Supplementary Material for: Does Body Mass Index Impact the Outcomes of Ultrasound-Guided Percutaneous Nephrolithotomy?

<b><i>Background and Purpose:</i></b> To evaluate whether body mass index (BMI) has an impact on the outcomes of ultrasound-guided percutaneous nephrolithotomy (PCNL). <b><i>Materials and Methods:</i></b> The data of 359 patients who required PCNL at ShengJing hospital between June 2013 and July 2015 were reviewed, with the patients divided into 4 groups based on different ranges of BMI: &lt;25, 25–29.9, 30–34.9, and ≥35 kg/m². Baseline characteristics and outcomes were compared between the groups. Multivariable logistic regressions were used to evaluate the independent contribution of BMI as a predictor of outcomes. The Modified Clavien classification system was used for reporting complications. Results were compared between the groups using the chi-square and multivariate logistic regression tests. <b><i>Results:</i></b> No significant differences were noted in the demographic data between the 4 groups. Ultrasound screening time, total operative time, and hospital stay all increased with increasing BMI. No difference was found in the complication rate, stone free rate, or need for auxiliary procedures. <b><i>Conclusion:</i></b> Obesity does not increase the incidence of complications in ultrasound-guided PCNL, and the efficacy of the technique for obese patients is similar to that for normal weight patients. The lateral decubitus position was preferred in patients with higher BMI.