Acute Kidney Disease After Liver and Heart Transplantation

Serum creatinine is an unreliable marker of renal function in patients undergoing heart transplantation

BACKGROUND

Renal dysfunction is a common complication after heart transplantation (Htx). Glomerular filtration rate (GFR) can be assessed by various estimating equations (eGFR). We evaluated the correlation, agreement, and accuracy between eGFR and mGFR and the ability of eGFR to track changes in mGFR early after Htx.

METHODS

A single-center prospective observational study on 55 patients undergoing Htx. Serum creatinine and mGFR (plasma clearance of Cr51-EDTA or iohexol) were measured preoperatively and on the fourth postoperative day. The accuracy of eGFR to predict true mGFR was calculated as the percentage of patients with an eGFR within 30% of mGFR (P30). The agreement between eGFR and mGFR was assessed according to Bland and Altman. A four-quadrant plot was made to evaluate the ability of eGFR to track changes in mGFR.

RESULTS

The accuracy of eGFR to assess mGFR was 52%. The bias was 11.2 ± 17.4 mL/min/1.72 m2. The limits of agreement were -23.0 to 45.4 mL/min/1.72 m2 and the error 58%. The concordance rate between eGFR and mGFR was 72%.

CONCLUSIONS

eGFR underestimated mGFR and the agreement between eGFR and mGFR was low with an unacceptably large between-group error and low accuracy. Furthermore, the ability of eGFR to assess changes in mGFR, postoperatively, was poor. Thus, the use of estimating equations from serum creatinine will not adequately assess renal function early after major heart surgery. To gain adequate information on renal function early after Htx, GFR needs to be measured, not estimated.

Improved waitlist and comparable post-transplant outcomes in simultaneous heart-kidney transplantation under the 2018 heart allocation system

OBJECTIVE

This study aimed to investigate the clinical trends and the impact of the 2018 heart allocation policy change on both waitlist and post-transplant outcomes in simultaneous heart-kidney transplantation in the United States.

METHODS

The United Network for Organ Sharing registry was queried to compare adult patients before and after the allocation policy change. This study included 2 separate analyses evaluating the waitlist and post-transplant outcomes. Multivariable analyses were performed to determine the 2018 allocation system's risk-adjusted hazards for 1-year waitlist and post-transplant mortality.

RESULTS

The initial analysis investigating the waitlist outcomes included 1779 patients listed for simultaneous heart-kidney transplantation. Of these, 1075 patients (60.4%) were listed after the 2018 allocation policy change. After the policy change, the waitlist outcomes significantly improved with a shorter waitlist time, lower likelihood of de-listing, and higher likelihood of transplantation. In the subsequent analysis investigating the post-transplant outcomes, 1130 simultaneous heart-kidney transplant recipients were included, where 738 patients (65.3%) underwent simultaneous heart-kidney transplantation after the policy change. The 90-day, 6-month, and 1-year post-transplant survival and complication rates were comparable before and after the policy change. Multivariable analyses demonstrated that the 2018 allocation system positively impacted risk-adjusted 1-year waitlist mortality (sub-hazard ratio, 0.66, 95% CI, 0.51-0.85, P < .001), but it did not significantly impact risk-adjusted 1-year post-transplant mortality (hazard ratio, 1.03; 95% CI, 0.72-1.47, P = .876).

CONCLUSIONS

This study demonstrates increased rates of simultaneous heart-kidney transplantation with a shorter waitlist time after the 2018 allocation policy change. Furthermore, there were improved waitlist outcomes and comparable early post-transplant survival after simultaneous heart-kidney transplantation under the 2018 allocation system.

Simultaneous Heart-kidney Transplant With Planned Delayed Implantation of the Kidney Graft After Ex Vivo Perfusion

BACKGROUND

Simultaneous heart-kidney transplant (SHK) is an established option for patients with severe heart failure and chronic kidney disease. Recent studies in simultaneous liver-kidney transplantation demonstrate favorable outcomes achieved by delaying implantation of the kidney for over 24 h. This report describes a case series of consecutive patients listed for SHK who had planned delayed implantation of the kidney graft.

METHODS

This case series represents a retrospective analysis of SHK patients extracted from the transplant database at a single center.

