Tubeless percutaneous nephrolithotomy: evaluation of minimal invasive exit strategies after percutaneous stone treatment

Mini-percutaneous nephrolithotomy vs flexible ureteroscopy for 1-2 cm lower pole renal stones: a randomised controlled trial

OBJECTIVE

To compare the safety and efficacy of flexible ureteroscopy (f-URS) and ambulatory tubeless mini-percutaneous nephrolithotomy (mini-PCNL) in the treatment of 1-2 cm lower calyceal renal stones.

PATIENTS AND METHODS

Patients who underwent f-URS and mini-PCNL for the treatment of 1-2 cm lower calyceal renal stones between October 2020 and November 2023 were evaluated in a randomised controlled trial. A total of 72 patients were included in the study. All patients underwent a computed tomography renal colic scan preoperatively, on postoperative Day 1 (POD 1), and at 3 months follow-up. We compared perioperative outcomes, including operative time and hospital stay. Additionally, we evaluated follow-up outcomes, such as the stone-free rate (SFR) and complications. All patients were discharged home on the same operative day.

RESULTS

There were no significant differences in preoperative baseline data between the two surgical groups. A significantly longer median operative time was reported in the mini-PCNL group (P = 0.04). The median hospital stay was 5 h and 4 h in the mini-PCNL and f-URS groups, respectively (P = 0.14). On POD 1, the SFR, defined as the absence of residual fragments measuring 0 cm, was 50% for mini-PCNL vs 11.1% for f-URS (P < 0.001). When a total cut-off of <4 cm was utilised, the SFR was 75% in the mini-PCNL group vs 22.2% in the f-URS cohort (P < 0.001). At 3 months follow-up, the SFR remained favourable for mini-PCNL at 72.2% vs 37.1% for f-URS (P = 0.003), with a cut-off of 0 cm, and it increased to 86.1% for mini-PCNL vs 65.7% for f-URS (P = 0.04) when a total cut-off of <4 cm was applied. There was no significant difference in postoperative complications between the two groups. Two patients (5.7%) in the f-URS group required re-treatment.

CONCLUSIONS

Ambulatory tubeless mini-PCNL and f-URS are effective treatment options for 1-2 cm lower calyceal renal stones. Both techniques have a comparable hospital stay and complication rates, with a significantly better SFR with mini-PCNL.

International Alliance of Urolithiasis (IAU) guidelines on the management of pediatric urolithiasis

The aim of this study was to construct the sixth in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis (IAU) that by providing a clinical framework for the management of pediatric patients with urolithiasis based on the best available published literature. All recommendations were summarized following a systematic review and assessment of literature in the PubMed database from January 1952 to December 2023. Each generated recommendation was graded using a modified GRADE methodology. Recommendations are agreed upon by Panel Members following review and discussion of the evidence. Guideline recommendations were developed that addressed the following topics: etiology, risk factors, clinical presentation and symptoms, diagnosis, conservative management, surgical interventions, prevention, and follow-up. Similarities in the treatment of primary stone episodes between children and adults, incorporating conservative management and advancements in technology for less invasive stone removal, are evident. Additionally, preventive strategies aiming to reduce recurrence rates, such as ensuring sufficient fluid intake, establishing well-planned dietary adjustments, and selective use pharmacologic therapies will also result in highly successful outcomes in pediatric stone patients. Depending on the severity of metabolic disorders and also anatomical abnormalities, a careful and close follow-up program should inevitably be planned in each pediatric patient to limit the risk of future recurrence rates.

Comparison of safety and efficacy of tubeless vs. conventional mini percutaneous nephrolithotomy in patients with Escherichia coli bacteriuria

To evaluate the safety and efficacy of tubeless percutaneous nephrolithotomy (PCNL) in patients with Escherichia coli (E. coli) bacteriuria. We conducted a retrospective review of 84 patients with E. coli bacteriuria who underwent PCNL. Patients were divided into two groups according to whether a nephrostomy tube is placed at the end of the procedure. Preoperative clinical data, surgical outcomes, and postoperative complications were compared. Then, regression analysis of factors predicting success rate of PCNL in patients with E. coli bacteriuria was performed. After PCNL, residual fragments ≤ 4 mm were considered as success. At baseline, the two groups were similar with regard to age, gender, BMI, underlying disease, hydronephrosis, stone characteristics, and urinalysis. Postoperative fever occurred in 1 patient (3.8%) in the tubeless PCNL group, and in 5 patients (8.6%) in the conventional PCNL group (p > 0.05). There were no significant differences in terms of successful rate, decrease in hemoglobin, pain scores, blood transfusion, and hospitalization expenses. However, the tubeless PCNL group had significantly shorter operative time (60 vs. 70 min, p = 0.033), indwelling time of catheter (2 vs. 4 days, p < 0.001), and hospital stays (3 vs. 5 days, p < 0.001) than the conventional PCNL group. In the analysis of factors predicting success, the stone diameter, stone burden, and operative time were associated with success rate of PCNL. It is safe and effective to perform tubeless PCNL in patients with E. coli bacteriuria. Compared to conventional PCNL, tubeless PCNL accelerates patient recovery and shortens hospital stays.

