Surgical prevention and management of vascular complications of kidney transplantation

Impact of early surgical complications on kidney transplant outcomes

BACKGROUND

Kidney transplantation (KT) improves clinical outcomes of patients with end stage renal disease. Little has been reported on the impact of early post-operative surgical complications (SC) on long-term clinical outcomes following KT. We sought to determine the impact of vascular complications, urological complications, surgical site complications, and peri-graft collections within 30 days of transplantation on patient survival, graft function, and hospital readmissions.

METHODS

We conducted a single-centre, observational cohort study examining adult patients (≥ 18 years) who received a kidney transplant from living and deceased donors between January 1st, 2005 and December 31st, 2015 with follow-up until December 31st, 2016 (n = 1,334). Univariable and multivariable analyses were performed with Cox proportional hazards models to analyze the outcomes of SC in the early post-operative period after KT.

RESULTS

The cumulative probability of SC within 30 days of transplant was 25%, the most common SC being peri-graft collections (66.8%). Multivariable analyses showed significant relationships between Clavien Grade 1 SC and death with graft function (HR 1.78 [95% CI: 1.11, 2.86]), and between Clavien Grades 3 to 4 and hospital readmissions (HR 1.95 [95% CI: 1.37, 2.77]).

CONCLUSIONS

Early SC following KT are common and have a significant influence on long-term patient outcomes.

Evidence-Based Complementary Benefit of the Vascular Surgeon Among the Team of Renal Transplantation; a Single Center Experience

BACKGROUND

In a kidney transplant tertiary referral center; we compared 3 operating team configurations of different surgical specialties to highlight the effect of the operating surgeon's specialty on various operative details and procedural outcome.

METHODS

A total of 50 cases of living donor transplantations were divided into 3 main groups according to the operating surgeons' specialty, the first group (A) includes 12 patients exclusively operated on by urologists with advanced training in transplantation, the second group (B) includes 35 patients operated by combined surgical specialties; a urologist and a vascular surgeon both with advanced transplantation training, and a third group (C) includes 3 cases where the transplant operation commenced with operating urologists as in group (A) but required intraoperative urgent notification of a vascular surgeon to manage unexpected intraoperative technical difficulties or major complications. Cases were studied according to operative details, anastomosis techniques, ischemia times, total procedure time, recovery of urinary output, intensive care unit (ICU) stay, postoperative surgical complications and serum creatinine level for up to 3 years of follow-up.

RESULTS

Study of operative details revealed that total duration of graft ischemia was significantly shorter in group (B) and significantly longer in group (C) (P value 0.001), Total procedural duration also varied significantly between the 3 groups, group (B) being the shortest while group (C) was the longest (P value less than 0.001). Technically; group (A) used only end to end arterial anastomosis as a standard technique, while group (B) used both end-to-end and end-to-side anastomoses as required per each case. End to side anastomosis in group (B) yielded better immediate graft response in the form of change in color, texture, earlier and more profuse postoperative urine volumes (P value 0.025). Furthermore, anastomosis to common and external iliac arteries (group B) yielded earlier and higher urine volumes than the internal iliac artery (P values 0.024 and 0.031 respectively). Group (B) recorded significantly less postoperative perigraft hematomas and lymphoceles compared to the other 2 groups. Equal rates of urine leaks, ICU stay, creatinine levels, patient and grafts survival rates among groups (A) and (B), while postoperative recovery and ICU stay duration were more lengthy in the complicated group (C).

CONCLUSIONS

A vascular surgeon operating in a transplantation team would deal comfortably and efficiently with various vascular related challenges and complications, thus avoiding unnecessary time waste, complications and costs.

Demographic and Clinical Characteristics of Kidney Donors at First Check: A Single-Center Experience

OBJECTIVES

Kidney transplant is the best treatment for patients with end-stage kidney disease. In many regions of the world, including the Middle East, most kidney transplants are from living donors. In contrast to recipients, data for living donors remain scarce. Here, we describe living donor baseline characteristics at first hospital check at a single center in Baghdad, Iraq.

MATERIALS AND METHODS

We collected and analyzed demographic, laboratory, imaging, and histocompatibility data from donor records at the Nephrology and Renal Transplantation Center, Medical City-Baghdad, Baghdad, Iraq, from July 2022 to September 2022.

RESULTS

We included 124 kidney donors (56.4% male) who donated their kidneys 1 to 3 years previous to our study, with a mean age of 34.84 ± 10.04 years and mean body mass index (weight in kilograms divided by height in meters squared) of 27.11 ± 2.12. Most donors donated their kidneys to a firstdegree relative (69.2%); blood group O was the most prevalent (47.5%). More than half of the donors were unemployed. Histocompatibility testing showed that 40% of the donors had >3 human leukocyte antigen mismatches with their recipients, and 30% of the recipients were high-risk sensitized patients with a calculated panel reactive antibody >50%. Regarding the virus status, 68.5% of the donors tested positive for cytomegalovirus immunoglobulin G, 8% of the transplants were high-risk cytomegalovirus status, and 43.5% tested positive for Epstein-Barr virus immunoglobulin G. Renal imaging showed that 75.8% of donors had a single artery and 24.1% had a double artery (26.6% double left, 40% double right, and 33.3% both).

CONCLUSIONS

For living transplant procedures at a single center in Iraq, most were from related donors. Most donors are unemployed, which mandates future health and social support. High immunological and viral risks must not be ignored in a single center with living related donors.