RESULTS

There were 7 patients who underwent SHK during the study period. In all cases, kidney grafts were maintained on hypothermic ex vivo pulsatile perfusion for delayed implantation (mean cold ischemia 53 h [range, 31-69]). The first 5 patients had 100% 1-y heart and kidney graft survival with good function. Patient 6 was unstable on extracorporeal membrane oxygenation post-heart transplant. The kidney was implanted at 69 h, and the patient died soon thereafter. Patient 7 was also unstable on extracorporeal membrane oxygenation after heart transplant. The decision was made to implant the kidney into a backup kidney recipient. The heart transplant recipient subsequently died several days later, whereas the kidney was successfully transplanted in the alternate candidate.

CONCLUSIONS

This case series highlights the potential utility of delayed kidney implantation in SHK patients. SHK with delayed renal transplant may provide an improved physiologic environment for renal transplant, which may result in improved early renal graft function. Delayed kidney transplant also provides the opportunity to transplant the kidney graft into an alternate candidate.

Atrial natriuretic peptide in the prevention of acute renal dysfunction after heart transplantation-a randomized placebo-controlled double-blind trial

BACKGROUND

Acute kidney injury (AKI) and renal dysfunction after heart transplantation are common and serious complications. Atrial natriuretic peptide (ANP) has been shown to increase glomerular filtration rate (GFR) and exert renoprotective effects when used for the prevention/treatment of AKI in cardiac surgery. We tested the hypothesis that intraoperative and postoperative administration of ANP could prevent a postoperative decrease in renal function early after heart transplantation.

METHODS

Seventy patients were randomized to receive either ANP (50 ng/kg/min) (n = 33) or placebo (n = 37) starting after induction of anesthesia and continued for 4 days after heart transplantation or until treatment with dialysis was started. The primary end-point of the present study was measured GFR (mGFR) at day 4, assessed by plasma clearance of a renal filtration marker. Also, the incidence of postoperative AKI and dialysis were assessed.

RESULTS

Median (IQR) mGFR at day 4 postoperatively was 60.0 (57.0) and 50.1 (36.3) ml/min/1.72 m2 for the placebo and ANP groups, respectively (p = .705). During ongoing ANP infusion, the need for dialysis was 21.6% and 9.1% for the placebo and ANP groups, respectively (p = .197). The incidences of AKI for the placebo and the ANP groups were 76.5% and 63.6%, respectively (p = .616). The incidences of AKI stage 1 were 32.4% and 21.2% for the placebo and ANP groups, respectively (p = .420) and for AKI stage 2 or 3, 37.8% and 42.4%, respectively (p = .808).

CONCLUSION

The study failed to detect that ANP infusion attenuates renal dysfunction or decreases the incidence of AKI after heart transplantation.

Clinical trends, risk factors, and temporal effects of post-transplant dialysis on outcomes following orthotopic heart transplantation in the 2018 United States heart allocation system

BACKGROUND

This study evaluated the current clinical trends, risk factors, and temporal effects of post-transplant dialysis on outcomes following orthotopic heart transplantation after the 2018 United States adult heart allocation policy change.

METHODS

The United Network for Organ Sharing (UNOS) registry was queried to analyze adult orthotopic heart transplant recipients after the October 18, 2018 heart allocation policy change. The cohort was stratified according to the need for post-transplant de novo dialysis. The primary outcome was survival. Propensity score-matching was performed to compare the outcomes between 2 similar cohorts with and without post-transplant de novo dialysis. The impact of post-transplant dialysis chronicity was evaluated. Multivariable logistic regression was performed to identify risk factors for post-transplant dialysis.

RESULTS

A total of 7,223 patients were included in this study. Out of these, 968 patients (13.4%) developed post-transplant renal failure requiring de novo dialysis. Both 1-year (73.2% vs 94.8%) and 2-year (66.3% vs 90.6%) survival rates were lower in the dialysis cohort (p < 0.001), and the lower survival rates persisted in a propensity-matched comparison. Recipients requiring only temporary post-transplant dialysis had significantly improved 1-year (92.5% vs 71.6%) and 2-year (86.6 % vs 52.2%) survival rates compared to the chronic post-transplant dialysis group (p < 0.001). Multivariable analysis demonstrated low pretransplant estimated glomerular filtration (eGFR) and bridge with extracorporeal membrane oxygenation (ECMO) were strong predictors of post-transplant dialysis.

