Risk factors for hemorrhage requiring embolization after percutaneous nephrolithotomy

Severe bleeding in patients following "tubeless" percutaneous nephrolithotomy: Predictors of angioembolization

INTRODUCTION

Percutaneous nephrolithotomy (PCNL) is a widely used procedure for treating renal calculi. Advanced techniques have improved outcomes, but hemorrhage remains a significant complication. While most cases of hemorrhagic complications are typically managed conservatively, few cases necessitate interventions like angioembolization (AE). The purpose of this study is to identify risk factors closely associated with severe bleeding post-PCNL requiring AE and to assess if these factors can independently predict the type of lesion [arteriovenous fistula (AVF) vs pseudoaneurysm (PA)].

MATERIALS AND METHOD

A retrospective analysis was conducted on 119 patients who underwent "tubeless" PCNL and experienced severe bleeding between January 2018 and December 2023. The study reviewed demographic characteristics, stone characteristics, perioperative factors, and adverse events. The chi-square test and Fisher's exact test were used for univariate analysis. Logistic regression analysis was used in binomial analysis with a value of p < 0.05 considered statistically significant.

RESULTS

Out of 119 patients, 51 required AE. Elevated preoperative serum creatinine levels (>1.5 mg/dl) [p = 0.01], upper pole access [p = 0.008], and a larger access sheath size (standard PCNL vs mini-PCNL) [p ⩽ 0.001] were found to be significantly associated with AE. Logistic regression analysis revealed standard PCNL was significantly associated with post-PCNL bleeding requiring AE (odds ratio [OR]: 50, 95% confidence interval [CI]: 6.529-382.90, p ⩽ 0.001). Stone size and co-morbidities showed no significant association with AE. The average duration of presentation of symptoms post PCNL was 13.6 days. Most patients underwent coiling for AE, with a clinical success rate of 94%.

CONCLUSION

Elevated serum creatinine levels, upper pole access, and tract size >24 Fr are more prone to post-tubeless PCNL severe bleeding, which requires renal AE. The findings suggest that early angiography and possible AE should be considered for at-risk patients. In the future, these predictors may be integrated into predictive models to improve patient risk stratification.

Arteriovenous Fistula: The Case of a Rare Complication after Minimal Percutaneous Nephrostomy and Brief Review

Percutaneous renal surgery, although much less invasive than other procedures, is subject to several complications, which can occur at any time during the course of treatment, starting from the performance of the minimal nephrostomy procedure. We present an extremely rare vascular complication of percutaneous nephrostomy represented by arteriovenous fistula that occurred in a 24-year-old patient known to have right ureteropelvic junction obstruction operated with the absence of double-J catheter permeability and grade II-III hydronephrosis for which minimal percutaneous nephrostomy was urgently fitted. The arteriovenous fistula was resolved by supraselective artery embolization.

A rare case report of renal vein embolization after failed selective angioembolization to treat delayed complication of percutaneous nephrolithotomy

INTRODUCTION

Percutaneous nephrolithotomy (PCNL) has been considered the standard procedure for renal caliculi for its safety, shorter operative time, and cost-effectivity. Despite being minimally invasive, rare complications may still occur. This case presented a rare case of renal venous pseudoaneurysm after PCNL.

PRESENTATION OF CASE

A 34-year-old male was diagnosed with left lower calyx renal stone sized 14x13x8 mm with 388-571 Hounsfield Unit (HU). He underwent left mini PCNL with standard protocol. However, on two-weeks follow-up, gross haematuria was presented on emergency department admission. Patient underwent two times cystoscopy and blood clot evacuation. Postoperative contrast-enhanced CT showed saccular lesion sized 6.7 mm × 4.8 mm in the interlobar vein of left kidneys' lower pole. Patient was then consulted to Cardiothoracic-Vascular division, and undergone selective angiography and left renal artery embolization-coiling (VortX Diamond-18). Complaints and haemoglobin decline persists; thus, another attempt of embolization was performed with a different approach. Follow-up arteriography and venography showed complete obliteration of the aneurysm sac, followed by cessation of symptoms. This study is reported in line with SCARE criteria.

DISCUSSION

This is a rare case where a second embolization attempt (specifically via vein) was needed to overcome PCNL postoperative complication. Reviewing vascular complications risk factors after PCNL is crucial. This case report suggests complication management could be handled appropriately through procedures of selective angiography and embolization.

CONCLUSION

Coil embolization targeting the vein is a potentially effective and safe for selective cases of renal vein pseudoaneurysm. This case shows the importance of multidisciplinary approach and collaboration for better patient management.

