Assessment of Individualized Mean Perfusion Pressure Targets for the Prevention of Cardiac Surgery-Associated Acute Kidney Injury-The PrevHemAKI Randomized Controlled Trial

BACKGROUND

Retrospective studies support that mean perfusion pressure (MPP) deficit in cardiac surgery patients is associated with a higher incidence of acute kidney injury (CS-AKI). The aim of our study was to apply an algorithm based on MPP in the postoperative period to determine whether management with an individualized target reduces the incidence of CS-AKI.

METHODS

Randomized controlled trial of patients undergoing cardiac surgery with extracorporeal circulation. Adult patients submitted to valve replacement and/or bypass surgery with a high risk of CS-AKI evaluated by a Leicester score >30 were randomized to follow a target MPP of >75% of the calculated baseline or a standard hemodynamic management during the first postoperative 24 h.

RESULTS

Ninety-eight patients with an eGFR of 54 mL/min were included. There were no differences in MAP and MPP in the first 24 h between the randomized groups, although a higher use of noradrenaline was found in the intervention arm (38.78 vs. 63.27, p = 0.026). The percentage of time with MPP < 75% of measured baseline was similar in both groups (10 vs. 12.7%, p = 0.811). MAP during surgery was higher in the intervention group (73 vs. 77 mmHg, p = 0.008). The global incidence of CS-AKI was 36.7%, being 38.6% in the intervention group and 34.6% in the control group (p = 0.40). There were no differences in extrarenal complications between groups as well.

CONCLUSION

An individualized hemodynamic management based on MPP compared to standard treatment in cardiac surgery patients was safe but did not reduce the incidence of CS-AKI in our study.

Bariatric Surgery Outcomes in Patients with Chronic Kidney Disease

Obesity increases the risk of developing chronic kidney disease (CKD), which has a major negative impact on global health. Bariatric surgery (BS) has demonstrated a substantial improvement of obesity-related comorbidities and thus, it has emerged as a potential therapeutic tool in order to prevent end-stage renal disease. A limited number of publications to date have examined the beneficial effects and risks of BS in patients with non-advanced stages of CKD. We aimed to investigate the safety of BS in patients with CKD stages 3-4 (directly related or not to obesity) and both the metabolic/renal outcomes post-BS. A total of 57 individuals were included (n = 19 for CKD-group; n = 38 for patients with obesity, but normal eGFR [control-group]). Weight loss and obesity comorbidities resolution after BS were similar in both groups. Renal function (eGFR [CKD-EPI]) improved significantly at the 1-year follow-up: Δ10.2 (5.2-14.9) (p < 0.001) for CKD-group and Δ4.0 (-3.9-9.0) mL/min/1.73 m2 (p = 0.043) for controls. Although this improvement tended to decrease in the 5-year follow-up, eGFR remained above its basal value for the CKD-group. Noteworthy, eGFR also improved in those patients who presented CKD not directly attributed to obesity. For patients with CKD, BS appears to be safe and effective regarding weight loss and obesity comorbidities resolution, irrespective of the main cause of CKD (related or not to obesity).

MO783: Reduction of the Incidence of Dialysis Catheter-Associated Bacteraemia in Intensive Care Units after Systematic Application of Taurolock in the Sealing of the Catheter

BACKGROUND AND AIMS

Dialysis catheter-associated bacteraemia in Intensive Care Units (ICUs) increases morbidity and mortality, prolongs hospital admission and increases admission costs. TauroLock™ is a lock solution containing (cyclo)-taurolidine (1.35%) and citrate (4%). (Cyclo)-taurolidine has broad antimicrobial activity against gram-positive and gram-negative bacteria and fungi. The objective of this study was to analyse the effect of systematic sealing of haemodialysis catheters in the ICUs of the Hospital Clínic de Barcelona on the incidence of bacteraemia associated with haemodialysis catheters (BACH).

METHOD

BACH episodes of patients who underwent intermittent haemodialysis (IHD) during ICU admission were reviewed. The period analysed as pre-Taurolock™ was from 2010 to 2014 and post-TauroLock™ from 2015 to 2018. Patients who only received renal replacement therapy with continuous techniques were excluded.