CONCLUSIONS

This study demonstrates that post-transplant dialysis is associated with significantly increased morbidity and mortality in the new allocation system. Post-transplant survival is affected by the chronicity of post-transplant dialysis. Low pretransplant eGFR and ECMO are strong risk factors for post-transplant dialysis.

Intraoperative risk factors of acute kidney injury after liver transplantation

Acute kidney injury (AKI) is one of the most common complications of liver transplantation (LT). We examined the impact of intraoperative management on risk for AKI following LT. In this retrospective observational study, we linked data from the electronic health record with standardized transplant outcomes. Our primary outcome was stage 2 or 3 AKI as defined by Kidney Disease Improving Global Outcomes guidelines within the first 7 days of LT. We used logistic regression models to test the hypothesis that the addition of intraoperative variables, including inotropic/vasopressor administration, transfusion requirements, and hemodynamic markers improves our ability to predict AKI following LT. We also examined the impact of postoperative AKI on mortality. Of the 598 adult primary LT recipients included in our study, 43% (n = 255) were diagnosed with AKI within the first 7 postoperative days. Several preoperative and intraoperative variables including (1) electrolyte/acid-base balance disorder (International Classification of Diseases, Ninth Revision codes 253.6 or 276.x and International Classification of Diseases, Tenth Revision codes E22.2 or E87.x, where x is any digit; adjusted odds ratio [aOR], 1.917, 95% confidence interval [CI], 1.280-2.869; p = 0.002); (2) preoperative anemia (aOR, 2.612; 95% CI, 1.405-4.854; p = 0.002); (3) low serum albumin (aOR, 0.576; 95% CI, 0.410-0.808; p = 0.001), increased potassium value during reperfusion (aOR, 1.513; 95% CI, 1.103-2.077; p = 0.01), and lactate during reperfusion (aOR, 1.081; 95% CI, 1.003-1.166; p = 0.04) were associated with posttransplant AKI. New dialysis requirement within the first 7 days postoperatively predicted the posttransplant mortality. Our study identified significant association between several potentially modifiable variables with posttransplant AKI. The addition of intraoperative data did not improve overall model discrimination.

Prognostic value of protein biomarkers in liver transplantation: A systematic review

Liver transplantation is currently the preferred method for the treatment of advanced liver disease and early-stage hepatocellular carcinoma (HCC). Although advances in surgical techniques, immunosuppressive drugs and postoperative management have reduced the incidence of postoperative complications, how to effectively predict or diagnose postoperative complications earlier and reduce their incidence is still a clinical concern. We performed a comprehensive proteomics literature research to identified protein biomarkers in complications after liver transplantation. Seventeen studies met the inclusion criteria including ischemia reperfusion injury (IRI) (n = 4), acute rejection (AR) (n = 4), renal dysfunction (n = 4), HCC recurrence (n = 2), primary graft dysfunction (PGD) (n = 1), infection (n = 1), and liver fibrosis (n = 1). A total of 625 differentially expressed proteins (DEPs) have been reported between postoperative complications and controls, of which 63 have been validated by quantitative protein expression and 26 have been reported by at least two studies and showed consistently changes. The results of the bioinformation analysis show that the immune system, especially the innate immune system and cytokine signaling in immune system, is an important protein-mediated pathway that affects the prognosis of liver transplantation.

Risk of Renal Dysfunction Following Heart Transplantation in Patients Bridged with a Left Ventricular Assist Device

Acute renal failure (ARF) and chronic kidney disease (CKD) are associated with short- and long-term morbidity and mortality following heart transplantation (HT). We investigated the incidence and risk factors for developing ARF requiring hemodialysis (HD) and CKD following HT specifically in patients with a left ventricular assist device (LVAD). We examined the International Society for Heart and Lung Transplantation (ISHLT) Thoracic Transplant Registry for heart transplant patients between January 2000 and June 2015. We compared patients bridged with durable continuous-flow LVAD to those without LVAD support. Primary outcomes were ARF requiring HD before discharge following HT and CKD (defined as creatinine >2.5 mg/dl, permanent dialysis, or renal transplant) within 3 years. There were 18,738 patients, with 4,535 (24%) bridged with LVAD support. Left ventricular assist device patients had higher incidence of ARF requiring HD and CKD at 1 year, but no significant difference in CKD at 3 years compared to non-LVAD patients. Among LVAD patients, body mass index (BMI) (odds ratio [OR] = 1.79, p < 0.001), baseline estimated glomerular filtration rate (eGFR) (OR = 0.43, p < 0.001), and ischemic time (OR = 1.28, p = 0.014) were significantly associated with ARF requiring HD. Similarly, BMI (hazard ratio [HR] = 1.49, p < 0.001), baseline eGFR (HR = 0.41, p < 0.001), pre-HT diabetes mellitus (DM) (HR = 1.37, p = 0.011), and post-HT dialysis before discharge (HR = 3.93, p < 0.001) were significantly associated with CKD. Left ventricular assist device patients have a higher incidence of ARF requiring HD and CKD at 1 year after HT compared with non-LVAD patients, but incidence of CKD is similar by 3 years. Baseline renal function, BMI, ischemic time, and DM can help identify LVAD patients at risk of ARF requiring HD or CKD following HT.