Case report: Application of nonsurgical method in saving transplant renal vein thrombosis caused by acute diarrhea

Transplant renal vein thrombosis is a rare complication after kidney transplantation, which can seriously threaten graft survival. Though the measures like thrombolytic therapy or operative intervention could be taken to deal with this complication, allograft loss is the most common outcome. Thus, early finding as well as decisive intervention is crucial to saving the graft. Here we present a 46-year-old male patient who underwent kidney transplantation from a cadaveric donor who developed a transplant renal venous thrombosis induced by acute diarrhea more than 1 year after renal transplantation with an initial symptom of sudden anuria and pain in the graft area. Subsequently, serum creatinine levels increased to 810.0 μmol/L. Pelvic CT showed increased vascular density of the transplanted kidney, and contrast-enhanced ultrasound confirmed venous thrombosis. The patient was treated with heparin sodium alone and diuresis gradually resumed. After more than 1 year of follow-up, serum creatinine returned to the baseline level prior to thrombosis. Our case indicates that quick ancillary examination and treatment without hesitation would be indispensable in rescuing allografts with renal vein thrombus. Unfractionated heparin can be recommended as an effective treatment for mid-long-term renal transplantation patients with renal vein thrombosis.

[Surgical outcomes and complications following third kidney transplantation]

BACKGROUND

After two consecutive kidney transplant failures, a third kidney transplantation improves survival for patients on the waiting list. The surgical outcomes and complications of third kidney transplantations remain poorly known.

METHODS

We analyzed the last 100 third kidney transplantations performed in our center between January 2000 and August 2018. The data, relating to donors and recipients, were extracted retrospectively from medical records and from the prospective DIVAT database (computerized and validated data in transplantation). Continuous variables are expressed as means, medians, first and third quartiles (median, [Q1;Q3]). Categorical variables are expressed as percentages. Patient and transplant survivals were calculated using the Kaplan-Meier method.

RESULTS

Mean age of recipients was 46.4 years (47, [36;53]). Thirty-five percent had kidney failure due to urinary tract malformations. Mean age of donors was 48.2 years (52, [39.75; 58]) with 63% of donors with standard criteria. Mean cold ischemia time was 22.4hours (21, [16.5; 29.2]). Surgical mortality rate was 2% and surgical complication rate was 45%. Third kidney transplants survival was 73.1% and 58.8% at 5 years and 10 years. Mortality rate with a functioning transplant was 18%.

CONCLUSION

A third kidney transplant offers satisfactory functional outcomes but remains associated with high morbi-mortality and a significant death rate with a functioning transplant.

LEVEL OF EVIDENCE: 4

Reconstruction of the accessory renal artery with autogenous vessels in aortic hybrid surgery: A case report

OBJECTIVE

Accessory renal artery (ARA) is a common variant of renal vessels. Currently, there are some controversies about reconstruction strategy and few cases reported in the literature. Individualized treatment should be carried out according to preoperative renal function evaluation and technical level.

METHODS

In this paper, a 50-year-old male patient was reported, who developed a dissecting aneurysm after thoracic endovascular aortic repair (TEVAR) and needed further intervention. Imaging showed that the left kidney was supplied by bilateral renal artery (false lumens), and there were left renal malperfusion complicated with abnormal renal function.

RESULTS

Autologous blood vessels were used to successfully reconstruct ARA with during hybrid surgery. Renal perfusion and renal function recovered rapidly after operation. There was no abnormality in renal indexes after 3 months follow-up.

CONCLUSION

It is beneficial and necessary to reconstruct ARA for patients with renal malperfusion or abnormal renal function before operation.

Wireless implantable optical probe for continuous monitoring of oxygen saturation in flaps and organ grafts

Continuous, real-time monitoring of perfusion after microsurgical free tissue transfer or solid organ allotransplantation procedures can facilitate early diagnosis of and intervention for anastomotic thrombosis. Current technologies including Doppler systems, cutaneous O₂-sensing probes, and fluorine magnetic resonance imaging methods are limited by their intermittent measurements, requirements for skilled personnel, indirect interfaces, and/or their tethered connections. This paper reports a wireless, miniaturized, minimally invasive near-infrared spectroscopic system designed for uninterrupted monitoring of local-tissue oxygenation. A bioresorbable barbed structure anchors the probe stably at implantation sites for a time period matched to the clinical need, with the ability for facile removal afterward. The probe connects to a skin-interfaced electronic module for wireless access to essential physiological parameters, including local tissue oxygenation, pulse oxygenation, and heart rate. In vitro tests and in vivo studies in porcine flap and kidney models demonstrate the ability of the system to continuously measure oxygenation with high accuracy and sensitivity.

Although continuous monitoring of tissue oxygenation is critically important after tissue/organ graft procedures, current technologies have key limitations. Here, the authors develop a miniaturized, minimally invasive, self-anchoring optical probe and demonstrate continuous monitoring of oxygenation in porcine flap and organ models.

Safety and Intraoperative Results in Live Kidney Donors with Vascular Multiplicity After Hand-Assisted Laparoscopy Living Donor Nephrectomy

Background and Purpose

Vascular multiplicity is the most frequent anatomic variation in kidney donors. Despite concerns about risks, these allografts are increasingly used to overcome the shortage of kidney donors. The safety and clinical outcomes in living kidney donors were evaluated with vascular multiplicity after hand-assisted laparoscopic living donor nephrectomy (HALDN).

