One-shot dilation versus serial dilation technique for access in percutaneous nephrolithotomy: a systematic review and meta-analysis

OBJECTIVE: The purpose of this study was to systematically review the outcomes of the use of one-shot dilation (OSD) and serial tract dilation for percutaneous nephrolithotomy (PCNL). METHODS: A systematic review and meta-analysis was conducted. The randomised controlled trials (RCTs) included in the study were identified from EMBASE, MEDLINE and the Cochrane Central Register of Controlled Trials. The last search was performed on 30 April 2018. Summary effects were calculated as risk ratios (RRs) with 95% CIs or mean differences (MDs) with 95% CIs. The endpoints included access time, fluoroscopy time, successful dilation rate, stone-free rate, postoperative decrease in haemoglobin levels, transfusion rate, complication rate and length of postoperative hospital stay. RESULTS: A total of seven RCTs were included in the study, with clinical data reported for 697 patients. The overall access time was approximately 110 s shorter in the OSD group than in the serial dilation group (MD, −110.14; 95% CI −161.99 to −58.30; p<0.0001). The fluoroscopy time was shorter with OSD in all RCTs. In addition, the decrease in postoperative haemoglobin levels was approximately 2.3g/L less in patients in the OSD group than in those in the serial dilation group (MD, −0.23; 95% CI−0.39 to −0.07; p=0.004). No relationship was found between the successful dilation rate, stone-free rate, transfusion rate, or complication rate and the method of tract dilation. CONCLUSION: OSD is a safe and efficacious tract dilation technique that can reduce the access time, fluoroscopy time and postoperative decrease in haemoglobin level. No difference was found in the successful dilation rate, stone-free rate, transfusion rate or rate of complications between the OSD and serial dilation groups. The difference in the length of postoperative hospital stay was uncertain. OSD may be a better method of tract creation for PCNL.