Is it Safe to Continue Aspirin in Patients Undergoing Percutaneous Nephrolithotomy?

OBJECTIVE

To evaluate peri-operative outcomes in patients on chronic aspirin therapy undergoing percutaneous nephrolithotomy (PCNL), with and without discontinuation of aspirin. Anti-coagulation and anti-platelet therapy are contraindications for PCNL per American Urological Association guidelines due to bleeding risk. However, there is potentially increased cardiovascular risk with peri-procedural aspirin withdrawal.

METHODS

Patients on chronic aspirin undergoing PCNL between January 2014 and May 2019 were retrospectively reviewed and stratified by continued or discontinued aspirin >5 days preoperatively. Hematologic complications, transfusions, and thrombotic complications were assessed with logistic regression model.

RESULTS

Three hundred twenty-five patients on chronic aspirin therapy underwent PCNL-85 continued and 240 discontinued aspirin. There were no significant differences in hemoglobin change, estimated blood loss, transfusions, creatinine change, thrombotic complications, 30-days re-admissions, complications, or 30-day emergency department visits. Patients who continued aspirin had longer length of stay (1.6 vs 1.9 days, P = .03). American Society of Anesthesiologists (ASA) score of 3 (OR 3.2, P = .02, 95% confidence intervals (CI) [1.2-8.4]), ASA score of 4 (OR 4.0, P = .02, 95% CI [1.2-13.1]), Black race, and previous smoking (OR 2.1, P = .02, 95% CI [1.1-3.9]) was associated with continued aspirin. Body mass index ≥30 was associated with aspirin discontinuation (OR 0.9, P = .004, 95% CI [0.9-1.0]). Increased postoperative hematologic complications were associated with additional anticoagulation medication (OR 2.9, P = .04, 95% CI [1.0-4.4]).

CONCLUSION

Continued aspirin use did not increase in postoperative complications in patients undergoing PCNL. Patients who are on additional anticoagulation medication are at risk of hematologic complications.

Predictive factors for percutaneous nephrolithotomy bleeding risks

Objective

This study aimed to identify predictive factors for percutaneous nephrolithotomy (PCNL) bleeding risks. With better risk stratification, bleeding in high-risk patient can be anticipated and facilitates early identification.

Methods

A prospective observational study of PCNL performed at our institution was done. All adults with radio-opaque renal stones planned for PCNL were included except those with coagulopathy, planned for additional procedures. Factors including gender, co-morbidities, body mass index, stone burden, puncture site, tract dilatation size, operative position, surgeon's seniority, and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin (Hb) deficiency.

Results

Overall, 4.86% patients (n=7) received packed cells transfusion. The mean estimated Hb deficiency was 1.3 (range 0-6.5) g/dL and the median was 1.0 g/dL. Stepwise multivariate regression analysis revealed that absence of hypertension (p=0.024), puncture site (p=0.027), and operative duration (p=0.023) were significantly associated with higher estimated Hb deficiency. However, the effect sizes are rather small with partial eta-squared of 0.037, 0.066, and 0.038, respectively. Observed power obtained was 0.621, 0.722, and 0.625, respectively. Other factors studied did not correlate with Hb difference.

Conclusion

Hypertension, puncture site, and operative duration have significant impact on estimated Hb deficiency during PCNL. However, the effect size is rather small despite adequate study power obtained. Nonetheless, operative position (supine or prone), puncture number, or tract dilatation size did not correlate with Hb difference. The mainstay of reducing bleeding in PCNL is still meticulous operative technique. Our study findings also suggest that PCNL can be safely done by urology trainees under supervision in suitably selected patient, without increasing risk of bleeding.

Predictive factors of delayed bleeding after percutaneous nephrolithotomy requiring angioembolization

Objectives

To investigate the predictive factors of delayed post-percutaneous nephrolithotomy (PCNL) haemorrhage because of arteriovenous fistula (AVF) or pseudoaneurysm (PA) and compare the factors between AVF and PA.

Patients and methods

This is a case-control study with a case-to-control ratio of 1:3. Out of 5077 patients who underwent PCNL from April 2015 to April 2018 in three different teaching hospitals, 113 had post-PCNL haemorrhages because of AVF and/or PA. Seventy-two patients met the inclusion criteria and entered the study as cases, while 216 patients without any postoperative complications were selected as controls.