Patients and Methods

Data from all living kidney donors who underwent HALDN from 2008 to 2021 was retrospectively reviewed. Patients were divided into two groups as single (SRV) and multiple renal vessels (MRV), and a comparative analysis was done. The primary outcomes include operating room time (ORT), days of hospital stay, estimated blood loss, complications, conversion, and re-operations.

Results

MRV were present in 166 out of 612 donors (27.1%). Among those, 10 (1.6%) donors had simultaneous multiple arteries and veins. Additionally, the prevalence of artery and vein multiplicity was 21.8% (n = 134) and 3.5% (n = 22), respectively. Warm ischemia time was significantly different among the two groups but not clinically important. The number of conversions to open technique, the mean ORT, the median blood loss, and days of hospital stay were similar between the SRV and MRV groups, without significant differences. According to the modified Clavien-classification system, no differences were found in the complication rates between the two groups (p = 0.29). Complication rates were 3.3% and 3.6% for the SRV and MRV groups, respectively.

Conclusion

HALDN is a procedure with safe intraoperative results, even with vascular multiplicity. The presence of multiple renal arteries or veins has no negative impact on the outcome of the donor after living donor nephrectomy.

Number of Donor Renal Arteries and Early Outcomes after Deceased Donor Kidney Transplantation

Background

Anatomic abnormalities increase the risk of deceased donor kidney discard, but their effect on transplant outcomes is understudied. We sought to determine the effect of multiple donor renal arteries on early outcomes after deceased donor kidney transplantation.

Methods

For this retrospective cohort study, we identified 1443 kidneys from 832 deceased donors with ≥1 kidney transplanted at our center (2006-2016). We compared the odds of delayed graft function and 90-day graft failure using logistic regression. To reduce potential selection bias, we then repeated the analysis using a paired-kidney cohort, including kidney pairs from 162 donors with one single-artery kidney and one multiartery kidney.

Results

Of 1443 kidneys included, 319 (22%) had multiple arteries. Multiartery kidneys experienced longer cold ischemia time, but other characteristics were similar between groups. Delayed graft function (50% multiartery versus 45% one artery, P=0.07) and 90-day graft failure (3% versus 3%, P=0.83) were similar between groups before and after adjusting for donor and recipient characteristics. In the paired kidney analysis, cold ischemia time was significantly longer for multiartery kidneys compared with single-artery kidneys from the same donor (33.5 versus 26.1 hours, P<0.001), but delayed graft function and 90-day graft failure were again similar between groups.

Conclusions

Compared with single-artery deceased donor kidneys, those with multiple renal arteries are harder to place, but experience similar delayed graft function and early graft failure.

Reconstruction of a Lower Polar Artery for Kidney Transplantation Using Donor Ovarian Vein: Case Report with Literature Review

Background: In the case of complicated kidney transplantation, when the accessory artery is severed, the main task is to decide whether to restore renal blood flow and which method should be used. In this report, we present a case of kidney transplantation with vascular reconstruction using an ovarian vein as an interposition graft between a larger branch of the main renal artery and the lower polar artery which was severed during kidney explantation. Case summary: Kidney transplantation using an ovarian vein was performed for a 34-year-old woman with end-stage renal disease on 1 April 2020 in the Hospital of Lithuanian university of health sciences (LUHS) Kaunas Clinics. A lower accessory renal artery was severed during kidney explantation. As the ovarian vein of the donor remained and matched the diameter of the severed vessel, it was decided to use it as an insertion between the main renal artery and the accessory renal artery of the inferior pole. The cold ischemic time was 770 min and the warm ischemic time was 37 min. A month after transplantation, the patient's condition and daily urine output were normal and the serum creatinine level decreased rapidly. Fifteen months after the surgery, the function and structure of the transplant remained normal and there was no evidence of serious vascular complications on CT scans. This is the first case where graft function was verified after transplantation using three-dimensional CT angiography. Conclusions: If an inferior polar artery is severed, vascular reconstruction must be performed to preserve the function of the graft. Usually, the gonadal vein is available during donor nephrectomy; therefore, it can be explanted without additional difficulties or incisions. Although we have not reported any complications, further studies are recommended on the long-term outcomes of this alternative approach for the reconstruction of short renal arteries.

Hip Position Acutely Affects Oxygenation and Perfusion of Kidney Grafts as Measured by Functional Magnetic Resonance Imaging Methods-The Bent Knee Study

Background: Kidney perfusion and oxygenation are two important determinants of kidney graft function. In kidney transplantation, repeated graft hypoperfusion may occur during hip flexion, for example in the sitting position, due to the progressive development of fibrotic tissue around iliac arteries. The aim of this study was to assess the changes in oxygenation and perfusion of kidney grafts during hip flexion and extension using a new functional magnetic resonance imaging (fMRI) protocol. Methods: Nineteen kidney graft recipients prospectively underwent MRI on a 3T scanner including diffusion-weighted, blood oxygenation level dependent (BOLD), and arterial spin labeling sequences in hip positions 0° and >90° before and after intravenous administration of 20 mg furosemide. Results: Unexpectedly, graft perfusion values were significantly higher in flexed compared to neutral hip position. Main diffusion-derived parameters were not affected by hip position. BOLD-derived cortico-medullary R2^* ratio was significantly modified during hip flexion suggesting an intrarenal redistribution of the oxygenation in favor of the medulla and to the detriment of the cortex. Furthermore, the increase in medullary oxygenation induced by furosemide was significantly blunted during hip flexion (p < 0.001). Conclusion: Hip flexion has an acute impact on perfusion and tissue oxygenation in kidney grafts. Whether these position-dependent changes affect the long-term function and outcome of kidney transplants needs further investigation.