The global, prevalence, and risk factors of postoperative fever after percutaneous nephrolithotomy: A systematic review and meta-analysis

Objective

This study aimed to explore the global, prevalence, and risk factors of fever after percutaneous nephrolithotomy (PCNL) by conducting a systematic review and meta-analysis.

Methods

The high-sensitivity searching was conducted without time limitation until December 30, 2020 in Web of Sciences, Scopus, and PubMed based on inclusion and exclusion criteria.

Results

The prevalence rates of fever and sepsis among patient undergoing PCNL were estimated 9.5% (95% confidence interval [CI]: 9.3%-9.7%), and 4.5% (95% CI: 4.2%-4.8%), respectively. Nephrostomy tube was used in 9.96% (95% CI: 9.94%-9.97%) of patients. The mean preoperative white blood cells of patients were 6.401×109/L; 18.3% and 4.55% of patients were considered as the positive urinary culture and pyuria, respectively. About 20.4% of patients suffered from residual stones. The odds ratios (ORs) of fever in patients who suffering from diabetes mellitus, hydronephrosis, staghorn stones, and blood transfusion were 4.62 (95% CI: 2.95-7.26), 1.04 (95% CI: 0.81-1.34), 2.57 (95% CI: 0.93-7.11), and 2.65 (95% CI: 1.62-4.35), respectively. Patients who underwent PCNL in prone position were more likely to develop fever (OR: 1.23; 95% CI: 0.75-2.00) than patients in supine position.

Conclusion

The current study showed that patients who suffer from diabetes mellitus, hydronephrosis, staghorn stones, nephrostomy tube or double-J stent, blood transfusion, and also patients who underwent PCNL in prone position surgery are more likely to develop a postoperative fever after PCNL.

A randomized controlled study of ureteral stent extraction string on patient's quality of life and stent-related complications after percutaneous nephrolithotomy in the prone position

To demonstrate the Tianjin Institute of Urology (TJIU) technique to place and remove the ureteral stent with extraction string after percutaneous nephrolithotomy (PCNL). Additionally, we aim to compare the pain experienced during stent removal, quality of life during stent retention, and stent-related complications between patients with and without extraction string. 65 patients were included in the final analysis in the string group constructed by the TJIU technique and 66 patients in the conventional double-J ureteral stent (non-string) group. All patients underwent the surgery in a prone position under general anesthesia. They completed the Ureteral Stent Symptom Questionnaire (USSQ) on postoperative days (POD) 7, as well as before their ureteral stent was removed. The visual analogue scale (VAS) pain score (0-10) was completed immediately after the removal of the ureteral stent. Moreover, a specialized person was responsible for recording stent-related complications. All patients completed the USSQ on POD 7, and we did not find a difference in scores in each field. However, there was a significant difference in the "sex" domain before removing the ureteral stent (4.34 vs 3.23; p = 0.01). Notably, the use of extraction string after PCNL could decrease the pain associated with stent removal significantly (mean VAS scores 1.45 vs 2.76; p < 0.01). Extraction string did not increase the incidence of stent-related complications. We concluded that placing a ureteral stent with an extraction string after PCNL reduces the pain of ureteral stent removal without increasing complications such as accidental removal of the stent, febrile urinary tract infection (UTI).

Determinants of ureteral obstruction after percutaneous nephrolithotomy

BACKGROUND

Ureteral obstruction after percutaneous nephrolithotomy (PCNL) may require prolonged drainage with a nephrostomy tube (NT) or ureteral stent, but it is not well understood how and why this occurs. The goal of this study was to identify risk factors associated with postoperative ureteral obstruction to help guide drainage tube selection.

METHODS

Prospective data from adult patients enrolled in the Registry for Stones of the Kidney and Ureter (ReSKU) who underwent PCNL from 2016 to 2020 were used. Patients who had postoperative NTs with antegrade imaging-based flow assessment on postoperative day one (POD1) were included. Patients with transplanted kidneys or those without appropriate preoperative imaging were excluded. We assessed the association between patient demographics, stone characteristics, and intraoperative factors using POD1 antegrade flow, a proxy for ureteral patency, as the primary outcome. Stepwise selection was used to develop a multivariate logistic regression model controlling for BMI, stone location, stone burden, ipsilateral ureteroscopy (URS), access location, estimated blood loss, and operative time.

RESULTS

We analyzed 241 cases for this study; 204 (84.6%) had a visual clearance of stone. Antegrade flow on POD1 was absent in 76 cases (31.5%). A multivariate logistic regression model found that stones located anywhere other than in the renal pelvis (OR 2.63, 95% CI 1.29-5.53; p = 0.01), non-lower pole access (OR 2.81, 95% CI 1.42-5.74; p < 0.01), and concurrent ipsilateral URS (OR 2.17, 95% CI 1.02-4.65; p = 0.05) increased the likelihood of obstruction. BMI, pre-operative stone burden, EBL, and operative time did not affect antegrade flow outcomes.

CONCLUSION

Concurrent ipsilateral URS, absence of stones in the renal pelvis, and non-lower pole access are associated with increased likelihood of ureteral obstruction after PCNL. Access location appears to be the strongest predictor. Recognizing these risk factors can be helpful in guiding postoperative tube management.

Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy

PURPOSE OF REVIEW

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

RECENT FINDINGS

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal. Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.