Results

Of all 72 studied patients with complications after PCNL, 35 (48.6%) had AVF, and the rest had PA. The regression model revealed that a history of diabetes (odds ratio [OR]: 2.799, 95% confidence interval [CI]: 1.392-5.630, p-value = 0.004) and renal anomalies (OR: 2.929, 95% CI: 1.108-7.744, p-value = 0.03) were associated with developing delayed post-PCNL haemorrhage. However, no differences were seen between AVF and PA regarding selected variables (p-value > 0.05).

Conclusion

History of diabetes and renal anomalies were predictive factors for delayed post-PCNL haemorrhage, but no predictive factors were found to differentiate PA and AVF from one another.

Risk factor analysis for infection and bleeding after lateral decubitus percutaneous nephrolithotomy

This study aimed to explore the risk factors for infection and bleeding after lateral decubitus percutaneous nephrolithotomy procedures to prevent their occurrence and improve surgical outcomes. A retrospective analysis was conducted on 356 patients who underwent lateral decubitus percutaneous nephrolithotomy for the treatment of kidney stones and upper ureteral stones from January 2015 to August 2022. Among them, 290 patients had complete clinical data. General clinical data, perioperative data, and stone characteristics were collected for each patient. Univariate and multivariate logistic regression analyses were performed to identify risk factors for infection and bleeding after lateral decubitus percutaneous nephrolithotomy. The postoperative infection rate after lateral decubitus percutaneous nephrolithotomy was 19.31%, and the postoperative bleeding rate was 12.07%. Independent risk factors for postoperative infection were multiple stones (P < .001), stone size (P < .001), and stone co-infection (P = .012). Independent risk factors for postoperative bleeding were multiple stones (P = .008) and stone size (P = .014). Multiple stones, stone size, and stone co-infection are independent risk factors for postoperative infection after lateral decubitus percutaneous nephrolithotomy. Multiple stones and stone size are independent risk factors for postoperative bleeding after lateral decubitus percutaneous nephrolithotomy.

Renal Pseudoaneurysm with Associated Arteriovenous Fistula as a Cause of Delayed Bleeding after Percutaneous Nephrolithotomy: A Case Report and Current Literature Review

Background

Pseudoaneurysm (PA) with associated arteriovenous fistula (AVF) is a rare delayed bleeding complication, occurring in less than 1% of patients after percutaneous nephrolithotomy (PNL). Case presentation. A 54-year-old man underwent PNL on February 28, 2023, for a large renal calculus in the right kidney lower pole, with postoperative delayed bleeding: macroscopic hematuria and bladder clot retention after 3 weeks. An iatrogenic PA and AVF were diagnosed after the failure of conservative measures. The patient was successfully treated with superselective angioembolization (SAE) under local anesthesia.

Conclusion

Late hemorrhagic complications after PNL can be severe. Rapid identification of a renal PA and AVF with SAE has a high success rate and low complication rate, avoiding prolonged hospitalization time and major renal surgery for this patient.

Antegrade Percutaneous Retrieval of Upward Migrated Double-J Stent in Very Small Size Pediatric Patients Under Ultrasonic Guide

Purpose: To evaluate the safety of antegrade percutaneous retrieval migrated ureteral stent in very small size pediatric patients with ultramini instruments under ultrasonography guide. Materials and Methods: A total number of 10 out of 115 patients who were referred to our center with upward migrated Double-J (DJ) were candidates for antegrade approach from 2017 to 2020. The pyelocalyceal system was punctured in a prone position by using an 18-gauge disposable needle with Chiba tip and visualization of the upper tract by 3.5 MHz ultrasonic guidance. Then 0.038-inch J tipped guide wire was passed through the needle and the tract was dilated up to 6F under ultrasonographic guide. The 8F access sheath was positioned over the 6F dilator. The semirigid 6F ureteroscope was introduced through the sheath and DJ was removed with a grasper. Results: The mean age was 11.4 ± 5.48 months. The mean time from the previous surgery to DJ removal procedure was 6.4 ± 0.84 weeks. The mean operation time was 11.7 ± 1.76 minutes. All the patients were discharged from the hospital within the 1st day. There were no serious complications (grade 3, 4, or 5) according to Clavien-Dindo classification. Conclusion: The antegrade retrieval of upward migrated DJ with ultramini instrument under ultrasonographic guidance in failed cases of retrograde approach is a safe and effective approach in very small size pediatric patients.

Hemorrhagic complicationes after percutaneous nephrolithotomy: The importance of an early endovascular management

INTRODUCTION AND OBJECTIVES

Hemorrhage due to arteriovenous fistula (AVF) or pseudoaneurysm (PA) is a rare complication after percutaneous nephrolithotomy (PCNL). The objective of this study is to evaluate hemorrhagic complications (HC) after PCNL and the results of their endovascular treatment.