Risk factors of renal replacement therapy after heart transplantation: a retrospective single-center study

BACKGROUND

Acute kidney injury (AKI) and renal replacement therapy (RRT) are common after heart transplantation (HT). The need for RRT has been reported to be one of the most important predictors of a poor prognosis after HT. Therefore, it is important to early identify risk factors of RRT after HT. However, in the heart transplantation setting, the risk factors are less well studied, and some of the conclusions are controversial. This study aimed to identify the clinical predictors of RRT after HT.

METHODS

This single-center, retrospective study from January 2010 to June 2021 analyzed risk factors (pre-, intra-, and postoperative characteristics) of 163 patients who underwent HT. The endpoint of the study was RRT within 7 days of HT. Risk factors were analyzed by multivariable logistic regression models.

RESULTS

Fifty-five (33.74%) recipients required RRT within 7 days of HT. Factors independently associated with RRT after HT were as follows: a baseline estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m² [odds ratio (OR) =3.123; 95% confidence interval (CI): 1.183-8.244; P=0.022], a dose of intraoperative methylprednisolone >10 mg/kg (OR =3.197; 95% CI: 1.290-7.923; P=0.012), the use of mechanical circulatory support (MCS) during surgery (OR =4.903; 95% CI: 1.628-14.766; P=0.005), a cardiopulmonary bypass (CPB) time ≥5 hours (OR =3.929; 95% CI: 1.222-12.634; P=0.022), and postoperative serum total bilirubin (TBIL) ≥60 umol/L (OR =5.105; 95% CI: 1.868-13.952; P=0.001). Protective factors were higher postoperative serum albumin (OR =0.907; 95% CI: 0.837-0.983; P=0.017) and higher postoperative left ventricular ejection fraction (LVEF) (OR =0.908; 95% CI: 0.838-0.985; P=0.020).

CONCLUSIONS

A low preoperative eGFR, a high intraoperative dose of methylprednisolone, a long CPB time, the use of mechanical circulatory support, and a high postoperative TBIL were risk factors for RRT after HT. While a high postoperative serum albumin level and a high left ventricular ejection fraction were protective factors. Understanding these risk factors may help us identify high-risk patients and intervene early.

CKD in Recipients of Nonkidney Solid Organ Transplants: A Review

Chronic kidney disease (CKD) after solid organ transplant is a common clinical presentation, affecting 10% to 20% of liver, heart and lung transplant recipients and accounting for approximately 5% of the kidney transplant waiting list. The causes of CKD are different for different types of transplants and are not all, or even predominantly, due to calcineurin inhibitor toxicity, with significant heterogeneity particularly in liver transplant recipients. Many solid organ transplant recipients with advanced CKD benefit from kidney transplantation, but have a higher rate of death while waitlisted and higher mortality following transplant than the general kidney failure population. Recent organ allocation policies and proposals have attempted to address the appropriate identification and prioritization of candidates in need of a kidney transplant, either simultaneous with or following non-kidney transplant. Future research should focus on predictive factors for individuals identified at high risk for progression to kidney failure and death, and strategies to preserve kidney function and minimize the CKD burden in this unique patient population.

Incidence and long-term outcome of heart transplantation patients who develop postoperative renal failure requiring dialysis

BACKGROUND

Acute renal failure requiring dialysis after heart transplantation remains a significant clinical issue because of its increasing incidence. We aimed to investigate its time trends, clinical predictors, and long-term outcomes.

