One-shot versus gradual dilation technique for tract creation in percutaneous nephrolithotomy: a systematic review and meta-analysis

The aim of this study is to evaluate the efficacy and safety of one-shot versus gradual dilation technique for tract creation in percutaneous nephrolithotomy (PCNL). A systematic research of Pubmed, Embase and the Cochrane Library was performed to identify all relevant studies. The quality of the included trials was assessed and the data were extracted independently by two reviewers. The Cochrane Collaboration's Review Manager (RevMan) 5.0.2 software was used for statistical analysis. Four randomized controlled trials were included in analysis involving 346 patients in total. Of these patients 174 were in the one-shot group and 172 in the gradual group. Our meta-analysis showed that there were no significant differences in successful dilation rate [risk ratio (RR): 0.96; 95 % confidence interval (CI): 0.92-1.00, p = 0.05], transfusion rate (RR: 0.62; 95 % CI: 0.20-1.96; p = 0.42), and hemoglobin decrease [mean difference (MD): -0.34; 95 % CI: from -0.67 to -0.00; p = 0.05] between one-shot dilation and gradual dilation. One-shot dilation had significant shorter access time (MD: -1.03; 95 % CI: from -1.57 to -0.49; p = 0.0002) and X-ray exposure time (MD: -42.71; 95 % CI: from -45.05 to -40.37; p < 0.00001) than gradual dilation. Our results show that One-shot dilation is an effective and safe procedure for tract creation in PCNL, with shorter access time and X-ray exposure time and without increased complications. As only four studies with small study populations were available, more high-quality larger trials with longer follow-up are recommended.