Objectives: To determine predictors of Fluoroscopy Time (FT) during Percutaneous Nephrolithotomy (PCNL) and assess the impact of urology Post-Graduate Trainees (PGTs) and S.T.O.N.E. Nephrolithometry Score.
Methods: A prospective review of patients undergoing PCNL between 2010 and 2013 at a tertiary health care centre was performed. Patients’ demographics, stone characteristics, including S.T.O.N.E. Nephrolithometry Score, and operative data were compared among PGTs. Predictors of FT were determined using univariate and multivariate models.
Results: A total of 103 PCNLs were assisted by 10 PGTs from Post-Graduate Years (PGY) 4 and 5 [37 (35.9%) and 66 (64.1%) cases, respectively)]. Sixty percent of patients were males with a mean age of 55.2±1.5 years and a mean BMI of 26.4±0.5 kg/m2. The mean S.T.O.N.E score was 7.7±0.1, with tubeless PCNL in 53 (51.5%) cases. The mean FT was 120±5 seconds, mean operative time was 102±3.5 minutes and mean length of hospital stay was 4.2±0.34 days. The overall stone-free rate was 72.8%. PGY-5 trainees used significantly less FT than PGY-4 trainees (115±6 vs. 130±7 sec; p=0.04). FT significantly correlated with the number of involved calyces (r= 0.24, p= 0.02), number of punctures (r=0.6, p=0.01), number of tracts (r=0.4; p=0.01), and operative time (r=0.4, p=0.01). In addition, cases with estimated blood loss (EBL) 250 mL (109±5.1 vs. 148.2±10.9 sec; p=0.001). On multivariate analysis, the number of punctures, EBL and operative time were found to be independent predictors for FT. However, there was no correlation of FT with S.T.O.N.E. Nephrolithometry Score (r=0.16; p=0.1).
Conclusions: The number of punctures, EBL and operative time were the only independent predictors of prolonged FT during PCNL. |
