Ureteral access sheath-related injuries vs. post-operative infections. Is sheath insertion always needed? A prospective randomized study to understand the lights and shadows of this practice

Small tools, big impact and redefining endourology: the paradigm shift of ureteroscopy for large stones and percutaneous nephrolithotomy for small stones - a literature review

PURPOSE OF REVIEW

We aim to review the evolving paradigm in endourology, where technology has led us to manage small stones with ureteroscopy (URS) and large stones with miniaturized percutaneous nephrolithotomy (mPCNL) techniques. We analyse recent literature, their findings, emerging trends and newer technologies that are helping redefine modern day endourology in pushing these boundaries.

RECENT FINDINGS

A significant trend is the use of smaller devices to treat larger stones via ureteroscopy, and to treat smaller stones via percutaneous nephrolithotomy (PCNL). Improved laser technologies, smaller single use ureteroscopes and nephroscopes, suction access sheaths, all play a key role in this.The use of suction sheaths and vacuum assisted devices allows to control intrarenal pressure and help in reducing infectious and other complications whilst improving the stone-free rate (SFR). The treatment choice often depends on surgical expertise and available resources, guided by anatomical factors, stone composition and patient-specific considerations.

SUMMARY

The management of kidney stone disease has undergone a paradigm shift. While ureteroscopy is being done for larger renal stones, miniaturised PCNL is being done for small stones. This has been driven by a surge in technology, but a tailored and patient-centred approach is needed, and must be helped by guidelines and a multidisciplinary approach.

Utilization of Ureteral Access Sheath in Retrograde Intrarenal Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: This paper evaluates the efficacy and safety of ureteral access sheath (UAS) utilization in retrograde intrarenal surgery (RIRS). Materials and Methods: We searched PubMed, Embase, and the Cochrane Library up to 30 August 2023. The inclusion criteria comprised English-language original studies on RIRS with or without UAS in humans. The primary outcome was SFR, while the secondary outcomes included intraoperative and postoperative complications, the lengths of the operation and the hospitalization period, and the duration of the fluoroscopy. Subgroup analyses and a sensitivity analysis were performed. Publication bias was assessed using funnel plots and Egger's regression tests. Dichotomous variables were analyzed using odds ratios (ORs) with 95% confidence intervals (CIs), while mean differences (MDs) were employed for continuous variables. Results: We included 22 studies in our analysis. These spanned 2001 to 2023, involving 12,993 patients and 13,293 procedures. No significant difference in SFR was observed between the UAS and non-UAS groups (OR = 0.90, 95% CI 0.63-1.30, p = 0.59). Intraoperative (OR = 1.13, 95% CI 0.75-1.69, p = 0.5) and postoperative complications (OR = 1.29, 95% CI 0.89-1.87, p = 0.18) did not significantly differ between the groups. UAS usage increased operation times (MD = 8.30, 95% CI 2.51-14.10, p = 0.005) and fluoroscopy times (MD = 5.73, 95% CI 4.55-6.90, p < 0.001). No publication bias was detected for any outcome. Conclusions: In RIRS, UAS usage did not significantly affect SFR, complications, or hospitalization time. However, it increased operation time and fluoroscopy time. Routine UAS usage is not supported, and decisions should be patient-specific. Further studies with larger sample sizes and standardized assessments are needed to refine UAS utilization in RIRS.

Post-Ureteroscopic Lesion Scale to determine ureteral wall damage, not so easy to employ

OBJECTIVE

To analyze the level of agreement of the Post-Ureteroscopy Lesion Scale (PULS) and the consequences on its application in clinical practice with more reliable statistical data than the one used in the original work.

METHODS

14 URS and 14 micro-URS were performed in 14 female porcine model. All the procedures were video recorded and an anatomopathological analysis was performed in each ureter. Sixteen urologists (9 endourologists and 7 general urologists) and 4 residents evaluated the ureteral lesions according to the PULS, with degrees 0, 1 and ≥2. The agreement was calculated with percentages, Kendall's W coefficient and the indicators Fleiss' Kappa and Krippendorff's Alpha, while the inter-rater agreement was calculated with Spearman's correlation and Cohen's Kappa.

RESULTS

The percent of agreement was 11.1%. The coefficients were likewise classified as low or very low, with the greatest agreement found among the inexperienced. Also, 50% of the raters did not agree with the rest.