Is intraoperative heparin during renal transplantation useful to reduce graft vascular thrombosis?

OBJECTIVES

The standard treatment for end-stage renal disease is renal transplantation. As vascular anastomoses are performed during the surgery, it may expose to a risk of vascular thrombosis. This raises the question of using intravenous heparin during the procedure. The purpose of this study was to compare the incidence of renal transplant vascular thrombosis in the perioperative period based on whether the patients received or not intraoperative heparin.

METHODS

A single center retrospective study was conducted on a cohort of consecutive patients who underwent renal transplantation between 2011 and 2015. Patients were divided into two groups: patients not receiving heparin vs. receiving heparin at the dose of 0.5mg/kg. A Doppler ultrasound was performed at day one postoperatively to assess the occurrence of vascular thrombosis. Hemorrhagic complications and the need for postoperative transfusion were also assessed.

RESULTS

In total, 261 patients were included. Fifty-one patients received heparin (19.5%). Patient's baseline characteristics were comparable between the groups. No significant difference was found regarding the incidence of vascular thrombosis (6% for both groups, P=1). In addition, no difference was found regarding hemorrhagic complications requiring surgical revision (P=1) as well as early postoperative transfusion rate (P=0.57).

CONCLUSIONS

Our results suggest that intraoperative IV heparin doesn't improve the risk of vascular thrombosis following renal transplantation. However, intraoperative IV heparin was not significantly associated with a higher rate of hemorrhagic complications suggesting that heparin can be safely used if required in some selected patients at higher risk of thrombosis.

LEVEL OF EVIDENCE

3.

Retrospective Analysis of the Comparison Between Single Renal Artery Versus Multiple Renal Arteries in Living Donor Kidney Transplant: Does It Affect the Outcome?

OBJECTIVES

There is an increased risk of vascular complications in kidney transplant for allografts with multiple renal arteries versus a single renal artery. We compared the clinical outcomes of living donor kidney transplant recipients who received allografts with a single renal artery versus multiple renal arteries.

MATERIALS AND METHODS

This retrospective analysis included all living-related donor kidney transplants that were performed by a single skilled urologist. All donor nephrectomies were performed by open method. The left kidney was preferred over the right for donor nephrectomy, except in cases of vascular problems or other contraindications, for which the right kidney was preferred. In most of the cases, kidneys were placed in the right iliac fossa for transplant by an extraperitoneal approach.

RESULTS

Of 97 living donor kidney transplants, 82 had a single renal artery (group 1) and 15 had multiple renal arteries (group 2). Patients ranged in age from 18 to 76 years old. Recipient ages (33.00 vs 29.46 years) and baseline serum creatinine values (8.61 vs 8.82 mg/dL) were comparable in groups 1 and 2 (P > .05). However, mean operative time and total ischemia time were significantly higher in the multiple renal artery group (221 and 53.45 minutes, respectively) compared with the single renal artery group (202 and 77.6 minutes, respectively). Graft survival at 1 year was 95.12% in the single renal artery group and 93.33% in the multiple renal artery group. Patient survival at 1 year was 96.34% in the single renal artery group and 93.33% in the multiple renal artery group.

CONCLUSIONS

The safety of kidney transplants of allografts with multiple renal arteries is equal to the safety of transplants of allografts with a single renal artery in terms of vascular complications and acute tubular necrosis, as well as patient and graft survival.

Grafts With Multiple Renal Arteries in Kidney Transplantation

BACKGROUND

Renal grafts with multiple renal arteries (MRA) are a compelling issue in surgery of kidney transplantation. Transplantations using "grafts with MRA" have conflicting results. Here, we present our experiences on the issue.

METHOD

This is a single-center, observational, descriptive study. One hundred ninety-nine patients with end-stage renal disease received a kidney graft from their living- or deceased-related donors in our center between July 2016 and May 2017. We included all recipients to the study. Patients were divided into the following 2 groups: Group 1, recipients who received a renal graft with single renal artery, and Group 2, recipients who received a renal graft with MRA. Groups were compared for estimated glomerular filtration rates (months 1-3 and 12), delayed graft function, and graft survival. Data were analyzed by using SPSS for Windows version 15.

RESULTS

One hundred ninety-five recipients with all documented data were analyzed. Graft function was compared between 2 groups in months 1, 3, and 12 and found both to have similar outcomes. MRA has been indicated to have no impact on delayed graft function, higher risk for vascular injury, and biopsy-proven acute tubular necrosis. Also, anastomosis sides have been found to have no importance on graft function in recipients with MRA (P > .05 between all sides).

CONCLUSION

Our study indicates grafts with MRA and grafts with a single renal artery have comparable results in the first post-transplant year.

Risk Factors for Graft Loss Due to Acute Vascular Complications in Adult Renal Transplantation Using Grafts Without Vascular Anomalies

BACKGROUND

Vascular complications are the main cause of early graft loss in renal transplant (RT). A graft with multiple vessels represents the most validated risk factor. The aim of the present study was to identify potential predictive factors for acute vascular complications causing graft loss when graft vascular anomalies are excluded.

