Comparison of off-clamp partial nephrectomy and on-clamp partial nephrectomy: a systematic review and meta-analysis

To compare peri- and postoperative variables, surgical complications, oncological outcomes and renal outcomes of off-clamp partial nephrectomy (PN) and on-clamp PN.

A systematic search of the electronic databases, including MEDLINE, Embase and Cochrane Library, was performed. The pooled estimates of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, positive surgical margins and eGFR were calculated.

14 studies were included. There was no significant difference between off-clamp PN and on-clamp PN in terms of tumour size, operative time, estimated blood loss, length of stay, overall complications, transfusion rates, urinary leaks, and positive surgical margins. However, a non-statistically significant trend towards increased blood loss (p = 0.12) and transfusion rates (p = 0.07) in those undergoing off-clamp PN was noted. Off-clamp PN was associated with a significantly lower reduction in eGFR than on-clamp PN (standardised weighted mean difference 0.27, 95% CI 0.14, 0.40, p < 0.0001).

Off-clamp PN may be associated with improved long-term renal outcomes when compared to on-clamp PN with no difference in in peri- and postoperative variables, surgical complications and oncological outcomes. However, the meta-analysis was limited by the design of the underlying studies, and hence further work is necessary.