost drivers for each procedure.


STUDY DESIGN
We performed a retrospective cohort study using the Premier database, which provides a nationally representative sample of U.S. hospitalizations between 2003 and 2015. ICD9 codes and itemized billing were used to abstract our cohorts. Trends in utilization and cost were calculated and then stratified by age. We used propensity scores to weight our cohorts and then applied regression models to measure differences in the probability of prolonged operative time (pOT), prolonged length of stay (pLOS), complications, and cost.


RESULTS
During the study period 11,899 pyeloplasties were performed: 75% open, 10% laparoscopic, and 15% robotic. The total number of pyeloplasty cases decreased by 7% annually; OP decreased by a rate of 10% while RP grew by 29% annually. In 2015, RP accounted for 40% of cases. The largest growth in RPs was among children and adolescents. The average annual rate of change in cost for RP and OP was near stagnant: -0.5% for open and -0.2% for robotic. The summary table provides results from our regression analyses. RP conferred an increased likelihood of pOT, but a reduced likelihood of pLOS. The odds of complications were equivalent. RP was associated with a significantly higher median cost, but the absolute difference per case was $1060.


DISCUSSION
Despite advantages in room and board costs for RP, we found that the cost of equipment and OR time continue to make it more expensive. Although the absolute difference may be nominal, we likely underestimate the true cost because we did not capture amortization, hidden or down-stream costs. In addition, we did not measure patient satisfaction and pain control, which may provide the non-monetary data needed for comparative value.


CONCLUSION
Despite an overall decline in pyeloplasties, RP utilization continues to increase. There has been little change in cost over time, and RP remains more expensive because of equipment and OR costs. The robotic approach confers a reduced likelihood of pLOS, but an increased likelihood of pOT. Complication rates are low and similar in each cohort.