Does renal parenchymal thickness affect bleeding in percutaneous nephrolithotomy ?

Aim: Blood loss is a major concern during percutaneous nephrolithotomy. The aim of this study was to evaluate the effect of access point parenchymal thickness on bleeding in percutaneous nephrolithotomy procedures. Materials and methods: In this study 85 patients who had undergone a percutaneous nephrolithotomy operation between February 2009 and July 2011 were reviewed retrospectively. All characteristics of the patients were investigated. The details of the operative procedure and the renal parenchymal thickness at the puncture site were also recorded. Blood loss was calculated during the peroperative and postoperative periods. Correlation and multivariate regression analysis were done to detect predictive factors on bleeding. Results: Of the 85 percutaneous nephrolithotomy procedures done, 12 (14.1%) patients had no diminution of hemoglobin value postoperatively and were excluded. This left 73 percutaneous nephrolithotomy procedures that were evaluated. The mean peroperative hemoglobin drop was 1.79 ± 1.17 mg/dL. Stone size, operation time, and grade of hydronephrosis were correlated with hemoglobin drop significantly (P = 0.047, P = 0.016, and P = 0.034, respectively). There was no correlation between parenchymal thickness and bleeding (P = 0.545). In multivariate regression analysis, only the operation time was found to be a statistically significant independent predictive factor for peroperative bleeding in percutaneous nephrolithotomy (P = 0.005). Conclusion: Renal parenchymal thickness and the grade of hydronephrosis do not predict peroperative hemorrhage in percutaneous nephrolithotomy procedures.Aim: Blood loss is a major concern during percutaneous nephrolithotomy. The aim of this study was to evaluate the effect of access point parenchymal thickness on bleeding in percutaneous nephrolithotomy procedures. Materials and methods: In this study 85 patients who had undergone a percutaneous nephrolithotomy operation between February 2009 and July 2011 were reviewed retrospectively. All characteristics of the patients were investigated. The details of the operative procedure and the renal parenchymal thickness at the puncture site were also recorded. Blood loss was calculated during the peroperative and postoperative periods. Correlation and multivariate regression analysis were done to detect predictive factors on bleeding. Results: Of the 85 percutaneous nephrolithotomy procedures done, 12 (14.1%) patients had no diminution of hemoglobin value postoperatively and were excluded. This left 73 percutaneous nephrolithotomy procedures that were evaluated. The mean peroperative hemoglobin drop was 1.79 ± 1.17 mg/dL. Stone size, operation time, and grade of hydronephrosis were correlated with hemoglobin drop significantly (P = 0.047, P = 0.016, and P = 0.034, respectively). There was no correlation between parenchymal thickness and bleeding (P = 0.545). In multivariate regression analysis, only the operation time was found to be a statistically significant independent predictive factor for peroperative bleeding in percutaneous nephrolithotomy (P = 0.005). Conclusion: Renal parenchymal thickness and the grade of hydronephrosis do not predict peroperative hemorrhage in percutaneous nephrolithotomy procedures