RESULTS

A total of 279 patients received IHD in the pre-TauroLock™ period and 331 in the post-TauroLock™ period. The number of BACH in the pre-TauroLock™ period was 18 (6.45%) and 9 (2.72%) in the post-TauroLock™ period. All infections were from percutaneous catheters (acute patients) except three catheters that were tunnelled. In the pre-TauroLock™ period, femoral catheters predominated (61.1%) while in the post-TauroLock they were jugular (66.7%). There was no association between the location of the catheter and the incidence of BACH. Of the 27 patients with BACH, 14 (51.8%) were men with a mean age of 63 years, with no significant differences between the two groups. The most frequent reasons for admission to the ICU in the pre-TauroLock™ period were post-cardiac surgery, cardiogenic, septic or hypovolemic shock and acute myocardial infarction (3 patients per group) and in the post-TauroLock™ period, septic shock and pancreatitis (3 and 2 patients respectively). The most frequent isolated bacteria were Gram-positive (in total 48.38%: pre-TauroLock™ 47.61% and post-TauroLock™ 50%), with a global predominance of staphylococcus epidermidis (32.25%) (Table). There were no significant differences in the median days from the start of haemodialysis to bacteraemia (23.5 pre-TauroLock™ versus 21 post-TauroLock™). There were also no significant differences between the days of ICU stay in the BACH in both groups or in mortality, being the overall mortality of 70.4%.

CONCLUSION

In our cohort, the systematic application of TauroLock™ in the sealing of dialysis catheters in critically ill patients reduces the incidence of BACH in ICUs.

Impact of insulin therapy before donation on graft outcomes in pancreas transplantation: An analysis of the OPTN/UNOS database

AIMS

Information on the impact of insulin therapy before pancreas donation on pancreas outcomes is scarce. We aim to explore the influence of insulin therapy before donation on recipient and pancreas graft survival.

METHODS

Registry study including 12,841 pancreas recipients from the OPTN/UNOS registry performed between 2000 and 2017. Inverse probability of treatment weighting (IPTW) was used to account for covariate imbalance between recipients from a donor with and without insulin requirements.

RESULTS

A total of 7765 (60%) patients received a pancreas from a donor with insulin before donation (IBD). Pancreas graft survival (death-censored) was similar between recipients from IBD and non-IBD donors at 1, 5 and 10 years (89% vs 89%, 78% vs 79 and 69% vs 70%, respectively, P = 0.35). Recipients from IBD donors presented a similar 90-days pancreas graft survival. After IPTW weighting, IBD donors were neither associated with any post-transplant surgical complication (HR 1.11 [95% CI 0.98-1.24], P = 0.06), nor with risk for recipient death (HR 0.94 [95% CI 0.85-1.04], P = 0.26), nor pancreas graft failure (HR 1.06 [95% CI 0.98-1.16], P = 0.15).

CONCLUSIONS

Insulin therapy before donation in accepted pancreas donors was not associated, per se, with an impaired pancreas graft and patient survival.

MO929KIDNEY TRANSPLANTATION IN MONOCLONAL IMMUNOGLOBULIN DEPOSITION DISEASE: A REPORT OF 6 CASES

Background and Aims

Monoclonal immunoglobulin deposition disease (MIDD) is a systemic rare condition that usually leads to end stage renal disease. Treatment of patients with a bortezomib-based regimen followed by autologous stem cell transplantation (ASCT) has been increasingly used, with improvements in the response rates and the renal graft outcomes in kidney transplant recipients

Method

Retrospective study of 6 patients diagnosed of MIDD with complete response but not renal response after hematologic treatment that underwent kidney transplant in our institution between 2010 and 2019.

