Percutaneous nephrolithotomy: variables that influence hemorrhage.

OBJECTIVES: Renal hemorrhage is one of the most common and worrisome complications of percutaneous nephrolithotomy (PCNL). This study attempted to identify variables that might influence hemorrhage during PCNL to help urologists establish preventative and treatment strategies for bleeding during PCNL procedures. METHODS: The data of 193 patients (193 PCNL procedures) were retrospectively analyzed. Hemorrhage was estimated by the postoperative decrease in hematocrit factored by the quantity of any blood transfusion. Various preoperative and operative factors were assessed for their association with blood loss using univariate, forward multivariate regression and correlation analysis. RESULTS: The mean patient age was 45.7 +/- 14.4 years (range 5 to 74). The overall stone-free rate was 85.4%. The average hematocrit decrease was 8.7% +/- 5.39% (range 0.3 to 24.7). Forward multivariate regression analysis identified five significant variables that influenced PCNL-related hemorrhage: stone type (P = 0.003), number of tracts (P = 0.010), method of dilation (P = 0.010), diabetes (P = 0.022), and stone surface area (P = 0.049). A statistically significant difference was found in relation to the occurrence of hemorrhage between patients with caliceal stones and partial staghorn stones (P = 0.008) and complete staghorn stones (P = 0.006), single tracts and multiple tracts (P = 0.038), balloon dilators and Amplatz dilators (P = 0.007), patients with small stones (1000 mm2 or smaller) and large stones (greater than 1000 mm2; P = 0.018) on univariate analysis. Also, the stone surface area (P = 0.019) and number of tracts (P = 0.024) showed a positive correlation with the mean hematocrit decrease. CONCLUSIONS: Staghorn stones, multiple tracts, the presence of diabetes, and large stones were associated with increased renal hemorrhage during PCNL on multivariate analysis. However, balloon dilation was associated with decreased hemorrhage.

How do increasing stone surface area and stone configuration affect overall outcome of percutaneous nephrolithotomy?

BACKGROUND AND PURPOSE: Studies reporting the outcome of percutaneous nephrolithotomy (PCNL) in relation to stone burden and configuration are limited. We analyzed our stone-free and complication rates of PCNL with regard to stone surface area and configuration. PATIENTS AND METHODS: Data of 234 patients who underwent PCNL were analyzed retrospectively. Patients were stratified into six groups according to stone burden and into four groups in relation to stone configuration. Groups were compared with respect to the number of tracts, success of therapy, complications, requirement for secondary procedures, drop in hematocrit, and blood transfusion requirement. RESULTS: The overall stone-free rate was 78.6% with a complication rate of 34.6%. Stone-free rates decreased with increasing stone size (P = 0.001) and with increasing caliceal component in complex stones (P = 0.01). The total number of complications rose with increasing stone surface area (P = 0.0001); however, stone distribution within the kidney did not affect the complication rate (P = 0.2). The mean operative time rose with increasing stone burden (P < 0.05) and increasing caliceal involvement by complex stones (P < 0.01). The need for multiple tracts also rose with increasing stone burden (P < 0.05). CONCLUSION: There is a decrease in the overall stone-free rate, as well as an increase in the complication rate, the secondary procedure rate, the mean operative time, and the need for multiple tracts, with increasing stone surface area with PCNL. With regard to stone configuration, there is a decrease in the stone-free rate, as well as an increase in the operative time, with increasing caliceal component in complex renal stones.