Khanna A. et al., 2019: Ureteral Stent Placement during Shockwave Lithotripsy: Characterizing Guideline Discordant Practice
Khanna A, Monga M, Sun D, Gao T, Schold J, Abouassaly R. Glickman Urologic and Kidney Institute, Cleveland Clinic, Cleveland, OH.
Quantitative Health Science, Cleveland Clinic, Cleveland, OH.
OBJECTIVES: To describe utilization patterns of ureteral stent placement during ESWL.METHODS: The Healthcare Cost and Utilization Project (HCUP) State Inpatient andAmbulatory Surgery Databases for Florida (2010-2012), Iowa (2010-2012), California (2010-2011), and New York (2006-2012) were used to identify patients undergoing ESWL with or without concomitant ureteral stent placement. Multivariate logistic regression was used to identify factors associated with ureteral stent placement. Post-operative ER visits and reoperation were compared between groups with multivariate logistic regression. RESULTS: A total of 128,040 patients undergoing ESWL during the study period were identified. Concomitant ureteral stent placement during ESWL was performed in 20,800 (16.2%) cases. Stent placement was more common among older patients (odds ratio [OR] 1.003 per year, 95% confidence interval 1.002-1.004) and those with greater co-morbidity burden (OR 1.10, 1.09-1.11), but also among those with higher income (OR 1.13, 1.08-1.19) and private insurance (OR 1.05, 1.01-1.10). Patients undergoing concomitant ureteral stent placement had higher rates of 30-day post-operative ER visits (8.9% vs 7.3%, p<0.0001) and 90-day reoperation (13.4% vs 8.2%, p<0.0001) compared to patients undergoing ESWL alone. CONCLUSIONS: A significant portion of patients treated with ESWL undergo concomitant ureteral stent placement, despite clinical guidelines over the last two decades discouraging this practice. Use of ureteral stent during ESWL appears driven by both clinical and non-clinical factors. Ureteral stent placement confers no perceivable advantage in post-operative ER visits or reoperation after ESWL based on administrative data from the HCUP.
Urology. 2019 Jun 21. pii: S0090-4295(19)30556-4. doi: 10.1016/j.urology.2019.06.015. [Epub ahead of print]
Guidelines published in 1997 (1), 2007 (2) and 2016 (3) discouraged the use of stents together with ESWL because of lack of outcome advantages.
On first glance the results of the present study seem to suggest a clear and significant misuse of stenting ESWL patients.
But interpretation of these statistical correlations is not easy: it is not known if stenting was done for renal or ureteral stones or if stenting was done in emergency situations. In addition the causal interpretation of single data done by the authors is very speculative.
From a mere mathematical/statistical point of view t is of course not allowed to combine the most significant ORs of the multivariate analysis to construct a fictional character (Table with pooled data from the present publication):
But it indirectly illustrates the problem of single data interpretation: An uninsured or rich female Hispanic living in a big city who does not pay for the procedure has the highest risk to be stented. ;-)
1 Segura, J. W., Preminber, G.M., Assimos, D.G. et al. Ureteral stones
clinical guidelines. Panel summary report on the management of ureteral calculi. J Urol 158, 1915–1921 (1997).
2 Preminger, G. M., Tiselius, H.G., Assimos, D.G. et al. 2007 Guideline for the
management of ureteral calculi. J Urol 178, 2418–2434 (2007).
3 Assimos, D. Krambeck, A., Miller, N.L. et al. Surgical management of stones:
AUA/Endourological Society Guideline, PART I. J Urol 196, 1153–1160 (2016).