METHODS

This is a retrospective case-control (1:3 ratio) study extrapolated from the RT series of the Renal Transplant Unit - Udine University Hospital, during the period 1993-2017. Grafts with multiple vessels and retransplant cases were excluded.

RESULTS

The overall prevalence of graft loss due to acute vascular complications was 2.6% (25/961). Seventeen complicated recipients had grafts without vascular anomalies (case group). The median time between RT and complication was 6 days (interquartile range, 4-23 days). The following types of vascular complications were recorded: 5 isolated renal artery thromboses (0.5%), 4 isolated renal vein thromboses (0.4%), 4 combined renal artery and vein thromboses (0.3%), 3 renal artery ruptures due to mycotic arteritis (0.3%), and 1 renal artery nonmycotic pseudoaneurysm (0.1%). No differences were recorded between the groups in terms of donors and grafts characteristics. Complicated recipients showed a statistically higher prevalence of thromboembolism history (P = .046) and vascular atherosclerosis (P = .048). During the postoperative course, blood stream infections (P = .02), acute rejection (P = .03), bleeding from a nonmacrovascular source (P = .04), and multiple reintervention because of nonvascular complications (P = .03) were identified as significant risk factors.

CONCLUSIONS

Recipient characteristics and post-RT complications rather than donor and graft characteristics are relevant risk factors for graft loss due to acute vascular complications when graft vascular anomalies are excluded.

Human uterine transplantation: a review of outcomes from the first 45 cases

Uterine transplantation restores reproductive anatomy in women with absolute uterine factor infertility and allows the opportunity to conceive, experience gestation, and acquire motherhood. The number of cases being performed is increasing exponentially, with detailed outcomes from 45 cases, including nine live births, now available. In light of the data presented herein, including detailed surgical, immunosuppressive and obstetric outcomes, the feasibility of uterine transplantation is now difficult to refute. However, it is associated with significant risk with more than one-quarter of grafts removed because of complications, and one in ten donors suffering complications requiring surgical repair. TWEETABLE ABSTRACT: Uterine transplantation is feasible in women with uterine factor infertility, but is associated with significant risk of complication.

Analysis of the Effects of Day-Time vs. Night-Time Surgery on Renal Transplant Patient Outcomes

Sleep deprivation and disruption of the circadian rhythms could impair individual surgical performance and decision making. For this purpose, this study identified potential confounding factors on surgical renal transplant patient outcomes during day and night. Our retrospective cohort study of 215 adult renal cadaver transplant recipients, of which 132 recipients were allocated in the “day-time” group and 83 recipients in the “night-time” group, primarily stratified the patients into two cohorts, depending on the start time. Within a 24 h operational system, “day-time” was considered as being from 8 a.m. to 8 p.m. and “night-time” from 8 p.m. to 8 a.m.. Primary outcomes examined patient and graft survival after three months and one year. Secondary outcomes included the presence of acute rejection (AR) and delayed graft function (DGF), as well as the rate of postoperative complications. In log-rank testing, “day-time” surgery was associated with a significantly higher risk of patient death (p = 0.003), whereas long-term graft survival was unaffected by the operative time of day. The mean cold ischemia time (CIT), which was 12.4 ± 5.3 h in the “night-time” group, was significantly longer compared to 10.7 ± 3.6 for those during the day (p = 0.01). We observed that “night-time” kidney recipients experienced more wound complications. From our single-centre data, we conclude that night-time kidney transplantation does not increase the risk of adverse events or predispose the patient to a worse outcome. Nevertheless, further research is required to explore the effect of fatigue on nocturnal surgical performance.

Outcomes of Kidney Transplantation by Using the Technique of Renal Artery Anastomosis First

Introduction

The surgical technique for kidney transplantation has been well established: the renal vein is anastomosed first, followed by renal artery anastomosis. Alternatively, the renal artery can be anastomosed first and then the renal vein for kidney transplantation. However, there is a lack of data on the outcomes of kidney transplantation by using this alternative approach. The objective of this paper was to review the outcomes of kidney transplant by using this approach.

Methods

A review of 205 consecutive kidney transplants was conducted. All kidney transplants were performed by doing renal artery anastomosis first and then the renal vein. Data were collected, including vascular/urological complications and kidney graft function.

Results

All transplants were performed successfully with no occurrence of renal artery/vein thrombosis and urine leakage. There were five cases of renal artery stenosis that were managed with endovascular intervention. There was no recurrence on follow-up. One ureteric stenosis required surgical reconstruction.

Conclusions

This alternative vascular anastomotic technique is efficient and safe. It avoids flip-flopping the kidney graft during the vessel anastomoses and may be more practical in minimally invasive surgery for a kidney transplant due to the space constraint.

Preoperative Risk Factors Associated With Urinary Complications After Kidney Transplantation

BACKGROUND

Only surgically irrelevant risk factors including sex, African-American ancestry, or exceptional U-stitch anastomosis have been identified to associate with urinary complications after kidney transplantation. The objective was to identify modifiable and nonmodifiable risk factors associated with urinary complications after kidney transplantation.

METHODS

A single-center study of 3,129 kidney transplants performed over 40 years was conducted to identify independent risk factors using χ² tests and logistic regression analysis.

RESULTS

We identified the quality of the transplant's ureter, cystographic abnormalities in the recipient, and repeat transplantations as independent risk factors for overall urinary complications occurring after kidney transplantation in multivariable analysis. Obesity was associated with an increased risk of urinary fistula, while the presence of a JJ stent was associated with a reduced risk of urinary fistula. The risk of urinary surgical complications for kidney transplantations was reduced when the kidney was recovered from a living related compared to a deceased donor.

