Analysis of percutaneous nephrostomy exchange intervals: insights from a retrospective Merative MarketScan analysis between 2009-2021.

Background: Current practices in nephrostomy exchange are guided by institutional or societal expert-consensus rather than evidence-based recommendations.

Objective: To examine the temporal distribution of exchanges and assess whether the observed distributions align with institutional, or expert-recommended guidelines where routine exchanges would be expected to occur within 60-89 days. Non-routine exchanges would be expected to occur either after 60 days or after 89 days.

Methods: Data were collected from the Merative™ MarketScan Commercial Claims and Encounters Databases and included all patients who underwent a PCN exchange from 2009 to 2021. The dataset was queried using ICD-9/10 and CPT coding systems. Outpatient exchanges were classified as routine exchanges, whereas inpatient exchanges were classified as non-routine exchanges. Chi-Square Goodness-of-Fit tests were used to compare observed frequencies against expected distributions of routine exchanges within the 59-89 day window, and non-routine exchanges to occur after either 60 or after 89 days.

Results: There was a total of 19,689 exchanges: of those, 41% (n = 8,058) exchange encounters occurred within 29 days, 67% (n = 13,213) occurred within 59 days, and 81% (n = 15,899) occurred within 89 days. Routine exchanges accounted for 76% of total exchanges: of those routine exchanges, 39% (n = 5,863) of routine exchanges occurred within 29 days, 67% (n = 10,057) occurred within 59 days, and 82% (n = 12,256) occurred within 89 days. Non-routine exchanges account for 24% of all exchanges in the study cohort. Of all non-routine exchanges (n = 4,737), 46% (n = 2,035) of non-routine exchange encounters occurred within 29 days, 67% (n = 3,156) within 60 days, and 77% (n = 3,643) within 89 days. Chi-square tests indicated significant deviations from the expected distributions for both routine (p < 0.01) and non-routine (p < 0.01) exchanges.

Conclusion: A significant proportion of routine exchanges occur outside a 60-89 day window, and with a majority of routine exchange observations occurring prior to 59 days. A significant proportion of non-routine exchanges occur prior to 60 days and prior to 89 days.

Clinical impact: Significant disparities between existing guidelines and clinical practice, underscoring the need for evidence-based guidelines to reduce complication rates, improve patient outcomes, and reduce the burden of cost on the healthcare system.