METHODS

Adult heart transplantation recipients registered in the United Network for Organ Sharing registry between 2009 and 2020 were identified. The patients were grouped according to the requirement for dialysis in the postoperative heart transplantation period. The independent risk predictors were identified, and the association between post-heart transplantation renal failure requiring dialysis and long-term mortality accounting for re-transplantation was investigated.

RESULTS

A total of 28,170 patients were included in the study, of which 3,371 (12%) required dialysis immediately post-heart transplantation. The incidence increased from 7.9% to 13.9% during the study period. Longer ischemic time, serum creatinine at transplantation >1.2 mg/dL, prior cardiac surgery, higher recipient body mass index, support of mechanical ventilation or extracorporeal membrane oxygenation, and history of congenital heart disease or restrictive/hypertrophic cardiomyopathy were its predictors (all p < 0.05). Patients on posttransplant dialysis had a higher risk of all-cause mortality (adjusted hazard ratio [aHR]: 5.2, 95% CI: 4.7-5.7, p < 0.001), 30 day mortality (aHR: 7.7, 95% CI: 6.3-9.6, p < 0.001) and 1 year mortality (aHR: 7.5, 95% CI: 6.6-8.6, p < 0.001). Post-transplant dialysis was associated with a risk of treated rejection at 1 year.

CONCLUSION

Acute renal failure requiring dialysis after heart transplantation is associated with significantly worse 30 day and long-term mortalities, and thus, early identification of high-risk patients is crucial to prevent severe renal complications.

Impact of diabetes and chronic dialysis on post-transplant survival in combined heart-kidney transplant recipients

Growing research supports an increased survival benefit of combined heart and kidney transplantation in patients with both heart and renal failure. As a result, the frequency of these combined transplants continues to increase. Despite this trend, little has been done to quantify the impact of chronic illness in this population. We identified adult recipients of combined heart-kidney transplant from the Scientific Registry of Transplant Recipients (SRTR) database between 2005 and 2018. We focused on renal disease secondary to diabetes and duration of dialysis as markers of chronic illness. The primary outcome was post-transplant mortality. Our final multivariable Cox proportional hazard model found that diabetes-associated renal disease (HR 1.57, 95% CI 1.14-2.15, p = .01) and dialysis duration (HR 1.08, 95% CI 1.01-1.15, p = .02) were significant predictors of post-transplant mortality. Given the significant impact of dialysis duration and renal disease secondary to diabetes mellitus, these chronically ill patients should be closely examined for conditions such as peripheral vascular disease and frailty, which have been shown to affect mortality in heart transplant recipients and are prevalent in the chronic dialysis population.

Acute kidney injury in renal transplant recipients undergoing cardiac surgery

BACKGROUND

Acute kidney injury (AKI) is a key risk factor for chronic kidney disease in the general population, but has not been investigated in detail among renal transplant recipients (RTRs). We investigated the incidence, severity and risk factors for AKI following cardiac surgery among RTRs compared with non-RTRs with otherwise similar clinical characteristics.

METHODS

We conducted a retrospective cohort study of RTRs (n = 83) and non-RTRs (n = 83) who underwent cardiac surgery at two major academic medical centers. Non-RTRs were matched 1:1 to RTRs by age, preoperative (preop) estimated glomerular filtration rate and type of cardiac surgery. We defined AKI according to Kidney Disease: Improving Global Outcomes criteria.

RESULTS

RTRs had a higher rate of AKI following cardiac surgery compared with non-RTRs [46% versus 28%; adjusted odds ratio 2.77 (95% confidence interval 1.36-5.64)]. Among RTRs, deceased donor (DD) versus living donor (LD) status, as well as higher versus lower preop calcineurin inhibitor (CNI) trough levels, were associated with higher rates of AKI (57% versus 33% among DD-RTRs versus LD-RTRs; P = 0.047; 73% versus 36% among RTRs with higher versus lower CNI trough levels, P = 0.02). The combination of both risk factors (DD status and higher CNI trough level) had an additive effect (88% AKI incidence among patients with both risk factors versus 25% incidence among RTRs with neither risk factor, P = 0.004).

CONCLUSIONS

RTRs have a higher risk of AKI following cardiac surgery compared with non-RTRs with otherwise similar characteristics. Among RTRs, DD-RTRs and those with higher preop CNI trough levels are at the highest risk.