CONCLUSIONS

The risk factors identified in the present study will allow candidates for kidney transplantation to be more informed and will also allow for surgical modifications to limit the occurrence of urinary complications.

Reconstruction of a Damaged Lower Polar Artery for Kidney Transplantation Using Tubularised Donor Aorta

Introduction

Live donors, extended donor criteria, and the maximum usage of organs with anatomical variants are some of the mechanisms used to increase the number of organs available.

Case

We present the case of a kidney transplant, in which the organ had an iatrogenic injury to a lower pole arterial branch during retrieval. The donor was a 35-year-old male (DCD, Maastricht III). The right kidney was accepted; it had three veins in a single cava patch and three renal arteries, the main artery with aorta patch that is 8 cm long. A small lower pole artery was sectioned during retrieval surgery at approximately 1 cm from its origin as well as a third small mid-lower pole artery. The lower pole damaged artery was reconstructed using tubularised aorta patch to a total length of 5 cm. No additional donor vessels had been sent. After construction of the tubulised aorta, E-E anastomosis to the damaged polar artery was done with interrupted 7-0 Prolene sutures.

Conclusion

While the waiting list for a kidney continues to rise and we continue to have organ shortness, vascular retrieval injury should not be an absolute contraindication for transplant.

Clinical Impact of Surgical Complications in Kidney Transplant Recipients in a Reference Hospital in Salvador, Bahia, Brazil

BACKGROUND

Renal transplantation is the treatment of choice for patients with stage V chronic kidney disease, which does not have contraindications to the procedure and is more cost-effective than dialysis treatments and provides better survival and quality of life.

OBJECTIVE

The objective of this study was to evaluate the incidence of postoperative complications in kidney transplant recipients in a reference hospital.

METHODOLOGY

This was a descriptive and retrospective study involving the analysis of patient records during hospitalization and outpatient treatment. We analyzed the demographics, clinical indicators, surgical techniques, and postoperative complications.

RESULTS

In the analysis of 147 transplantations, there was a higher incidence of transplantation in female recipients, average age of 37 years with a predominance of cadaveric transplantation. Of all pretransplantation comorbidities, hypertension was the most frequent. The overall incidence of surgical complications was 29.9%, with an incidence of vascular complications of 12.7%, 13.4% of surgical site complications, 8.2% of urologic complications, and 3% of hemorrhagic complications.

DISCUSSION

Vascular complications are serious complications and are associated with increased risk of graft loss (relative risk, 8.4), particularly arterial thrombosis. Patients with ureteral anastomosis using Lich-Gregoir technique showed lower urologic complications compared with patients with anastomosis by Leadbetter-Politano technique.

CONCLUSION

Surgical complications have different clinical effects, depending on their category. The vascular complications are associated with graft lost.

Impact of ultrasound examination shortly after kidney transplantation

Background

Ultrasound is routinely performed at our transplant unit within the first 48 h of kidney transplantation (KTX). The objective of this study was to evaluate the association of ultrasound results and, in particular, elevated resistance indices (RIs) with the occurrence of surgical complications and allograft outcomes.

Methods

The study included all kidney allograft recipients undergoing transplantation at our center between January 2010 and December 2011 (N = 329). Ultrasound examination was performed on 315 recipients (95.7%).

Results

Delayed graft function was more common in subjects with a high RI (≥0.7) than in patients with an RI < 0.7 (47.2 vs. 28.2%; p = 0.032). A lack of arterial signal was detected in eight patients (2.5%), of whom five had a vascular complication that required surgical therapy. In 12 patients (3.8%), RI was 1 without any other signs of vascular impairment. Even though such values can be a sign of venous thrombosis, no case was observed in any of these patients.

Conclusions

The results of our study suggest that ultrasound evaluation of the transplanted kidney shortly after transplantation is a valuable tool not only for detecting vascular complications but also as a predictor of graft outcome regarding delayed graft function.

5 Years Experience With Drug Eluting and Bare Metal Stents as Primary Intervention in Transplant Renal Artery Stenosis

Background

Transplant renal artery stenosis (TRAS) is a common vascular complication after kidney transplantation and is associated with refractory hypertension, volume overload, and graft injury or loss. This article describes 5-year outcomes of endovascular intervention for TRAS with bare metal and drug eluting stents (DES).

Methods

We investigated, as a prospective cohort study, patient and graft outcomes after the targeted use of DES for vessel diameter less than 5 mm and bare metal stents (BMS) for vessel diameter greater than 5 mm as the primary management for TRAS.

Results

From March 2008 to November 2014, 57 patients were stented for hemodynamically significant TRAS; 29 received DES, 26 received BMS, and 2 patients received both stent types. They were followed up for a mean of 35.1 ± 22.8 months; a subset of these patients who all received DES were followed up for 61.7 ± 17.5 months. Mean serum creatinine declined from 2.87 ± 1.5 mg/dL at the time of intervention to 1.98 ± 0.76 mg/dL (P < 0.001) at one month follow-up and was 1.96 ±0.92 mg/dL (P < 0.001) at 35.1 ± 22.8 months. Mean systolic blood pressure declined from 159.05 ± 19.68 mm Hg at time of intervention to 135.65 ± 15.10 mm Hg (P < 0.001) at most recent visit. Clinically driven restenosis requiring repeat revascularization occurred in 15.7% of patients.