Results

A total of 6 patients (5 women) were analyzed, with mean age at diagnosis of 47 years (range 40-53). At presentation their mean eGFR was 18 mL/minute (range 9-25) and mean proteinuria of 5.5 g (range 0.290-12.5). The deposit was kappa type except in 1 case (heavy and light lambda type chains). In all of them there was an absence of monoclonal component in blood and urine but positive immunofixation in 5 cases (2 only in urine). 3 started chronic hemodialysis during admission and the others at 3, 5 and 44 months after diagnosis. As hematological treatment, all received bortezomib followed by ASCT, being under complete hematological response at the time of kidney transplant. It was performed at 28 months on average from ASCT (range 11-42), with mean kappa/lambda ratio of 2.6 (range 1.33-3.75). 3 patients received induction with thymoglobulin and 3 with basiliximab, followed by triple therapy with tacrolimus + prednisone + mTOR inhibitor (4 patients) or mycophenolate (2 patients). During a median follow-up of 20,5 months from kidney transplant and 54 months from ASCT, 1 patient experienced hematologic relapse and 2 had hematologic progression (one of them with MIDD relapse in the allograft) requiring treatment. The patient with organ relapse received Daratumumab monotherapy achieving complete hematologic response but graft failure. The other 5 patients had functional graft with median serum creatinine 1.68 mg/dl.

Conclusion

In patients with MIDD and sustained complete hematologic response, a kidney transplant can be considered. The optimal approach to treatment of hematologic relapse or recurrence of MIDD after kidney transplant remains to be determined

P1761SIDE EFFECTS OF MTOR INHIBITORS DEPEND ON THE BASELINE METABOLIC STATUS OF KIDNEY TRANSPLANT RECIPIENTS

Background and Aims

Biologically, the cellular activity of the mTOR complexes depends on the balance between the catabolic and the anabolic inputs. Hence, we hypothesized that the metabolic side effects of mTOR inhibitors (mTORi) in kidney transplantation depend on the baseline metabolic status of the patient.

Method

The analysis included all the patients that have been transplanted in our Center between June 2013 to December 2016, completed one year of follow-up and did not change medication during the first year after kidney transplantation (per-protocol population, n=298). Outcomes chosen include de novo diabetes, 1-year difference from baseline in glycated hemoglobin (HbA1c), triglycerides and total cholesterol. Kidney transplant recipients were treated either with an mTORi (either Sirolimus or Everolimus, n=134) or Mycophenolic Acid (MPA, n=164). Both drugs were always accompanied by tacrolimus and steroids. Patients were stratified according to the treatment received (mTORi versus MPA) and the baseline metabolic status (diabetes mellitus type 2 and obesity). Differences among groups were analyzed with exact Fisher test and ANOVA test with LSD post-hoc analysis.

Results

We observed a strong difference for 1-year change in HbA1c depending on the baseline metabolic status of the patients (P&lt;0.001 between groups, Figure 1a). The worst results were observed for patients with baseline diabetes. Among these, obese patients treated with mTORi had the higher increase in HbA1c (3.04 ± 1.18% from baseline, P&lt;0.01 with all groups at post-hoc analysis). De-novo diabetes was more frequent in patients taking mTORi (23.4 vs. 13.1%), albeit not significantly (P=0.100) and without differences taking into account obesity as a covariate. Triglycerides increased substantially in patients without baseline diabetes and treated with mTORi (P&lt;0.05). Surprisingly, in diabetic patients no differences were observed in triglycerides between mTORi and MPA groups (Figure 1b). There were no differences in the increase in total cholesterol among groups (P=0.155) (Figure 1c).

Conclusion

We observed that the 1-year increase in HbA1c and triglycerides attributable to mTORi after kidney transplantation depends on the baseline metabolic status of the patients. We propose that the metabolic side effects of mTORi depend on the balance between anabolic and catabolic inputs of every kidney transplant recipient.

Cardiovascular risk factors and cardiovascular disease in patients with type 1 diabetes and end-stage renal disease candidates for kidney-pancreas transplantation: Trends from 1999 to 2017

AIMS

To evaluate the changes in cardiovascular risk factors (CVRFs) and cardiovascular disease (CVD) in patients with type 1 diabetes (T1D) and end-stage renal disease (ESRD) who were candidates for kidney-pancreas transplantation (KPTx) from 1999 to 2017.

METHODS

Patients with T1D referred for KPTx evaluation were included. The cohort was divided into five groups according to the year of evaluation (1999-2002, 2003-2006, 2007-2010, 2011-2014 and 2015-2017). The control of CVRFs and the prevalence of prior CVD were evaluated.