Long-Term Outcomes and Risk Factors of Renal Failure Requiring Dialysis after Heart Transplantation: A Nationwide Cohort Study

Acute kidney injury and renal failure are common after heart transplantation. We retrospectively reviewed a national cohort and identified 1129 heart transplant patients. Patients receiving renal replacement therapy after heart transplantation were grouped into the dialysis cohort. The long-term survival and risk factors of dialysis were investigated. Patients who had undergone dialysis were stratified to early or late dialysis for subgroup analysis. The mean follow-up was five years, the incidence of dialysis was 28.4% (21% early dialysis and 7.4% late dialysis). The dialysis cohort had higher overall mortality compared with the non-dialysis cohort. The hazard ratios of mortality in patients with dialysis were 3.44 (95% confidence interval (CI), 2.73–4.33) for all dialysis patients, 3.58 (95% CI, 2.74–4.67) for early dialysis patients, and 3.27 (95% CI, 2.44–4.36; all p < 0.001) for late dialysis patients. Patients with diabetes mellitus, chronic kidney disease, acute kidney injury, and coronary artery disease were at higher risk of renal failure requiring dialysis. Cardiomyopathy, hepatitis B virus infection, and hyperlipidemia treated with statins were associated with a lower risk of renal dysfunction requiring early dialysis. The use of Sirolimus and Mycophenolate mofetil was associated with a lower incidence of late dialysis. Renal dysfunction requiring dialysis after heart transplantation is common in Taiwan. Early and late dialysis were both associated with an increased risk of mortality in heart transplant recipients.

Effect of cumulative fluid balance on acute kidney injury and patient outcomes after orthotopic liver transplantation: A retrospective cohort study

AIM

Acute kidney injury (AKI) is a serious complication following orthotopic liver transplantation (OLT) and it affects long-term patient survival. The aims of this study were to identify the effects of cumulative fluid balance (FB) on early post-OLT AKI and adverse outcomes and to construct a model to predict AKI.

METHODS

We retrospectively analysed 146 adult patients who underwent OLT. AKI severity was classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Univariate and multivariate logistic regression analyses were used to evaluate the association between cumulative FB and post-OLT AKI. The Kaplan-Meier method was used to estimate the survival rate.

RESULTS

Within the perioperative period of 72 hours, 50% (66/132) of patients developed AKI, with 36 (54%), 16 (24%) and 14 (21%) patients having AKI stages 1, 2 and 3, respectively. The cumulative FB was the risk factors for post-OLT AKI (odds ratio [OR], 1.011; 95% confidence interval [CI], 1.156~6.001; P = .021). Preoperative albumin was a protective factor for post-OLT AKI (OR, 0.309; 95% CI, 0.140~0.731; P = .007). The AKI group requires renal replacement therapy (RRT) more (15.2% vs 0%, P = .001) and associated with postoperative complications (56% vs 28.8%, P = .003). The complication-free survival was lower in the AKI group ([11.90 vs 18.74] months, χ² = 9.60, P = .002).

CONCLUSION

Cumulative FB within 72 hours is associated with post-OLT AKI and requires RRT. Cumulative FB impacts the long-term complication-free survival of the recipients.

Incidence and Impact of Acute Kidney Injury after Liver Transplantation: A Meta-Analysis

Background: The study’s aim was to summarize the incidence and impacts of post-liver transplant (LTx) acute kidney injury (AKI) on outcomes after LTx. Methods: A literature search was performed using the MEDLINE, EMBASE and Cochrane Databases from inception until December 2018 to identify studies assessing the incidence of AKI (using a standard AKI definition) in adult patients undergoing LTx. Effect estimates from the individual studies were derived and consolidated utilizing random-effect, the generic inverse variance approach of DerSimonian and Laird. The protocol for this systematic review is registered with PROSPERO (no. CRD42018100664). Results: Thirty-eight cohort studies, with a total of 13,422 LTx patients, were enrolled. Overall, the pooled estimated incidence rates of post-LTx AKI and severe AKI requiring renal replacement therapy (RRT) were 40.7% (95% CI: 35.4%–46.2%) and 7.7% (95% CI: 5.1%–11.4%), respectively. Meta-regression showed that the year of study did not significantly affect the incidence of post-LTx AKI (p = 0.81). The pooled estimated in-hospital or 30-day mortality, and 1-year mortality rates of patients with post-LTx AKI were 16.5% (95% CI: 10.8%–24.3%) and 31.1% (95% CI: 22.4%–41.5%), respectively. Post-LTx AKI and severe AKI requiring RRT were associated with significantly higher mortality with pooled ORs of 2.96 (95% CI: 2.32–3.77) and 8.15 (95%CI: 4.52–14.69), respectively. Compared to those without post-LTx AKI, recipients with post-LTx AKI had significantly increased risk of liver graft failure and chronic kidney disease with pooled ORs of 3.76 (95% CI: 1.56–9.03) and 2.35 (95% CI: 1.53–3.61), respectively. Conclusion: The overall estimated incidence rates of post-LTx AKI and severe AKI requiring RRT are 40.8% and 7.0%, respectively. There are significant associations of post-LTx AKI with increased mortality and graft failure after transplantation. Furthermore, the incidence of post-LTx AKI has remained stable over the ten years of the study.

