Background and purpose: Operative time influences surgical outcomes, operation-related and indirectly anesthesia-related complications. We investigated variables that affect operative time during percutaneous nephrolithotomy (PCNL) with the complete supine position.
Patients and methods: We reviewed data of 120 patients who underwent complete supine PCNL by one surgeon. Correlation between age, sex, body mass index (BMI), preoperative serum creatinine and hemoglobin levels, history (stone surgery, shockwave lithotripsy (SWL), hypertension, diabetes), stone (side, opacity, burden, complexity), imaging for access, calix for access, number of tracts, and tubeless approach with operative time were assessed by univariate and multivariate statistical tests.
Results: Mean operative time was 60.62±30.70 minutes. In univariate analysis, age, sex, groups of BMI, hypertension, diabetes, previous stone surgery and SWL, stone opacity, operation side, number of tracts, and tubeless approach had no effect on operative time. BMI (P=0.029, negative correlation), stone burden (P=0.001, positive correlation), imaging for access (P=0.001, fluoroscopy<ultrasonography), calix for access (P=0.035, upper>lower>middle) and probably complex stones (P=0.057, complex>noncomplex) were effective factors on operative time. Multiple linear regression revealed association between BMI (P=0.000, negative correlation), stone burden (P=0.005, positive correlation), imaging for access (P=0.000, fluoroscopy<ultrasonography), and calix for access (P=0.023) with operative time. In lower calix access, mean operative time was less than upper calix access (P=0.022, significant) and higher than middle calix access (P=0.930, nonsignificant).
Conclusions: BMI, stone burden, imaging for access, and calix for access were effective parameters on operative time in complete supine PCNL. Groups of BMI, previous stone surgery and SWL, number of tracts, and tubeless approach had no effect on operative time.