Renal Artery Embolization Research Articles

SUPERSELECTIVE EMBOLIZATION OF THE RENAL ARTERIES AS A MONOTHERAPY OF KIDNEY TUMOR IN A PATIENT WITH HIGH ANESTHESIOLOGIC RISK

Introduction: Renal artery embolization is a minimally invasive X-ray endovascular operation that is used in the treatment of various urological diseases. This operation is of increasing interest due to its ability to occlude not only proximal, but also distal renal vessels with a low risk of complications. Recent developments in endovascular technology make embolization one of the effective and safe methods applicable to stop renal bleeding, preoperative preparation for surgical treatment of renal malignant tumors, and first-line treatment for angiomyolipomas. For a certain category of patients, renal artery embolization is practically no alternative method of treatment. This applies to comorbid patients with kidney tumors and aggravated somatic status, in whom the anesthetic risk makes open or laparoscopic surgical treatment impossible, and embolization can reduce symptoms, improve the quality of life of such patients and prolong the patient's life.Clinical case: we demonstrate the experience of X-ray surgical treatment of cT1aN0M0 left kidney cancer in an 80-year-old patient.Conclusion: Embolization of renal arteries in some cases can be an effective and safe alternative treatment for renal cell carcinoma in somatically burdened patients who cannot perform surgical treatment.

A preliminary animal study of thermal rheology fluid as a new temperature-dependent liquid intravascular embolic material

PurposeThermal rheology (TR) fluid, which comprises polyethylene (PE) particles, their dispersant, and solvent, is a material that increases in viscosity to various degrees depending on the type and ratio of these constituents when its temperature rises. The viscosity of type 1 (TRF-1) increases more than that of type 2 (TRF-2) near rabbit body temperature. This preliminary animal study aimed to determine the basic characteristics and embolic effect of TR fluid by comparing TRF-1 and TRF-2.Materials and methodsTwenty-four Japanese white rabbits underwent unilateral renal artery embolization using TRF-1 or TRF-2 and follow-up angiography at 7 or 28 days (4 subgroups, n = 6 each). Subsequently, the rabbits were euthanized, and the embolized kidneys were removed for pathological examination. The primary and final embolization rates were defined as the ratio of renal artery area not visible immediately after embolization and follow-up angiography, respectively, to visualized renal artery area before embolization. The final embolization rate and maximum vessel diameter filled with PE particles were compared between materials. Moreover, the embolic effect was determined to be persistent when a two-sided 95% confidence interval (CI) for the difference in means between the embolization rates was < 5%.ResultsThe final embolization rate was significantly higher for the TRF-1 than for the TRF-2 at both 7 (mean 80.7% [SD 18.7] vs. 28.4% [19.9], p = 0.001) and 28 days (94.0% [3.5] vs. 37.8% [15.5], p < 0.001). The maximum occluded vessel diameter was significantly larger for TRF-1 than for TRF-2 (870 µm [417] vs. 270 µm [163], p < 0.001). The embolic effect of TRF-1 was persistent until 28 days (difference between rates − 3.3 [95% CI − 10.0–3.4]).ConclusionThe embolic effect of TRF-1 was more persistent than that of TRF-2, and the persistency depended on the type and ratio of TR fluid constituents.

Multicentre Outcomes of Redo Fenestrated/Branched Endovascular Aneurysm Repair to Rescue Failed Fenestrated Endografts

To report the outcomes of redo fenestrated and/or branched endovascular aortic repair (F/BEVAR in FEVAR) to rescue previous failed FEVAR. Retrospective review of all consecutive patients undergoing F/BEVAR in FEVAR at eight aortic centres including pre-, intra-, and post-operative data according to a pre-established protocol. Follow up consisted of at least yearly computed tomography angiography. Values are presented as median and interquartile range, and survival as estimate ± standard error in percentage. 18 male patients (76 years old; range 69 – 78 years) receiving FEVAR involving two (two or three) target vessels between 2006 and 2016 underwent F/BEVAR in FEVAR between 2012 and 2019 (aneurysm diameter of 63 mm; range 56 – 69 mm). Median interval between the procedures was 53 (29 – 103) months. The indication for F/BEVAR in FEVAR was type Ia endoleak in 16 cases (eight isolated and eight combined with graft migration), one graft migration without endoleak and one migration with significant proximal aortic expansion. F/BEVAR in FEVAR involved all patent renovisceral arteries and had an operating time of 260 (204 – 344) minutes. Technical success was achieved in 15 (83%) cases. There was a failure to bridge one renal artery, one renal capsular bleed with the subsequent need for renal artery embolisation within 24 hours and one persistent type Ib endoleak despite iliac extension. There was no peri- or in hospital death. Two patients developed spinal cord ischaemia, one transient paraparesis and one permanent paraplegia. The latter occurred in a non-staged procedure where spinal drainage was used. During a follow up of 27 (7 – 39) months, three (17%) patients underwent late re-interventions. Overall survival at 24 months was 70 ± 11% with no aneurysm related death and a secondary clinical success at 24 months of 84 ± 11%. F/BEVAR in FEVAR is a technically challenging but feasible solution to rescue failed FEVAR. The outcomes are promising in many aortic centres but need to be confirmed by further studies with longer follow up.

