We set out to investigate whether general anesthesia with low ventilation (LV, respiratory rate ≤8/min and tidal volume <500 ml) could reduce renal mobility and thereby facilitate improved retrograde intrarenal surgery (RIRS) compared to general anesthesia with standard ventilation (SV).
All 60 consecutive patients who presented for RIRS in our department from September 1, 2017 to December 31, 2017 were prospectively randomized 1:1 into one group that was selected to receive SV and another that received LV. Significant factors influencing the study endpoints considered fragmentation rate (FR), removal rate (RR), processing rate (PR) and operating rate (OR) were statistically analyzed for the whole group as well as for comparison by level of surgeon expertise.
Univariate analysis revealed that LV was a significant factor in improving all endpoints. Some endpoints were also affected by the stone's volume, number and density and the surgeon expertise. LV remained the single independent factor for FR, RR and PR in the multivariate analysis. LV significantly improved all four of the fellows' endpoints (p<0.05 for each) and positively influenced the expert's RR (p=0.04), PR (p=0.02) and OR (p=0.04). The performance gap between the fellows and the experts narrowed under LV. The end-tidal CO2 was significantly higher in the LV group (50 vs 36 mmHg; p<0.0001), however, without any clinical significance. The overall stone-free rate (97%) and complication rate (5%) were not significantly different between the two groups. The patient's anesthesia-related safety was not affected by the mode of ventilation as evidenced by no need to convert from LV to SV during the procedures.
LV during RIRS has a significant positive impact on the overall improvement of surgical performance and effectiveness. It does not negatively affect the patient's.
Journal of endourology. 2018 May 23 [Epub ahead of print]
Vasileios Kourmpetis, Snir Dekalo, Tomer Nir, Nadav Levy, Yuval Bar-Yosef, Avi Beri, Ofer Yossepowitch, Mario Sofer
Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Endourological Unit, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Division Of Anesthersia, Pain and Intensive care, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Division Of Anesthersia, Pain and Intensive care, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Sakler School of Medicine, Tel-Aviv University, Endourology Unit, Tel-Aviv, Israel ; .