EAU 2006 - ABST [494] Predictors of perioperative course and clinical outcome in patients undergoing PCNL for extensive stone disease. Results from 3 centres in Germany and Malaysia
INTRODUCTION & OBJECTIVES: PCNL with modern stone disintegration technologies is the treatment of choice for patients with extensive stone burden or stones refractory to extracorporeal shock wave lithotripsy. However, little is known about factors predicting unfavourable outcome in terms of perioperative complications, residual stone burden or prolonged hospitalization. Aim of this study was to evaluate preoperative, patient related parameters influencing the perioperative course and /or clinical outcome in 2 patient cohorts from central Europe and South East Asia treated by LithoClast® Master/Ultra.
MATERIAL & METHODS: In a prospective study, age, sex, body mass index, bi-dimensional size, stone composition (infection stone or not), and side were used as independent variables in a univariate and multivariate regression model in 141 PCNL (32 Malaysia, 109 Germany) patients to predict duration of surgery, the occurrence of complications (relevant bleeding, postoperative urinoma, sepsis, fistula), postoperative residuals not likely to pass spontaneously (>4 mm) and the duration of inpatient treatment. Calculations were performed for all individuals and separately for the German and Malaysian centres.
RESULTS: Univariate regression analysis revealed stone size to be the only factor influencing duration of surgery (p = 0.0001) and hospitalization (p = 0.024). This was confirmed in multivariate analysis. Univariate analysis showed a trend towards higher complication rates in older patients (p = 0.07) however this was not reproducible after controlling for the other confounding variables. The other patient related factors, especially BMI and stone composition did not adversely affect the outcome parameters. Moreover stone size was not a predictor of postoperative stone free status. Stone free rates were slightly higher (92 vs. 83 %, n.s.) in Malaysia. Complication rates and duration of surgery were comparable.
CONCLUSIONS: PCNL by LithoClast® Master/Ultra appears to be a highly standardized and effective technique in percutaneous stone surgery. Its success and safety is not significantly influenced by patient related factors. Large stone burden predicts longer surgery. In these patients, auxiliary interventions like large bore nephrostomy tubes or stents might be responsible for longer hospitalization.