Does a smaller tract in percutaneous nephrolithotomy contribute to less invasiveness? A prospective comparative study

To determine the systemic response to percutaneous nephrolithotomy (PCNL) and mini-PCNL (MPCNL) and evaluate whether MPCNL is less invasive than PCNL, as experimental studies suggest that the acute-phase reaction is proportional to surgery-induced tissue damage.

In all, 165 consecutive patients who had undergone MPCNL (93) or PCNL (72) were prospectively assessed. Blood samples were collected 24 hours before; during surgery; at the end of anesthesia; and 12, 24, and 36 hours after surgery. The extent of the systemic response to surgery-induced tissue trauma was measured, by assessing the levels of acute-phase markers tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-10, C-reactive protein (CRP), and serum amyloid A (SAA), at all sampling times in all patients.

No significant differences were observed between the 2 groups in preoperative variables. Baseline levels of TNF-alpha, IL-6, IL-10, CRP, and SAA were comparable in both groups. An increase was noted in TNF-alpha, IL-6, CRP, and SAA after surgery but no significant differences were assessed between MPCNL and PCNL during the entire period. IL-10 did not change at the different sampling times.

Our data fail to demonstrate significant advantages of MPCNL in terms of reduced surgical trauma and associated invasiveness compared with standard PCNL based on the variables objectively measured in this study.