Operating Times and Bleeding Complications in Percutaneous Nephrolithotomy: a Comparison of Tract Dilation Methods in 5,537 Patients in the Clinical Research Office of the Endourological Society Percutaneous Nephrolithotomy Global Study

Purpose: The study investigated factors that affect operating times and bleeding complications associated with percutaneous nephrolithotomy (PCNL) in the PCNL Global Study.

Patients And Methods: All patients who underwent PCNL for primary or secondary treatment of kidney stone indications during the study period (November 2007-December 2009) were eligible for inclusion. PCNL procedures were performed according to local clinical guidelines and practices. Nephrostomy tract dilation was performed using balloon dilation, metal telescopic dilation, or Amplatz serial dilation. Hematologic complications assessed included bleeding rates, transfusion rates, and preoperative and postoperative hematocrit values.

Results: The median operating time with balloon dilation (n=2277) was significantly longer than with telescopic/serial dilation (n=3260) at 94.0 vs 60.0 minutes, respectively (P<0.0001). In the balloon dilation group, there was significantly more bleeding (9.4% vs 6.7%, respectively; P<0.0001) and more transfusions (7.0% vs 4.9%, respectively; P=0.001) compared with the telescopic/serial dilator group. Univariate analysis showed that the probability of bleeding complications was higher with balloon vs telescopic/serial dilation (odds ratio [OR] 1.75; P=0.0001) and larger sheath size (OR 1.42; P=0.0001). By multivariate analysis, sheath size but not dilation method was predictive of bleeding complications. Other significant predictive factors included operating time, stone load, and caseload.

Conclusion: This study shows that in PCNL, factors that are associated with bleeding/transfusion include sheath size, operating time, stone load, and caseload.