First experience of superselective embolization of renal arteries supplying the tumor with subsequent laparoscopic kidney resection

Background. Patients with signs of tumor lesions in a single kidney or in the only one functioning kidney, with bilateral renal tumors are at high risk of functional failure or insufficiency of the kidney after surgery. Joint discussions with specialists in X-ray endovascular surgeries resulted in the development of a treatment algorithm for patients with localized kidney cancer who require organ-sparing surgery without ischemic kidney resection.Objective: to evaluation of the immediate results of two-stage surgical treatment of localized kidney cancer in patients with signs of tumor lesions in a single kidney or in the only one functioning kidney, with bilateral renal tumors, including superselective embolization of the artery supplying the tumor at the first stage, and laparoscopic kidney resection without renal ischemia parenchyma at the second stage.Materials and methods. This study included 5 patients with localized kidney cancer, who underwent two-stage treatment at Moscow Regional Oncology Dispensary between 24.03.2021 and 19.04.2021. The first stage included superselective embolization of the artery supplying the tumor; the second stage implied laparoscopic kidney resection 6-7 days following the first stage.Results. The median age of the patients was 62 years (range: 42-73 years). Four patients (80%) had unilateral kidney lesions, while 1 patient (20 %) had bilateral (synchronous) kidney cancer. The mean RENAL score was 8 (range: 6-10); patients were distributed as follows: score 4-6 in 40 %, score 7-9 in 40 %, and score &gt;10 in 20 % of patients. At the first stage, patients underwent endovascular embolization of the branches of the renal artery. Patients had superselective embolization of either middle (n = 3; 60 %), upper (n = 1; 20 %), or lower (n = 1; 20 %) segmental arteries supplying the tumor. In one of them (20 %), we identified 3 large arterial branches; in another one (20 %), we identified 2 large arterial branches.At the second stage, we performed laparoscopic kidney resection. None of the patients required renal artery clamping, because there was an excellent visualization of the demarcation zone and no significant blood loss. The resection area was sutured in 1 case (20 %). In 2 individuals (40 %), a hemostatic sponge was installed in the removed tumor bed. In the remaining 2 cases (40 %), hemostasis was ensured by coagulation. The median blood loss was 100 mL (range: 50-200 mL). The postoperative period was uneventful in all patients. None of the patients developed symptoms of acute renal failure.Conclusion. Thus, superselective embolization of arteries supplying a kidney tumor has undeniable advantages in organ-sparing surgeries for patients with localized kidney cancer and some additional kidney problems, when organ preservation is crucial for patient's life.

Utility of preoperative vascular embolization of renal tumors with left renal vein tumor thrombus