MATERIALS AND METHODS

Between May 2009 and December 2019, 1335 PCNL were performed in our center for kidney stone disease. We analyzed the incidence of early and late HC, their management, the need for subsequent embolization, as well as clinical and analytical data of these patients.

RESULTS

A total of 59 (4.4%) patients presented HC. Bleeding was managed with arteriography and selective embolization (ASE). Perirenal hematoma was seen in 38 patients (64%). Regarding angiographic findings, there were 32 (54%) PA, 8 (14%) AVF, 4 (7%) extravasations due to vascular laceration and 15 (25%) PA combined with AVF. In one case, 3 procedures were required to control the bleeding. In 30 patients (51%) blood transfusions were not necessary, while in 29 (49%), a mean of 1.3 units were transfused. Median follow-up was 24 ± 21 months. Mean time interval between PCNL and ASE was 7.3 ± 4.9 days. A total of 24 (41%) patients were readmitted after discharge due to late HC requiring ASE. Delay between readmission and ASE was 4.8 ± 4.6 h in average.

CONCLUSION

Early and late HC after PCNL can be severe. Rapid identification and treatment with ASE is an effective and minimally invasive and avoids multiple blood transfusions which in many cases constitute an insufficient treatment.

Hemorrhagic complicationes after percutaneous nephrolithotomy: The importance of an early endovascular management

INTRODUCTION AND OBJECTIVES

Hemorrhage due to arteriovenous fistula (AVF) or pseudoaneurysm (PA) is a rare complication after percutaneous nephrolithotomy (PCNL). The objective of this study is to evaluate hemorrhagic complications (HC) after PCNL and the results of their endovascular treatment.

MATERIALS AND METHODS

Between May 2009 and December 2019, 1335 PCNL were performed in our center for kidney stone disease. We analyzed the incidence of early and late HC, their management, the need for subsequent embolization, as well as clinical and analytical data of these patients.

RESULTS

A total of 59 (4.4%) patients presented HC. Bleeding was managed with arteriography and selective embolization (ASE). Perirenal hematoma was seen in 38 patients (64%). Regarding angiographic findings, there were 32 (54%) PA, 8 (14%) AVF, 4 (7%) extravasations due to vascular laceration and 15 (25%) PA combined with AVF. In one case, 3 procedures were required to control the bleeding. In 30 patients (51%) blood transfusions were not necessary, while in 29 (49%), a mean of 1.3 units were transfused. Median follow-up was 24±21 months. Mean time interval between PCNL and ASE was 7.3±4.9 days. A total of 24 (41%) patients were readmitted after discharge due to late HC requiring ASE. Delay between readmission and ASE was 4.8±4.6hours in average.

CONCLUSION

Early and late HC after PCNL can be severe. Rapid identification and treatment with ASE is an effective and minimally invasive and avoids multiple blood transfusions which in many cases constitute an insufficient treatment.

The Outcomes of Minimally Invasive Percutaneous Nephrolithotomy with Different Access Sizes for the Single Renal Stone ≤25 mm: A Randomized Prospective Study

OBJECTIVES

The aim of this study was to provide a randomized controlled trial comparing the outcomes of different access sizes used in the solo ultrasonic-guided minimally invasive percutaneous nephrolithotomy (mini-PCNL).

METHODS

From January 2018 to December 2019, a total of 160 cases with single renal stones of <25 mm were randomized to undergo mini-PCNLs with Fr16, Fr18, Fr20, or Fr22 accesses. All accesses were established with the axis of the target calyx as the marker for puncture location and then expanded to the desired size. Hemoglobin reduction, operative time, stone-free rate, complications, etc., were all recorded and assessed.

RESULTS

The demographic data were similar, and there were no significantly intergroup differences in stone-free rate, complications, and hospital stay time. The hemoglobin reduction was comparable and was 0.9 ± 0.6, 0.9 ± 0.7, 1.0 ± 0.5, and 1.1 ± 0.7 g/dL for the groups Fr16, Fr18, Fr20, and Fr22, respectively. The operative time was 53.4 ± 14.5, 48.5 ± 15.2, 42.8 ± 13.3, and 43.3 ± 13.1 min for the 4 groups, which decreased significantly from group Fr16 to Fr20, but there was no significant difference between Fr20 and Fr22 groups.

CONCLUSIONS

The axis of target calyx is a reliable marker for establishment of percutaneous renal access under ultrasonic guidance. The surgical outcomes of different access sizes were comparable, but the operation time was significantly shortened with the increase of size. However, Fr22 was not more efficient than Fr20.