CONCLUSIONS

The low inter-rater agreement, the specificity of the PULS and the clinical-pathological correlation suggests that this scale is not simple, and probably has a long learning curve.

The Effect of Ureteral Access Sheath Use/Caliber Change on Outcomes of Retrograde Intrarenal Surgery, Short-Term Kidney Functions, Radiation Exposure, Ureteroscope Lifetime, and Factors Predicting Insertion Failure: A RIRSearch Study

Background: The aim of this study was (1) to explore effect of ureteral access sheath (UAS) use on primary retrograde intrarenal surgery (RIRS) outcomes, short-term kidney functions, radiation exposure, and ureteroscope lifetime (URS-LT) and (2) to reveal factors that predict UAS insertion failure. Materials and Methods: Patients (n = 1318) who underwent RIRS without UAS (Group 1), those who had operation with a <11-13 Fr (Group 2), and those with a ≥11-13 Fr UAS were matched (1:1:2) and compared. Stone-free rate (SFR), intra- and postoperative complications, acute kidney injury (AKI), fluoroscopy time, URS-LT, and UAS insertion failure were the outcomes. Results: SFR, which was highest in Group 3 (75%, 71% and 87.3%, respectively; P = .001), was significantly associated with use of ≥11-13 Fr (odds ratio [OR]: 4.2, P < .001), but was not with use of <11-13 Fr UAS (OR: 1.3, P = .3). Group 3 had less need for auxiliary procedure (15%, 16%, and 7.4%, respectively; P = .03). Five percent of patients had a risk of AKI, but only 0.3% developed AKI. Although UAS use was protective against creatinine increase (OR: 0.65, P = .02), increased risk of AKI was only associated with female gender (OR: 5.5, P < .001). Fluroscopy times were 5, 15, and 87 sn, respectively (P < .001). Short URS-LT was strongly associated with high frequency of lower calix stones (r = -0.94, P = .005), but URS-LT was not correlated with sheathless case rate (r = 0.59, P = .22). UAS insertion success in first attempt was more likely in younger (OR: 0.99, P = .03), hydronephrotic (OR: 3.4, P < .001), and female cases (OR: 1.5, P = .008). But absolute UAS insertion failure was associated with female gender (OR: 2.7, P = .017). Conclusions: Not any UAS use but a higher caliber UAS use may improve SFR and protect against AKI after RIRS. Although UAS insertion failure is seen mostly in men, it may be more challenging in women owing to less efficacy of preoperative Double-J stent.

Does gender influence retrograde intrarenal surgery (RIRS) outcomes? Data from the Flexible Ureteroscopy Outcomes Registry (FLEXOR)

INTRODUCTION AND OBJECTIVES

As well established flexible ureteroscopy (RIRS). There is still no evidence if gender can have any influence on the outcomes and complication when performing. This study aims to evaluate the role that gender has in performing flexible ureteroscopy from a large series of patients.

METHODS

This study retrospectively analyzed patients who underwent RIRS for renal stones from January 2018 to August 2021 within the multicentric FLEXOR registry. Demographics, stone characteristics, perioperative findings, results and complications were analyzed and compared between gender groups.

RESULTS

A total of 6669 patients were included, 66.1% were male and 33.9% were female. Stone characteristics was comparable between groups. Female patients had significant higher fever and positive urine culture rates (12% vs. 8% and 37% vs. 34%). Also, females had a slight longer hospital stay (3.8 vs. 3.5 days; P < 0.001) and more residual fragments after the procedure (23.03% vs. 20.97 (P = 0.032). Overall complications were slightly significantly higher in women (15.74% vs. 14% (P = 0.042)) mainly at the expense of fever rates (6.9% vs. 5.7%) whereas the risk of sepsis was similar in both groups. A multivariate analysis showed that larger stone size, multiple and lower pole stones seem to have a negative impact in the incidence of residual stones and complications.

CONCLUSION

Our real life global study reflects that female gender may have a correlation with a slightly increased residual fragment rate and overall low grade complications. However, women can safely be treated with RIRS with no increased the rate of sepsis with appropriate care.