Introduction and objectivesPreoperative renal artery embolization (PRAE) for large renal masses may be performed prior to nephrectomy in order to simplify the procedure and reduce intraoperative bleeding. The objective of this work is to determine the role of PRAE on intraoperative bleeding and postoperative complications in left renal tumors with tumor thrombus limited to the left renal vein (level 0). Material and methodsRetrospective analysis to evaluate 46 patients who underwent left radical nephrectomy and thrombectomy for the treatment of renal cell carcinoma with level 0 tumor thrombus during the period 1990–2020. PRAE was limited to those cases in which surgical access to the main renal artery was presumed a priori difficult in the preoperative imaging study (n = 9; 19.6%). Intraoperative bleeding was estimated based on the perioperative transfusion rate, and postoperative complications were categorized according to the Clavien–Dindo classification. The Chi-squared test was used for comparisons. A multivariate analysis was performed to identify predictors of transfusion and complications. ResultsThere were no significant differences in the overall complication rate (11.1% vs. 32.4%, p = 0.19), major complication rate (0% vs. 8.1%, p = 0.51), or transfusion rate (11.1% vs. 19%, p = 0.49) between both groups (PRAE vs. non-PRAE). In the multivariate analysis, PRAE did not behave as a predictor of complications (OR: 0.11, 95%CI 0.01–2.86; p = 0.18) nor transfusion (OR: 0.46, 95%CI 0.02–7.38; p = 0.58). ConclusionsIn our study on left RCC with level 0 tumor thrombus and difficult access to the main renal artery, PRAE was not associated with increased bleeding or postoperative complications, and it did not behave as an independent predictor of these variables. Therefore, it could be used as a preoperative maneuver to facilitate vascular management in selected cases.

P088 - Renal tumors with left renal vein tumoral thrombosis. Is Preoperative Renal Artery Embolization (PRAE) helpful?

P088 - Renal tumors with left renal vein tumoral thrombosis. Is Preoperative Renal Artery Embolization (PRAE) helpful?

Necessity of repeated renal arteriography in the treatment of severe hemorrhage after percutaneous nephrolithotomy

In order to discuss the necessity of repeated renal arteriography in the treatment of severe bleeding after percutaneous nephrolithotomy, this study retrospectively analyzed the clinical data of patients with severe bleeding after percutaneous nephrolithotomy in the Department of Urology Surgery of the First Hospital of China Medical University from August 2010 to July 2020, summarily analyzing treatments, outcomes and follow-up results of 27 patients who were treated by renal arteriography more than twice. Of these 27 patients who underwent repeated renal arteriography, 23 of them were treated by two times, 4 by three times, all of whom were diagnosed as renal vascular injury. And 15 of them were diagnosed as pseudoaneurysm, 4 of them renal arteriovenous fistula, and 8 of them pseudoaneurysm combined with renal arteriovenous fistula. After clear diagnosis, all these patients were performed with renal artery embolization, after which the symptoms of hematuria and lumbar discomfort were relieved or disappeared immediately. These patients were followed up from 6 months to 5 years, without corresponding symptoms recurring and with the renal function equivalent to that before embolization. The results showed that repeated renal arteriography was of great significance in the treatment of patients with severe bleeding after percutaneous nephrolithotomy, helping to clarify the cause of bleeding and giving appropriate and timely treatment.

Prevalence and risk factors of myocardial and acute kidney injury following radical nephrectomy with vena cava thrombectomy: a retrospective cohort study

BackgroundRadical nephrectomy with thrombectomy is the mainstay treatment for patients with renal cell carcinoma with vena cava thrombus. But the procedure is full of challenge, with high incidence of major complications and mortality. Herein, we investigated the incidence and predictors of myocardial injury and acute kidney injury (AKI) in patients following radical nephrectomy with inferior vena cava thrombectomy.MethodsPatients who underwent nephrectomy with thrombectomy between January 2012 and June 2020 were retrospectively reviewed. Myocardial injury was diagnosed when peak cardiac troponin I was higher than 0.03 ng/ml. AKI was diagnosed according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Multivariable logistic regression models were used to identify predictors of myocardial injury or AKI after surgery.ResultsA total of 143 patients were included in the final analysis. Myocardial injury and AKI occurred in 37.8 and 42.7% of patients after this surgery, respectively. Male sex (odds ratio [OR] 0.27, 95% confidence interval [CI] 0.10–0.71; P = 0.008) was associated with a lower risk, whereas high level Mayo classification (compared with Mayo level I + II, Mayo level III + IV: OR 4.21, 95% CI 1.42–12.4; P = 0.009), acute normovolemic hemodilution before surgery (OR 2.66, 95% CI 1.10–6.41; P = 0.029), long duration of intraoperative tachycardia (per 20 min: OR 1.49, 95% CI 1.10–2.16; P = 0.036), and long duration of surgery (per 1 h, OR 1.48, 95% CI 1.03–2.16, P = 0.009) were associated with a higher risk of myocardial injury. High body mass index (OR 1.18, 95% CI 1.06–1.33; P = 0.004) and long duration of intraoperative hypotension (per 20 min: OR 1.30, 95% CI 1.04–1.64; P = 0.024) were associated with a higher risk, whereas selective renal artery embolism before surgery (OR 0.20, 95% CI 0.07–0.59, P = 0.004) was associated with a lower risk of AKI.ConclusionMyocardial injury and AKI were common in patients recovering from radical nephrectomy with inferior vena cava thrombectomy. Whether interventions targeting the above modifiable factors can improve outcomes require further studies.