Percutaneous Endoscopic Treatment of Complicated Delayed Bleeding Postpercutaneous Nephrolithotomy: A Novel Suggestion

Background: Delayed bleeding after percutaneous nephrolithotomy (PCNL), which may occur within the first 3 weeks postoperatively, is a life-threatening complication that may result from arteriovenous fistula and arterial pseudoaneurysm. Angioembolization is the standard treatment when these patients develop hemodynamic instability despite conservative measures. Contrast hypersensitivity and renal insufficiency, however, contraindicate angiogram and subsequent embolization; in these patients, alternative methods such as the one described in this study may help in resolving the renal hemorrhage. Case Presentation: In this case series, we report the effective management of post-PCNL hemorrhage with nephroscopy and nephrostomy and drainage and tamponade because angioembolization was not feasible. Conclusion: Delayed bleeding after PCNL may be managed conservatively with nephrostomy drainage and tamponade when angioembolization is not feasible.

[Interventional treatment of hemorrhage after percutaneous nephrolithotomy]

OBJECTIVE

To evaluate the effectiveness of super-selective renal artery embolization in treatment of post-percutaneous nephrolithotomy bleeding, and to analyse the causes of failure embolization.

METHODS

In the study, 65 post-percutaneous nephrolithotomy patients with severe renal bleeding and hemodynamic instability were treated by super-selective renal artery embolization. First of all, we performed selective renal arteriography. After clarifying the location of the bleeding, superselective intubation of the injured vessel with a microcatheter was carried out. Then the injured vessel was embolized with Tornado micro-coil. When complete embolization was not achieved with micro-coil, a small amount of gelatin sponge particles were added. If there was no positive finding of the beginning selective renal arteriography, the following measures could be taken to prevent missing lesions: (1) Abdominal aorta angiography was performed to determine whether there were anatomical variations, such as accessory renal arteries or multiple renal arteries; (2) Ultra-selective intubation angiography next to the nephrostomy tube path was performed; (3) Renal arteriography was repeated; (4) Renal arteriography after removing the nephrostomy tube while retaining the puncture channel. We evaluated the different angiographic findings and analysed the causes of embolization failure.

RESULTS

Bleeding was successfully controled in 60 patients (62 kidneys) whose renal arteriography was postive. Positive findings included: pseudoaneurysm formation, patchy contrast extravasation, pseudoaneurysm combined with arteriovenous fistula, contrast agent entering the collection system, extravascular perinephric leakage of contrast. After first embolization, bleeding was controled in 53 patients (55 kidneys). The success rate after the first and second embolization was 88.7% and 96.7% respectively. The second session was required because of failure to demonstrate bleeding arteries during the first session (4 patients, 57.1%) and recurrent hemorrhage of the embolized injured arteries (2 patients, 28.6%). In 5 patients with no positive findings, after conservative treatment, hematuria disappeared. All the patients were followed up for 3, 6, and 12 months after embolization, and no hematuria occurred again, and no sustained and serious renal insufficiency.

CONCLUSION

Super-selective renal artery embolization is an effective treatment for post percutaneous nephrolithotomy bleeding. The main cause of failure is omitting of injured arteries during renal arteriography. Renal artery branch injury has various manifestations. Attention should paid to the anatomical variation of the renal artery, and patient and meticulous superselective intubation angiography is the key to avoiding missing the lesion and improving the success rate of embolization.

[Interventional treatment of hemorrhage after percutaneous nephrolithotomy]

OBJECTIVE

To evaluate the effectiveness of super-selective renal artery embolization in treatment of post-percutaneous nephrolithotomy bleeding, and to analyse the causes of failure embolization.

METHODS

In the study, 65 post-percutaneous nephrolithotomy patients with severe renal bleeding and hemodynamic instability were treated by super-selective renal artery embolization. First of all, we performed selective renal arteriography. After clarifying the location of the bleeding, superselective intubation of the injured vessel with a microcatheter was carried out. Then the injured vessel was embolized with Tornado micro-coil. When complete embolization was not achieved with micro-coil, a small amount of gelatin sponge particles were added. If there was no positive finding of the beginning selective renal arteriography, the following measures could be taken to prevent missing lesions: (1) Abdominal aorta angiography was performed to determine whether there were anatomical variations, such as accessory renal arteries or multiple renal arteries; (2) Ultra-selective intubation angiography next to the nephrostomy tube path was performed; (3) Renal arteriography was repeated; (4) Renal arteriography after removing the nephrostomy tube while retaining the puncture channel. We evaluated the different angiographic findings and analysed the causes of embolization failure.