Conclusions

Primary stenting with DES and BMS is both successful in the initial treatment of TRAS and also produced an immediate and long-term reduction in serum creatinine and systolic blood pressure.

Vascular Multiplicity Should Not Be a Contra-Indication for Live Kidney Donation and Transplantation

BACKGROUND

Whether vascular multiplicity should be considered as contraindication and therefore 'extended donor criterion' is still under debate.

METHODS

Data from all live kidney donors from 2006-2013 (n = 951) was retrospectively reviewed. Vascular anatomy as imaged by MRA, CTA or other modalities was compared with intraoperative findings. Furthermore, the influence of vascular multiplicity on outcome of donors and recipients was studied.

RESULTS

In 237 out of 951 donors (25%), vascular multiplicity was present. CTA had the highest accuracy levels regarding vascular anatomy assessment. Regarding outcome of donors with vascular multiplicity, warm ischemia time (WIT) and skin-to-skin time were significantly longer if arterial multiplicity (AM) was present (5.1 vs. 4.0 mins and 202 vs. 178 mins). Skin-to-skin time was significantly longer, and complication rates were higher in donors with venous multiplicity (203 vs. 180 mins and 17.2% vs. 8.4%). Outcome of renal transplant recipients showed a significantly increased WIT (30 vs. 26.7 minutes), higher rate of DGF (13.9% vs. 6.9%) and lower rate of BPAR (6.9% vs. 13.9%) in patients receiving a kidney with AM compared to kidneys with singular anatomy.

CONCLUSIONS

We conclude that vascular multiplicity should not be a contra-indication, since it has little impact on clinical outcome in the donor as well as in renal transplant recipients.

Evaluation of the Vascular Surgical Complications of Renal Transplantation

BACKGROUND

Renal transplantation is the treatment of choice of end-stage renal failure. However, vascular surgical complications can compromise the functional prognosis of the transplant or even be life threatening in the short term. Since few data are available in the literature, the objective of this study was to evaluate the vascular surgical complications of renal transplantation.

METHODS

In a retrospective and monocentric study, the records of all the patients receiving a kidney transplant between January 2008 and December 2014 were reviewed. The demographic data and the follow-up of the patients who presented a vascular surgical complication in relation to their transplant were collected. Minor, intermediate, or major vascular complications were defined according to the need for monitoring, reoperation, or the risk of transplant loss or a life-threatening situation. Predictive factors of vascular complications were also looked for.

RESULTS

Mean age was 50.9 ± 15.0 years, and 312 kidney transplants were carried out (205 men). Fifty vascular surgical complications (16.0%) were found. Among them, 23 vascular complications (7.4%) were major, including 6 (1.9%) which required transplantectomy, after 4 arterial thromboses (1.3%), 1 early venous thrombosis (0.3%), and 1 injury of the inferior vena cava (0.3%). Twelve complications (3.8%) were minor. Surgical revision was necessary in 76% of the vascular complications (n = 38). The average follow-up of the transplanted population was 37.4 ± 24.0 month, 268 kidney transplants (85.8%) were functional and 21 patients (6.7%) returned to dialysis. Surgical complications were more frequent when the recipient had hypertension (P = 0.02, OR = 2.5; 95% CI [1.1-6.1]), in case of right kidney transplant (P = 0.0004, OR = 3.1; 95% CI [1.6-5.8]) and when the kidney hilum consisted of at least arteries (P = 0.02, OR = 10.0; 95% CI [1.3-34]). Male gender (P = 0.03, OR = 0.5; 95% CI [0.3-0.9]) as well as the choice of the common iliac arterial (P = 0.001, OR = 0.4; 95% IC [0.2-0.7]) and venous (P = 0.002, OR = 0.3; 95% IC [0.2-0.8]) axes to carry out the vascular anastomoses appeared as protective factors.

CONCLUSIONS

The vascular surgical complications of kidney transplantation, especially thromboses, can be serious and lead to transplant loss. The expertise of vascular surgeons finds its place here and makes it possible to maintain low rates of vascular complications and loss of transplants.

Lymphocele after pediatric kidney transplantation: incidence and risk factors

Lymphocele is a well-known postoperative complication after kidney transplantation. The aim of this study was to analyze time trend incidence, risk factors, and outcome of post-transplant lymphocele in a large pediatric cohort. This is a retrospective single institution review of 241 pediatric kidney transplants performed from 2000 to 2013. Etiology of end-stage renal disease, recipient age and gender, transplant year, BMI percentile for age, type of dialysis, living/non-living related donor, acute rejection, and multiple transplantations were analyzed in association with lymphocele formation. Fourteen of 241 (5.81%) children developed a postoperative lymphocele. There has been a reduction in the incidence of lymphocele after 2006 (3.22% vs. 8.55%, p < 0.05). Significant risk factors for lymphocele were older age (≥11 yr), transplant before 2006, male gender, BMI percentile for age ≥95%, and multiple transplantations (p < 0.05). The one-yr graft survival was significantly reduced in the group with lymphocele compared with control (81.2% vs. 92.51%, p < 0.04). This is the first pediatric report showing the following risk factors associated with post-transplant lymphocele: age ≥11 yr, male gender, BMI for age ≥95%, and multiple transplantations. A lymphocele can contribute to graft loss in the first-year post-transplant.