284 Wunderlich Syndrome - Case Report of a Surgical Emergency Due to Spontaneous Non-Traumatic Retroperitoneal Haemorrhage

Abstract A 42-year-old female with no other significant co-morbidities presented with complaints of sudden onset abdominal pain, she was in state of shock- her haemoglobin dropped drastically to 6.8g/dl from 11.8g/dl. She was resuscitated and was given blood transfusion. CT Scan was suggestive of retroperitoneal haemorrhage due to rupture of Renal angiomyolipoma (RAML). Patient underwent selective embolization of renal artery the next day and was discharged after 3 days of post-operative stay. Wunderlich Syndrome-is a rare condition in which spontaneous nontraumatic renal haemorrhage occurs into the subcapsular and perirenal spaces is most commonly caused due to spontaneous rupture of RAML.It is characterized by Lenk’s triad – Acute flank pain, flank mass, hypovolemic shock. Size of AML (&amp;gt;4 cm), prothrombotic states such as pregnancy are main causes of AML rupture. Patients are managed conservatively or with help of selective arterial embolization. Nephrectomy is last resort in a hemodynamically unstable patient or in cases of embolization failure. When dealing with acute abdomen with haemodynamic instability in non-traumatic cases it is essential to consider possibility of Wunderlich Syndrome. Early diagnosis, availability of Interventional radiology is key to successful management and potentially avoiding a Nephrectomy.

SC259 - Potential benefit of renal artery embolization on oncological outcomes in a contemporary cohort of patients with locally advanced renal cell carcinoma

SC259 - Potential benefit of renal artery embolization on oncological outcomes in a contemporary cohort of patients with locally advanced renal cell carcinoma

Non-Permanent Transcatheter Proximal Renal Artery Embolization for a Grade 5 Renal Injury with Delayed Recanalization and Preserved Renal Parenchymal Enhancement

&lt;p&gt;Super-selective renal artery embolization is an increasingly popular technique for the management of traumatic, low-grade renal trauma. When performed in distal arterial branches, this intervention enables tissue preservation and arrest of hemorrhage, but it may not be practical in cases of multifocal, high-grade renal injuries. In such cases, surgical nephrectomy remains the more common treatment modality to ensure hemodynamic control. We present the unique case of a patient who presented in hemorrhagic shock following a major trauma that resulted in a grade 5 renal injury treated with complete renal artery embolization using Gelfoam, resulting in hemodynamic stabilization. Interestingly, imaging 1 month after embolization revealed residual enhancement of the inferior pole of the kidney, suggesting reconstitution of flow and partial renal salvage. Ultimately, transcatheter “nephrectomy” with careful selection of a temporary embolic agent may serve as a safe and efficient alternative to surgical nephrectomy with the added possibility of preserving partial renal perfusion and function in the emergent setting.&lt;/p&gt;

A case report of post-surgical page kidney due to extensive renal hematoma following percutaneous nephrolithotomy

Introduction and importancePost-surgical Page kidney due to large renal hematoma following percutaneous nephrolithotomy (PCNL) is a rare significant complication that may lead to loss of a kidney.Case presentationA 50-year-old lady underwent elective left side PCNL for a 3 cm renal pelvis stone, and one week later, she presented back with a massive renal hematoma with high blood pressure.Clinical discussionThe ultrasound abdomen and computed tomography diagnosed a page kidney due to massive intrarenal and perirenal hematoma as a complication of PCNL. Angioembolization and percutaneous aspiration were failed, and the antihypertensives also failed to control the blood pressure. Therefore, she underwent a left-side simple nephrectomy and had an uneventful recovery with reversal of normal blood pressure.ConclusionPost-surgical page kidney needs to identify early to facilitate the percutaneous radiological interventions that may preserve the renal parenchyma and avoid further surgeries. Nevertheless, late cases or the failed radiologically intervened cases need open renal exploration and simple nephrectomy, which may be the bailed-out procedure to reverse the consequence of page kidney.