RESULTS

Bleeding was successfully controled in 60 patients (62 kidneys) whose renal arteriography was postive. Positive findings included: pseudoaneurysm formation, patchy contrast extravasation, pseudoaneurysm combined with arteriovenous fistula, contrast agent entering the collection system, extravascular perinephric leakage of contrast. After first embolization, bleeding was controled in 53 patients (55 kidneys). The success rate after the first and second embolization was 88.7% and 96.7% respectively. The second session was required because of failure to demonstrate bleeding arteries during the first session (4 patients, 57.1%) and recurrent hemorrhage of the embolized injured arteries (2 patients, 28.6%). In 5 patients with no positive findings, after conservative treatment, hematuria disappeared. All the patients were followed up for 3, 6, and 12 months after embolization, and no hematuria occurred again, and no sustained and serious renal insufficiency.

CONCLUSION

Super-selective renal artery embolization is an effective treatment for post percutaneous nephrolithotomy bleeding. The main cause of failure is omitting of injured arteries during renal arteriography. Renal artery branch injury has various manifestations. Attention should paid to the anatomical variation of the renal artery, and patient and meticulous superselective intubation angiography is the key to avoiding missing the lesion and improving the success rate of embolization.

Enhanced super-mini-PCNL (eSMP): low renal pelvic pressure and high stone removal efficiency in a prospective randomized controlled trial

OBJECTIVE

In the present prospective randomized controlled trial (RCT), enhanced-SMP (eSMP) and conventional Chinese mini-PCNL (mPCNL) were compared to test the low renal pelvic pressure (RPP) and high stone removal efficiency in eSMP.

MATERIALS AND METHODS

Hundred patients with 2-5 cm renal calculus were enrolled. Renal pelvic pressure, operation time, lithotripsy time, removed stone volume, and complications were compared between eSMP and mPCNL statistically.

RESULTS

There was no significant difference in removed stone volume between mPCNL and eSMP (8.09 ± 3.36 vs. 7.88 ± 3.07 mm³, t = 0.320, p = 0.750), lithotripsy time in mPCNL was longer than eSMP (49.6 ± 19.5 vs. 34.9 ± 14.2 min, t = 4.152, p < 0.001), thus stone removal efficiency was higher in eSMP (13.71 ± 1.18 vs. 9.82 ± 1.24 mm³/h, t = 15.499, p < 0.001). Intra-operative RPP in mPCNL was higher than eSMP (17.72 ± 3.33 vs. 12.03 ± 2.37 mmHg, t = 9.524, p < 0.001); accumulated time of backflow status (RPP > 30 mmHg) in mPCNL was longer than eSMP (23.3 ± 16.9 vs. 3.7 ± 4.2 s, t = 7.710, p < 0.001). There was no significant difference in postoperative fever rate between mPCNL and eSMP (12.77% vs. 4.34%, χ² = 2.095, p = 0.148), nor final stone-free rate (87.2% vs. 91.3%, χ² = 0.401, p = 0.526). Hospital stay in eSMP was shorter than mPCNL (2.54 ± 0.72 vs. 3.00 ± 0.88, t = 2.724, p = 0.008).

CONCLUSION

Enhanced SMP (eSMP) was safe and effective in the management of 2-5 cm renal calculus. It can keep a lower renal pelvic pressure and a higher stone removal efficiency when compared to conventional Chinese mini-PCNL.

CLINICAL TRIAL REGISTRATION

NC03206515.

Risk factors for hemorrhage requiring embolization after percutaneous nephrolithotomy: a meta-analysis

Background

The aim of this meta-analysis was to systematically review and identify the risk factors for severe hemorrhage after percutaneous nephrolithotomy (PCNL).

Methods

We searched the PubMed and EMBASE database for literature related to the risk factors of severe hemorrhage after PCNL requiring angiography and embolization through to September 2019. The necessary data for each eligible study were extracted by 2 independent reviewers. The Newcastle-Ottawa Scale (NOS) was used for assessing the methodological quality of the included studies. Statistical analyses were conducted using Comprehensive Meta-Analysis version 2 to identify whether there was a statistical association between risk factors and severe hemorrhage post-PCNL.

Results

The results of this meta-analysis showed that urinary tract infection (UTI) (OR =1.98, 95% CI, 1.21–3.26, P=0.007), diabetes mellitus (OR =4.07, 95% CI, 1.83–9.06, P=0.001), staghorn stone (OR =3.49, 95% CI, 1.25–9.76, P=0.017), and multiple tracts (OR =2.09, 95% CI, 1.33–3.28, P=0.001) were independent risk factors for severe hemorrhage post-PCNL, while hypertension (OR =1.18, 95% CI, 0.58–2.42, P=0.65) showed no significant statistical difference.