Near-infrared spectroscopy as continuous real-time monitoring for kidney graft perfusion

BACKGROUND

Near-infrared spectroscopy (NIRS) is a non-invasive technique designed to study regional oxygenation (rSO(2)) by measuring the absorption of chromophores. This study investigated the role of NIRS in the real-time monitoring of kidney graft perfusion for 72 h post-transplantation.

METHODS

Consecutive children undergoing living related donor (LRD) or deceased donor (DD) kidney transplantation (KTP) were prospectively enrolled between April 2010 and August 2011. Renal rSO(2) values were registered continuously for 3 days and correlated with hourly urine output, serum creatinine, and urinary neutrophil gelatinase-associated lipocalin (u-NGAL).

RESULTS

Twenty-four children were included, 6 underwent LRD and 18 DD KTP. Median age was 12.5 years (interquartile range [IQR] 3.5-16.6) and median body weight was 37 kg (IQR 13-49.7). Four patients experienced delayed graft function (DGF). Renal Doppler ultrasound showed normal vascularization patterns in all children. Median basal renal rSO(2) value was 68.8 % (IQR 59.3-76.2), significantly lower than the end-of-period result (83.6 %; IQR 79.2-90.4; p < 0.0001). Renal rSO(2) values showed significant correlation with serum creatinine (rs = -0.62; p < 0.05) and estimated glomerular filtration rate (eGFR) (rs = 0.64; p < 0.05). No correlation was shown between rSO(2) and diuresis. Increased rSO(2) was also found in patients who experienced DGF. u-NGAL exhibited a trend toward a decrease from baseline in both DD and LRD KTPs, with a strong negative correlation with rSO(2).

CONCLUSIONS

rSO(2) assessed by NIRS strongly correlates with common markers of kidney graft function and perfusion, allowing continuous real-time monitoring of blood flow in renal grafts.

Shifting paradigms in eligibility criteria for live kidney donation: a systematic review

As the organ shortage increases, inherently the demand for donor kidneys continues to rise. Thus, live kidney donation is essential for increasing the donor pool. In order to create successful expansion, extended criteria live kidney donors should be considered. This review combines current guidelines with all available literature in this field, trying to seek and establish the optimal extended criteria. Comprehensive searches were carried out in major databases until November 2013 to search for articles regarding older age, overweight and obesity, hypertension, vascular anomalies/multiplicity, nulliparous women, and minors as donors. Of the 2079 articles found, 152 fell within the scope of the review. Five major guidelines were included and reviewed. Based on the literature search, live kidney donation in older donors (up to 70 years of age) seems to be safe as outcome is comparable to younger donors. Obese donors have comparable outcome to lean donors, in short- and mid-term follow-up. Since little literature is available proving the safety of donation of hypertensive donors, caution is advised. Vascular multiplicity poses no direct danger to the donor and women of childbearing age can be safely included as donors. Although outcome after donation in minors is shown to be comparable to adult donors, they should only be considered if no other options exist. We conclude that the analyzed factors above should not be considered as absolute contraindications for donation.

Intra-arterial ultra low iodine CT angiography of renal transplant arteries

PURPOSE

This study was designed to evaluate the technical feasibility and the image quality of intra-arterial 320-row CT angiography (ia-CTA) in the detection of transplant renal artery stenosis (TRAS) using a very low dose of contrast agent.

METHODS

Evaluation of ia-CTA using a 4F catheter in ten patients with impaired renal transplant function and suspected TRAS. Average amount of contrast agent applied was 10 ± 3.7 ml standard deviation (SD). Patient serum creatinine levels had been monitored for 72 h. TRAS was detected and graded (1: less than 20 %; 2: 20-49 %; 3: 50-74 %; 4: 75-99 %; 5: total occlusion) and presence of kinking was recorded. Attenuation and vessel delineation were parameters for image quality analysis of the renal arterial supply, divided into four segments. Subjective image quality.

RESULTS

Ia-CTA of the renal transplant was technically successful in all patients, revealing relevant stenoses in 7 of 10 patients. Serum creatinine levels before and after ia-CTA were 2.71 ± 1.46 and 2.56 ± 1.39 mg/dl, respectively. None of the patients developed signs of contrast-induced nephropathy within 72 h. Subjective image quality was excellent in all four segments, rated by two separate readers. No segment was found to be nondiagnostic. Mean attenuation values in the arterial segments ranged between 754 and 987 Hounsfield units.

CONCLUSIONS

Wide detector ia-CTA for the diagnosis of TRAS is feasible using very low doses of contrast agent and results in high image quality.

Renal autotransplant for subsequent endovascular exclusion of the thoracoabdominal aorta

In the last 20 years, endovascular procedures have radically altered the treatment of diseases of the aorta. The objective of endovascular treatment of dissections is to close the entry point to redirect blood flow toward the true lumen, thereby achieving thrombosis of the false lumen. In extensive chronic dissections that have evolved with the formation of a large aneurysm, the dissection is maintained from the end of the endoprosthesis due to multiple orifices, or reentries, that communicate with the lumens. In addition, one of the primary limitations of this technique is when the visceral arteries have disease involvement. In this report we present a case where, despite having treated the entire length of the descending thoracic aorta, the dissection was maintained distally, leading to progression of the diameter of the aneurysm. After reviewing the literature, and to the best of our knowledge, we describe the first case in which renal autotransplant was performed to allow for subsequent exclusion of the aorta at the thoracoabdominal level using a fenestrated endoprosthesis for the celiac trunk and the superior mesenteric artery.