Reduced nitric oxide bioavailability impairs myocardial oxygen balance during exercise in swine with multiple risk factors

In the present study, we tested the hypothesis that multiple risk factors, including diabetes mellitus (DM), dyslipidaemia and chronic kidney disease (CKD) result in a loss of nitric oxide (NO) signalling, thereby contributing to coronary microvascular dysfunction. Risk factors were induced in 12 female swine by intravenous streptozotocin injections (DM), a high fat diet (HFD) and renal artery embolization (CKD). Female healthy swine (n = 13) on normal diet served as controls (Normal). After 5 months, swine were chronically instrumented and studied at rest and during exercise. DM + HFD + CKD swine demonstrated significant hyperglycaemia, dyslipidaemia and impaired kidney function compared to Normal swine. These risk factors were accompanied by coronary microvascular endothelial dysfunction both in vivo and in isolated small arteries, due to a reduced NO bioavailability, associated with perturbations in myocardial oxygen balance at rest and during exercise. NO synthase inhibition caused coronary microvascular constriction in exercising Normal swine, but had no effect in DM + HFD + CKD animals, while inhibition of phosphodiesterase 5 produced similar vasodilator responses in both groups, indicating that loss of NO bioavailability was principally responsible for the observed coronary microvascular dysfunction. This was associated with an increase in myocardial 8-isoprostane levels and a decrease in antioxidant capacity, while antioxidants restored the vasodilation to bradykinin in isolated coronary small arteries, suggesting that oxidative stress was principally responsible for the reduced NO bioavailability. In conclusion, five months of combined exposure to DM + HFD + CKD produces coronary endothelial dysfunction due to impaired NO bioavailability, resulting in impaired myocardial perfusion at rest and during exercise.

Comparison of transradial and transfemoral access for transcatheter arterial embolization of iatrogenic renal hemorrhage.

BackgroundThere are few reports of renal artery embolization (RAE) via transradial access (TRA) for renal hemorrhage, and none have compared outcomes of RAE via TRA and transfemoral access (TFA). The objective was to compare technical and clinical outcomes in patients undergoing RAE via TRA or TFA for iatrogenic renal hemorrhage.Materials and methodsThis study included 45 RAE procedures (16 TRA and 29 TFA) for iatrogenic renal hemorrhage in 43 patients performed at a tertiary referral center between October 2018 and December 2020. Information regarding underlying diseases, coagulation status, angiographic and embolization procedure details, technical and clinical successes, and complications were retrospectively evaluated.ResultsThere were no differences in demographics, underlying diseases, updated Charlson comorbidity scores, angiographic findings, and volume of contrast material between the TRA and TFA groups. By contrast, prothrombin time and international normalized ratio were significantly lower in the TRA than in the TFA group. Embolic materials differed significantly in the two groups. Procedure duration, fluoroscopy time, digital subtraction angiography number, and dose area product were slightly lower in the TRA than in the TFA group, but the differences were not statistically significant. Technical and clinical success rates in the TRA and TFA groups were 100% and 96.6%, and 100% and 96.6%, respectively. No patient in either group experienced procedure-related complications during a 4 week follow-up period.ConclusionRAE via TRA in the management of iatrogenic renal hemorrhage was safe and feasible, with similar procedure duration and radiation exposure to RAE via TFA. TRA may be an acceptable alternative to TFA in these patients.

Editor's Choice – Multicentre Outcomes of Redo Fenestrated/Branched Endovascular Aneurysm Repair to Rescue Failed Fenestrated Endografts

To report the outcomes of redo fenestrated and/or branched endovascular aortic repair (F/BEVAR in FEVAR) to rescue previous failed FEVAR. Retrospective review of all consecutive patients undergoing F/BEVAR in FEVAR at eight aortic centres including pre-, intra-, and post-operative data according to a pre-established protocol. Follow up consisted of at least yearly computed tomography angiography. Values are presented as median and interquartile range, and survival as estimate ± standard error in percentage. 18 male patients (76 years old; range 69 - 78 years) receiving FEVAR involving two (two or three) target vessels between 2006 and 2016 underwent F/BEVAR in FEVAR between 2012 and 2019 (aneurysm diameter of 63 mm; range 56 - 69 mm). Median interval between the procedures was 53 (29 - 103) months. The indication for F/BEVAR in FEVAR was type Ia endoleak in 16 cases (eight isolated and eight combined with graft migration), one graft migration without endoleak and one migration with significant proximal aortic expansion. F/BEVAR in FEVAR involved all patent renovisceral arteries and had an operating time of 260 (204 - 344) minutes. Technical success was achieved in 15 (83%) cases. There was a failure to bridge one renal artery, one renal capsular bleed with the subsequent need for renal artery embolisation within 24 hours and one persistent type Ib endoleak despite iliac extension. There was no peri- or in hospital death. Two patients developed spinal cord ischaemia, one transient paraparesis and one permanent paraplegia. The latter occurred in a non-staged procedure where spinal drainage was used. During a follow up of 27 (7 - 39) months, three (17%) patients underwent late re-interventions. Overall survival at 24 months was 70 ± 11% with no aneurysm related death and a secondary clinical success at 24 months of 84 ± 11%. F/BEVAR in FEVAR is a technically challenging but feasible solution to rescue failed FEVAR. The outcomes are promising in many aortic centres but need to be confirmed by further studies with longer follow up.