Conclusions

Urologists should focus on the above identified risk factors for severe hemorrhage post-PCNL, including UTI, diabetes mellitus, staghorn stone, and multiple tracts. More high-quality studies with larger sample sizes are needed to validate these conclusions.

The impact of post PCNL tube type on blood loss and postoperative pain

Objective:

To evaluate the impact of nephrostomy tube type on postoperative pain and blood loss following percutaneous nephrolithotomy (PCNL).

Methods:

This is a prospective non-randomized study performed at Aga Khan University Hospital from July 2017 to June 2018. In this study we prospectively studied adult patients (16 to 65 years) who underwent unilateral PCNL. Patients who had nephrostomy with balloon (12Fr Foley’s catheter) were compared with patients who had nephrostomy without balloon (12Fr Nelaton™ catheter). STONE Nephrolithometry score was used to assess the stone complexity. Mean pain score at six and 24 hours and mean hemoglobin drop at 24 hours was compared between two groups using independent sample t-test, p-value of <0.05 was considered significant.

Results:

Over one year, 198 PCNL were performed out of which 119 were included for analysis. Sixty-six had nephrostomy tube with balloon and 53 had nephrostomy tube without balloon. Mean STONE score (9.66±1.4 vs. 9.64±1.24) and operative time (72.84±28.34 vs. 86.05±32.1 minutes) was comparable. Mean postoperative pain score at 6 hours and 24 hours postoperative was significantly lower in balloon group as compared to without balloon group. Mean Hemoglobin drop was similar in both groups (p=0.60).

Conclusion:

The use of nephrostomy tube with balloon after PCNL as this is associated with less pain and comparable hemoglobin drop as compare to nephrostomy tube without balloon.

Simultaneous Ureteral and Renal Foreign Bodies

Clinical presentation of patients with foreign bodies is highly variable. We received a 55-year-old female patient with fever and right flank pain. She was treated previously for kidney stones by percutaneous nephrolithtomy with partial resolution, requiring renal embolization during this procedure because of bleeding. CT evidenced metallic density images localized in kidney and ureter, associated with kidney stones located in lower calix. Semirigid ureteroscopy and retrograde intrarenal surgery were performed, revealing the presence of foreign bodies in both localizations and lower calix stones. Complete removal of foreign bodies and stones was performed. Foreign bodies were found to be embolization coils applied in the previous procedure.

The Analysis of Risk Factors for Hemorrhage Associated with Minimally Invasive Percutaneous Nephrolithotomy

Objective

This study investigated the risk factors for bleeding during minimally invasive percutaneous nephrolithotomy, so as to prevent the occurrence of bleeding and improve the surgical effect.

Patients and Methods

The data of 396 patients who underwent percutaneous nephrolithotomy by an experienced surgeon between May 2014 and December 2017 were retrospectively analyzed. To identify the risk factors for bleeding during percutaneous nephrolithotomy, each group was stratified according to the decrease in median hemoglobin. Age, gender, body mass index, stone size, operation time, stone type, degree of hydronephrosis, number of accesses, puncture guidance, underlying disease (diabetes; hypertension), and previous surgical history were evaluated. Univariate analysis was performed to calculate the potential factors. In order to determine the independence of each factor, we finally selected stone size, staghorn stone, degree of hydronephrosis, and operation time. Multivariate logistic regression analysis was used to identify the risk factors for bleeding during minimally invasive percutaneous nephrolithotomy.

Results

A total of 396 patients were successfully treated with percutaneous nephrolithotomy. The univariate analysis demonstrated that the potential risk factors for bleeding during percutaneous nephrolithotomy included stone size, type of stone, operative time, and degree of hydronephrosis. According to the previous studies, stone size, staghorn stone, degree of hydronephrosis, and operation time were ultimately selected. Multivariate logistic regression analysis was used to identify the risk factors for bleeding during percutaneous nephrolithotomy. According to the outcome of logistic regression analysis, stone size, staghorn stone, operation time, and degree of hydronephrosis were the risk factors for bleeding during minimally invasive percutaneous nephrolithotomy.

Conclusions

Percutaneous nephrolithotomy is an effective method for the treatment of upper urinary calculi with few complications. According to the results achieved by an experienced surgeon, the size of stone, staghorn stone, operation time, and degree of hydronephrosis were associated with the bleeding during minimally invasive percutaneous nephrolithotomy.

