Shockwave Lithotripsy Use in the State of Michigan: American Urological Association Guideline Adherence and Clinical Implications

Abstract

To understand how treatment of patients with urinary stones by shockwave lithotripsy (SWL) aligns with current published practice guidelines. We used the Michigan Urologic Surgery Improvement Collaborative Reducing Operative Complications for Kidney Stones registry to understand SWL use in the state of Michigan. This prospectively maintained clinical registry includes data from community and academic urology practices and contains clinical and operative data for patients undergoing SWL and ureteroscopy (URS). We identified patients undergoing SWL from 2016 to 2019. In accordance with AUA guidelines, we evaluated practice patterns in relation to recommendations for treatment selection for SWL as well as clinical implications of guideline nonadherence. Four thousand, two hundred and nine SWL procedures performed across 34 practices were analyzed. Perioperative antibiotics were administered to 61.3% of patients undergoing SWL. A ureteral stent was placed at the time of SWL in 2.7% of patients. For lower pole renal stones >1 cm or large (>2 cm) renal stones in the registry, 32.2% and 58.9% of patients, respectively, underwent SWL, while the remainder were treated with URS. In these instances, SWL was associated with inferior stone-free rate (SFR) relative to URS. In patients with residual stones after SWL, 34.6% were treated with repeat SWL with lower SFR than those treated with subsequent URS. Postoperatively, 42.1% of patients were prescribed alpha-blockers with no benefit seen in terms of SFR. Substantial variation exists among urology practices with regard to SWL use. These data serve to inform quality improvement efforts regarding appropriateness criteria for SWL in Michigan.