Haemochromatosis in a kidney transplant recipient: a case report

BackgroundIron overload is inevitably related to chronic kidney disease (CKD) treatment. Haemochromatosis leads to multiorgan damage and is associated with increased mortality. Primary haemochromatosis is the most common autosomal recessive disease in white populations. In most cases, the classic form of hereditary haemochromatosis is caused by mutations, mainly C282Y and H63D, in the haemochromatosis gene (HFE). Secondary haemochromatosis can be triggered by iron administration and blood transfusions. Haemochromatosis is rarely reported in kidney transplant recipients. Atypical factors may evoke haemochromatosis in patients without HFE mutations or other standard risk factors.Case presentationIn the current study, we present a patient who started to have haemochromatosis symptoms after kidney transplantation. A 37-year-old man after kidney transplantation from a deceased donor was admitted to the hospital due to high serum ferritin levels and impaired graft function. The patient’s past medical history included arterial hypertension, embolization of both renal arteries and necrosis of the left femoral head. Glomerulonephritis was suspected as a cause of CKD; however, severe kidney failure was diagnosed, kidney biopsy was not performed, and the patient started intermittent haemodialysis. While on dialysis to treat anaemia, the patient had received erythropoietin and iron intravenously, and the maximal serum ferritin level was 2115 ng/ml. After kidney transplantation, ferritin levels started to increase rapidly, with a maximum level of 9468 ng/ml one and a half years after surgery. His genetic study showed HFE C282Y heterozygosity. Symptoms of haemochromatosis, such as skin hyperpigmentation, elevated activity of aminotransferases, impaired glucose tolerance and heart failure, were observed. Therapeutic phlebotomy was started, and 36 procedures were performed. After treatment, graft function significantly improved, most haemochromatosis symptoms resolved, and the serum ferritin level significantly decreased.ConclusionsHaemochromatosis can occur in heterozygotic HFE patients after kidney transplantation. Iron administration, infections, type of immunosuppression and liver dysfunction should be considered potential triggers of haemochromatosis in this group of patients.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding

Background/AimsThe most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy. MethodsIn this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed. ResultsBefore propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120). ConclusionsWe do not recommend desmopressin administration before kidney biopsy.

Utilidad de la embolización vascular prequirúrgica de tumores renales con trombo tumoral en la vena renal izquierda

Introduction and objectivesPreoperative renal artery embolization (PRAE) for large renal masses may be performed prior to nephrectomy in order to simplify the procedure and reduce intraoperative bleeding. The objective of this work is to determine the role of PRAE on intraoperative bleeding and postoperative complications in left renal tumors with tumor thrombus limited to the left renal vein (level 0). Material and methodsRetrospective analysis to evaluate 46 patients who underwent left radical nephrectomy and thrombectomy for the treatment of renal cell carcinoma with level 0 tumor thrombus during the period 1990-2020. PRAE was limited to those cases in which surgical access to the main renal artery was presumed a priori difficult in the preoperative imaging study (n=9; 19.6%). Intraoperative bleeding was estimated based on the perioperative transfusion rate, and postoperative complications were categorized according to the Clavien-Dindo classification. The Chi-squared test was used for comparisons. A multivariate analysis was performed to identify predictors of transfusion and complications. ResultsThere were no significant differences in the overall complication rate (11.1% vs. 32.4%, P=.19), major complication rate (0% vs.8.1%, P=.51), or transfusion rate (11.1% vs. 19%, P=.49) between both groups (PRAE vs. non-PRAE). In the multivariate analysis, PRAE did not behave as a predictor of complications (OR:0.11, 95%CI 0.01-2.86; P=.18) nor transfusion (OR:0.46, 95%CI 0.02-7.38;P=.58). ConclusionsIn our study on left renal cell carcinomas with level 0 tumor thrombus and difficult access to the main renal artery, PRAE was not associated with increased bleeding or postoperative complications, and it did not behave as an independent predictor of these variables. Therefore, it could be used as a preoperative maneuver to facilitate vascular management in selected cases.