Predictors for severe hemorrhage requiring angioembolization post percutaneous nephrolithotomy: A single-center experience over 3 years

Context and Aim

About 1% of the patients undergoing percutaneous nephrolithotomy (PCNL) have bleeding severe enough to require angioembolization. We identified factors which could predict severe bleeding post-PCNL and reviewed patients who underwent angioembolization for the same.

Settings and Design

This is a single-institutional, retrospective study over a period of 3 years.

Subjects and Methods

We retrospectively studied 583 patients undergoing PCNL at our institute from 2013 to 2016. We analyzed nine patients (three from our institute and six referred patients) who underwent angioembolization for severe bleeding post-PCNL. We analyzed the preoperative characteristics, intraoperative findings, and postoperative course of these patients and compared this with those patients who did not have a severe post-PCNL bleeding.

Statistical Analysis Used

Fischer's exact test and Chi-square test were used in univariate analysis. Logistic regression analysis was used in multivariate analysis with a value of P < 0.05 considered statistically significant.

Results

Three of the 583 patients (0.51%) who underwent PCNL at our institute required embolization to control bleeding. Preoperative characteristics that were significant risk factors for severe bleeding were a history of ipsilateral renal surgery (P = 0.0025) and increased stone complexity (P = 0.006), while significant intraoperative factors were injury to the pelvicalyceal system (P = 0.0005) and multiple access tracts (P = 0.022). Angiography revealed arteriovenous fistula in two patients and a pseudoaneurysm in seven patients. All patients underwent successful superselective angioembolization with preserved renal perfusion in six patients on control angiography postembolization.

Conclusions

History of ipsilateral renal surgery, increased stone complexity, multiple access tracts, and injury to the pelvicalyceal system are risk factors predicting severe renal hemorrhage post-PCNL. Early angiography followed by angioembolization should be performed in patients with severe post-PCNL bleeding who fail to respond to conservative measures.

Subcostal artery bleeding after percutaneous nephrolithotomy: a case report and literature review

Postoperative bleeding is a dangerous complication after percutaneous nephrolithotomy (PCNL). Pseudoaneurysm, arteriovenous fistula, and arterial laceration are the three most common causes of post-PCNL bleeding. Subcostal artery bleeding is a rare cause. We herein present a clinical case involving a 43-year-old man who presented with right renal complex calculi and was managed by PCNL in the prone position using an inferior calyceal puncture approach. Intermittent extreme bleeding occurred 1 day postoperatively, and immediate renal angiography was performed. However, we found no sign of a pseudoaneurysm, arteriovenous fistula, or arterial laceration. Another well-trained and experienced doctor also found no pseudoaneurysm, arteriovenous fistula, or arterial laceration. After adjusting the catheter position, subcostal artery bleeding finally appeared and was successfully controlled by coils. This finding indicates that subcostal artery damage is one cause of post-PCNL bleeding. We suggest that clinicians should carefully and patiently perform angiography and/or embolization to avoid misdiagnosis and mistreatment.

Blood loss predictive factors and transfusion practice during percutaneous nephrolithotomy of kidney stones: a prospective study

Objectives

Bleeding is the most common complication of percutaneous nephrolithotomy (PCNL). Injudicious transfusion is frequently performed in current practice, even though it is not always needed. This study aimed to identify the predictive factors of blood loss in the PCNL procedure and evaluate the perioperative transfusion practice.

Methods

A prospective study of PCNL was randomly performed by two consultants of endo-urology at our institution. The inclusion criteria were adults with kidney pelvic stones >20 mm or stone in inferior calyx >10 mm or staghorn stone. Those with coagulopathy, under anti-coagulant treatment or open conversion were excluded. A full blood count was taken at baseline and during 12, 24, 36, 72-hours post-operatively. Factors such as stone burden, sex, body surface area, shifting of hematocrit level and amount of blood transfused were analyzed statistically using line regression to identify the predictive factors of total blood loss (TBL).

 

Results

Eighty-five patients were enrolled in this study. Mean TBL was 560.92 ± 428.43 mL for both endo-urology surgeons. Stone burden was the most influential factor for TBL (p=0.037). Our results revealed that TBL (mL) = -153.379 + 0.229 × stone burden (mm2) + 0.203 x baseline serum hematocrit (%); thus considerably predicted the need for blood transfusion. A total of 87.1% patients did not receive perioperative transfusion, 3.5% received intra-operative transfusion, 7.1% received post-operative transfusion, 23% had both intra and post-operative transfusion, resulting in a cross-matched transfusion ratio of 7.72. Mean perioperative blood transfused was 356.00 ± 145.88 mL.