Phase III Trial of Intravenous Mannitol Versus Placebo During Nephron-sparing Surgery: Post Hoc Analysis of 3-yr Outcomes

Intraoperative Intravenous Mannitol Administration Failed to Provide Added Value on Renal Functional Preservation After Partial Nephrectomy in Patients with Chronic Kidney Disease: A Matched Cohort Study

Background: Previous randomized-controlled trials have demonstrated that intraoperative intravenous mannitol administration shows no added value on renal functional preservation after partial nephrectomy (PN) in patients with normal renal function. However, the renoprotective effect of mannitol has not been fully evaluated in patients with preoperative chronic kidney disease (CKD). Materials and Methods: This was a retrospective cohort study with propensity score matching. Patients with a preoperative estimated glomerular filtration rate (eGFR) of <60 mL/minute/1.73 m² undergoing PN were enrolled in the study between January 2012 and December 2019 in Peking University First Hospital. Participants were divided into two groups: patients who received 25 g of mannitol (group M+) or not (group M-). The primary endpoint was the decreased rate of eGFR at the 6-month follow-up. Results: A total of 244 patients were included in the analysis. After propensity score matching, 80 patients remained in each group. The percentage of decrease from baseline eGFR at postoperative 6-month follow-up showed no difference between the two patient groups (median 11.1 [interquartile range 5.3-25.3] in group M+ vs 12.2 [4.7-21.3] in group M-, median difference -0.7 [95% confidence interval -4.6 to 3.1]; p = 0.704). Postoperative acute kidney injury, renal replacement therapy during hospitalization, postoperative complications, incidence of >20% decrease from baseline eGFR at 6 months, and dialysis at 6 months showed no difference between the two patient groups. Conclusions: A 25 g dose of mannitol administration during PN failed to provide added value on renal functional preservation in CKD patients.

Robotic-Assisted Partial Nephrectomy: Techniques to Improve Clinical Outcomes

PURPOSE OF REVIEW

To summarize current options available for robot-assisted partial nephrectomy RECENT FINDINGS: Partial nephrectomy (PN) is a standard treatment option for management of cT1 renal masses. It may be carried out by multiple approaches. Robot-assisted (RA) PN is one such option. The goal of treatment is both correct oncological (negative surgical margins) and functional (preservation of sufficient amount of renal parenchyma of the operated kidney) outcome. Appropriate outcomes depend on multiple factors. There are many, but among others tumor characteristics (size, location, i.e., tumor complexity), patient baseline renal function, patient comorbidities, and performance status etc. Based on all these, the surgeon adapts the intervention for each mass/patient by preoperative planning, absence/use/duration of warm or cold ischemia, perioperative imaging, resection technique adapted to tumor location and depth of invasion, use of hemostatics, type and degree of renal parenchymal closure and others details. Nephroprotective agents have not shown efficacy so far. It should not be forgotten that surgeon's experience plays a key role in the achievement of good results. Although multiple factors have a role in the RA partial nephrectomy, surgeon experience and adaptation of technique of intervention have the crucial role in the achievement of both functional and oncological results.

The use of mannitol in partial nephrectomy for renal function preservation: meta-analysis and systematic review of comparative studies

Objective:

We aimed to assess the effect and safety of mannitol use in partial nephrectomy for renal function preservation.

Methods:

A systematic literature search was performed. Randomised controlled trials and non-randomised controlled trials comparing with versus without mannitol use in partial nephrectomy were screened and evaluated according to Cochrane Collaboration recommendations. Outcomes assessed were percentage change from preoperative estimated glomerular filtration rate, estimated blood loss and complications. The standardised mean difference (SMD) and risk ratio (RR) with corresponding 95% confidence intervals were extrapolated. Effect estimates were pooled using the inverse variance method with a random-effects model. Subgroup analysis was performed according to study design and follow-up duration. Grading of recommendations, assessment, development and evaluations assessment was used to rate the quality of evidence.

Results:

A total of 1136 patients from two randomised controlled trials ( n=264) and six non-randomised controlled trials ( n=872) were included. The included randomised controlled trials had some concerns regarding a high risk of bias; while the non-randomised controlled trials were all retrospective studies with moderate to serious concern for risk of bias. Overall pooled effect estimates for short and long-term follow-up showed no significant differences between intervention groups for percentage change from preoperative estimated glomerular filtration rate (SMD 0.09, 95% confidence interval (CI) −0.11, 0.29; SMD −0.06, 95% CI −0.22, 0.06, respectively). Likewise, no between-group difference was noted for intraoperative blood loss and complication rates (SMD 0.05, 95% CI −0.08, 0.17; RR 1.07, 95% CI 0.6, 1.82, respectively).

Conclusion:

The pooled effect estimates from both randomised and non-randomised comparative studies illustrated no overall short-term or long-term advantage with mannitol use in partial nephrectomy for the preservation of estimated glomerular filtration rate. Likewise, no difference was noted for intraoperative blood loss or complication rates. However, to date there is only a very low to low quality of evidence available to extrapolate conclusions.

Level of evidence:

Very low to low

Examining Mannitol Use in Kidney Cancer Surgery: A Cautionary Tale of Extrapolated Surgical Data

Mannitol for renal protection during partial nephrectomy is common but unsupported by evidence from clinical trials. The impact of mannitol on renal physiology includes both beneficial and harmful effects. Current understanding of renal ischemia reperfusion injury suggests potentially targetable processes that have a lower potential risk.