RESULTS

We evaluated 360 patients (64.4% men, age 38.9 ± 7.1 years). LDL-cholesterol <100 mg/dl increased from 22.7% to 76.9% (1999-2002 vs. 2015-2017; p < 0.001), as did the use of statins (from 24.7% to 74.5%; p < 0.001). Systolic blood pressure decreased from 138.8 ± 27.6 to 125.1 ± 27.9 mmHg (p = 0.001) and current smokers from 48% to 25% (p = 0.018). Intensive insulin treatment increased from 34.4% to 93.6% (p < 0.001). Diabetes duration before the initiation of renal replacement therapy increased from 23 ± 5.5 to 26.9 ± 8.9 years (p = 0.001). Overall, 30.3% had previous CVD, without significant changes over time (p = 0.699), albeit patients were older and had longer diabetes duration.

CONCLUSIONS

Patients with T1D and ESRD referred for KPTx have better control of CVRFs over time, which might lead to a decrease in cardiovascular events.

Combination of calcineurin and mTOR inhibitors in kidney transplantation: a propensity score analysis based on current clinical practice

INTRODUCTION

The TRANSFORM study demonstrated that an immunosuppression based on a combination of calcineurin inhibitors and de-novo mTOR inhibitors (mTORi) is safe and effective in kidney transplant recipients. However, data that validate this approach in clinical practice are currently missing.

MATERIALS AND METHODS

Analysis of 401 kidney transplant recipients transplanted from June 2013 to December 2016. All patients received tacrolimus with prednisone in combination with either mycophenolate (n = 186) or mTORi (either everolimus or sirolimus, n = 215). A propensity score to receive mTORi was calculated based on the inverse probability of treatment weighting (IPTW) from the following parameters: age and sex of donor and recipient, BMI, previous transplants, diabetes, cPRA, dialysis before transplantation, dialysis vintage, type of donor, ABO-incompatibility, HLA-mismatches, induction and ischemia time. Median follow-up was 2.6 [1.9; 3.7] years.

RESULTS

Cox-regression analysis suggests good results for mTORi versus MPA in terms of 1-year biopsy-proven acute rejection (BPAR, P = 0.063), 1-year graft loss (P = 0.025) and patient survival (P < 0.001). Results observed for BPAR and graft failure were largely attributed to those patients that would have been excluded by the TRANSFORM because of some exclusion criteria (52.9% of the population, P = 0.003 for 1-year BPAR and P = 0.040 for graft loss). In patients who met selection criteria for TRANSFORM, no effect of treatment for BPAR or graft failure was observed, while the beneficial effect on overall survival persisted.

CONCLUSIONS

In a real-life setting, a protocol based on de-novo mTORi with tacrolimus and prednisone could be employed as a standard immunosuppressive regimen and was associated with good outcomes.

High cut-off membrane for in-vivo dialysis of free plasma hemoglobin in a patient with massive hemolysis

Background

The possibility of clearing Cell-free Plasma Hemoglobin (CPH) from human plasma may appear attractive, especially when considering the noxious effects that CPH has on the immune function and the renal damage caused by its filtration. The existence of the so-called High Cut-Off (HCO) filters, possessing pores as big as 60 kDa, could potentially allow the clearance of the αβ dimers (31.3 kDa), the form in which the α2β2 hemoglobin tetramers (62.6 kDa) physiologically dissociate in plasma. We present herein the first reported case in which such an attempt was made.

Case presentation

The patient was a 51-year-old man with hemolytic crisis due to glucose-6-phosphate dehydrogenase deficiency, further complicated by pigment-induced nephropathy. He underwent a 48-h CVVHD session, in which a HCO filter was used. The Sieving Coefficient (SC) for CPH was initially 0.08 and decreased to 0.02 after 24 h. This unexpected low SC was due to the initial high concentration of CPH (4.24 g/L). At such concentrations, the α2β2 tetramer poorly dissociates into the αβ dimer; but increases exponentially at concentrations lower than 1 g/L.

Conclusions

Clearance of CPH through a HCO filter is technically feasible but its performance markedly relies on the initial concentration of CPH. Critically ill patients with smoldering hemolysis, as it happens during septic shock or ECMO treatment, may benefit the most from the use of this membrane in order to clear CPH.