Safety of Renal Biopsy by Physicians with Short Nephrology Experience.

Percutaneous renal biopsy is an essential tool for diagnosing various renal diseases; however, little is known about whether renal biopsy performed by physicians with short nephrology experience is safe in Japan. This study included 238 patients who underwent percutaneous renal biopsy between April 2017 and September 2020. We retrospectively analyzed the frequency of post-renal biopsy complications (hemoglobin decrease of ≥10%, hypotension, blood transfusion, renal artery embolization, nephrectomy and death) and compared their incidence among physicians with varied experience in nephrology. After renal biopsy, a hemoglobin decrease of ≥10%, hypotension and transfusion occurred in 13.1%, 3.8% and 0.8% of patients, respectively. There were no cases of post-biopsy renal artery embolism, nephrectomy, or death. The composite complication rate was 16.0%. The incidence of post-biopsy complications was similar between physicians with ≥3 years and <3 years of clinical nephrology experience (12.5% vs. 16.8%, p = 0.64). Furthermore, the post-biopsy composite complication rates were similar between physicians with ≥6 months and <6 months of clinical nephrology experience (16.3% vs. 15.6%, p > 0.99). Under attending nephrologist supervision, a physician with short clinical nephrology experience can safely perform renal biopsy.

A Uremic Goat Model Created by Subtotal Renal Artery Embolization and Gentamicin.

Simple SummaryTo improve the treatment of patients with kidney disease, new renal replacement therapies are being developed. Prior to their use in humans with end-stage kidney disease (ESKD), these therapies need to be tested in animals with kidney disease. Goats seem particularly suitable because they are docile, have bodyweights comparable to humans and easily accessible neck veins to obtain blood access and tolerate frequent blood sampling, allowing for repeated monitoring. To obtain high blood concentrations of waste solutes that accumulate in patients with kidney disease and allow for the evaluation of solute removal by the new renal replacement therapies, we established kidney failure in five goats by partially blocking the blood supply of the kidneys via radiographic embolization. This resulted in stable moderate kidney disease. The administration of high-dose gentamicin caused a temporary further decline in kidney function. Although the response varied with animal, blood concentrations of waste solutes were representative of those found in ESKD patients. These animals can survive for more than ten months in good condition, allowing for the repetitive testing of new therapies in one animal, and therefore limiting the use of laboratory animals.A large animal model of (end-stage) kidney disease (ESKD) is needed for the preclinical testing of novel renal replacement therapies. This study aimed to create stable uremia via subtotal renal artery embolization in goats and induce a temporary further decline in kidney function by administration of gentamicin. Renal artery embolization was performed in five Dutch white goats by infusing polyvinyl alcohol particles in branches of the renal artery, aiming for the embolization of ~80% of one kidney and complete embolization of the contralateral kidney. Gentamicin was administered to temporarily further increase the plasma concentrations of uremic toxins. After initial acute kidney injury, urea and creatinine plasma concentrations stabilized 1.5 ± 0.7 months post-embolization and remained elevated (12 ± 1.4 vs. 5.6 ± 0.8 mmol/L and 174 ± 45 vs. 65 ± 5.6 µmol/L, resp.) during follow-up (16 ± 6 months). Gentamicin induced temporary acute-on-chronic kidney injury with a variable increase in plasma concentrations of small solutes (urea 29 ± 15 mmol/L, creatinine 841 ± 584 µmol/L, phosphate 2.2 ± 0.3 mmol/L and potassium 5.0 ± 0.6 mmol/L) and protein-bound uremic toxins representative of patients with ESKD. A uremic goat model characterized by stable moderate uremia was established via subtotal renal artery embolization with the induction of temporary severe acute-on-chronic kidney injury by the administration of gentamicin, allowing preclinical in vivo validation of novel renal replacement technologies.