Is It a Good Strategy to Proceed a Retrograde Intrarenal Surgery Session Sheathless After Ureteral Access Sheath Insertion Failure? A RIRSearch Study

Objectives: To complement our previous findings regarding effect of ureteral access sheath (UAS) use, we checked RIRSearch database for patients who operated without using UAS. The aim of the study was to understand these new data better by comparing outcomes of retrograde intrarenal surgery (RIRS) that continued sheathless after a failed UAS insertion vs those planned and completed sheathless. Materials and Methods: Data of 195 patients who underwent sheathless RIRS for kidney and/or ureteral stones between 2011 and 2021 were retrieved from the database. Patients divided into two groups: cases who were planned and completed sheathless (n = 110, Group 1) and those who proceeded without UAS after insertion failure (n = 85, Group 2). After propensity score matching (PSM), each group consisted of 76 patients. Results: After PSM, stone-free rate for Group 1 (90.8%) was significantly higher than stone-free rate of Group 2 (76.3%) in sheathless RIRS (p = 0.02). Also postoperative complication rate was significantly lower in Group 1 (10.5%) than in Group 2 (27.6%) (p = 0.007). In Group 2, median operating time was longer (60 minutes, interquartile range [IQR]: 40-80) and more unplanned auxilliary procedure (22.4%) was needed than Group 1 (45 minutes, IQR: 40-50 and 3.9%) (both p = 0.001). Stone burden (odds ratio [OR]: 1.002, p = 0.019) and stone density (OR: 1.002, p = 0.003) were associated with high risk of residual stones after RIRS. Higher hydronephrosis grades were associated with increased stone-free rates (OR: 0.588 for residual stone risk, p = 0.024). Cases who completed sheathless by dusting all available stones, as planned preoperatively, were more likely to have stone-free status after RIRS than those who proceeded sheathless after UAS insertion failure (OR: 2.645, p = 0.024). Conclusions: Operation course after UAS insertion failure may be more challenging. In cases who performed without using UAS, surgeons who proceed with procedure sheathless after UAS insertion failure may more frequently run into complications and may fail achieving stone-free status compared with sheathless-planned cases.

Impact of a delayed presentation to the emergency department for acute renal colic on biochemical and clinical outcomes

INTRODUCTION AND OBJECTIVE

To verify the impact of delay on biochemical and clinical outcomes for patients presenting to the emergency department (ED) with acute renal colic.

MATERIALS AND METHODS

Data were retrospectively collected from three institutions of two European countries between 01 January and 30 April 2020. Patients who presented to the ED with unilateral or bilateral renal colic caused by urolithiasis confirmed by imaging tests during the study period were included. A presentation after 24 h since the onset of symptoms was considered a delay. Patients presenting before 24 h from the symptom onset were included in Group A, while the patients presenting after 24 h in Group B. Clinical and biochemical parameters and management were compared.

RESULTS

A total of 397 patients who presented to ED with confirmed urolithiasis were analyzed (Group A, n = 199; Group B, n = 198. The median (IQR) delay in presentation was 2 days (1,5-4). At presentation, no statistically significant differences were found amongst the two groups of patients regarding presenting symptoms such as fever and flank pain, and the median serum levels of creatinine, C reactive protein and white blood cells. No differences were found in terms of conservative or operative management.

CONCLUSION

Delay in consultation >24 h is not associated with worsening biochemical parameters and clinical outcomes. Most patients with acute loin pain do not necessarily need urgent attendance to the ED and may be managed in the outpatients.

Ureteral Access Sheaths and Its Use in the Future: A Comprehensive Update Based on a Literature Review

Ureteral access sheaths (UASs) are part of urologist’s armamentarium when performing retrograde intrarenal surgery (RIRS). Recently, the world of RIRS has changed dramatically with the development of three game-changers: thulium fiber laser (TFL), smaller size single use digital flexible ureterosopes and intraoperative intrarenal pressure (IRP) measurement devices. We aimed to clarify the impact of UASs on IRP, complications and SFRs and put its indications in perspective of these three major technological improvements. A systematic review of the literature using the Medline, Scopus and Web of Science databases was performed by two authors and relevant studies were selected according to PRISMA guidelines. Recent studies showed that using a UAS lowers IRP and intrarenal temperature by increasing irrigation outflow during RIRS. Data on the impact of a UAS on SFRs, postoperative pain, risk of infectious complications, risk of ureteral strictures and risk of bladder recurrence of urothelial carcinoma after diagnostic RIRS were inconclusive. Prestenting for at least one week resulted in ureteral enlargement, while the influence of pre-operative administration of alpha-blockers was unclear. Since TFL, smaller single use digital ureteroscopes and devices with integrated pressure-measuring and aspiration technology seemed to increase SFRs and decrease pressure and temperature related complications, indications on the use of a UAS may decrease in the near future.