Predictors of renal replacement therapy after heart transplantation and its impact on long-term survival

BACKGROUND

Renal replacement therapy (RRT) after heart transplant (HT) is associated with worse prognosis. We aimed to identify predictors of RRT and the impact of this complication on long-term survival.

METHODS

Cohort study of HT patients. Univariate and multivariate competing-risk regression was performed to identify independent predictors of RRT. The cumulative incidence function was plotted for RRT. The Kaplan-Meier method was used to compare long-term survival.

RESULTS

We included 103 patients. At multivariate analysis, only the emergency status of HT (short-term mechanical circulatory support as a bridge to transplant), chronic kidney disease, and low oxygen delivery were independent predictors of RRT (subhazard ratio [SHR] 4.11, 95% CI 1.84-9.14; SHR 3.17, 95% CI 1.29-7.77; SHR 2.86, 95% CI 1.14-7.19, respectively). Elective HT patients that required RRT showed a significantly reduced survival comparable to patients with emergency HT and RRT (75% ± 13% vs. 67% ± 16%). The absence of RRT implied an excellent survival in patients with an emergency status of HT and elective HT (100% vs. 93% ± 4%).

CONCLUSION

The emergency status of HT, chronic kidney disease, and low oxygen delivery were independent predictors of RRT. The occurrence of RRT increases the risk of death in elective HT as much as in patients with an emergency status.

Case Report: First Reported Combined Heart-Liver Transplant in a Patient With a Congenital Solitary Kidney

We report a case of successful combined heart liver transplant in a patient with a congenital solitary kidney. The patient had normal renal function before combined heart-liver transplantation and developed acute kidney injury requiring slow continuous dialysis and subsequent intermittent dialysis for almost 8 weeks post transplantation. Her renal function recovered and she remains off dialysis now 7 months post transplantation. She only currently has mild chronic renal insufficiency. We believe this is the first reported case of successful heart liver transplant in a patient with a congenital solitary kidney.

Unusual Pathology in a Kidney from a Heart-Transplant Patient

Acute kidney injury (AKI) is often observed after heart transplantation. In this setting, acute tubular necrosis is the main histological finding on kidneys. We report the unusual pathology found in a kidney from a heart-transplant patient. The patient experienced several hemodynamic insults, massive transfusion, and implantation of a mechanical circulatory-support device before heart transplantation: there was prolonged AKI after transplantation. A kidney biopsy revealed acute tubular necrosis and renal hemosiderosis, which was probably related to the transfusion and to mechanical circulatory-support device-induced intravascular hemolysis. Assessment of iron during resuscitation could have prevented, at least partly, AKI.

Negative Cardiovascular Consequences of Small Molecule Immunosuppressants

Immunosuppressants are critical after transplantation and prescribed as immune-modulators for autoimmune disorders and glomerulonephritides. Immunosuppressants include large (e.g., thymoglobulin, alemtuzumab, and rituximab) and small molecules (e.g., corticosteroids, calcineurin inhibitors, antimetabolites, and mammalian target of rapamycin (mTOR) inhibitors). The majority of the small molecules worsen traditional cardiovascular risks. This review describes cardiovascular risks of small molecule immunosuppressants: corticosteroids, calcineurin inhibitors (tacrolimus and cyclosporine), and mTOR inhibitors (rapamycin), by categorizing these risks into two categories: ischemic heart disease and nonischemic cardiac effects.

Impact of preoperative chronic renal failure on liver transplantation: a population-based cohort study

Purpose

The purpose of this study was to assess whether preoperative chronic renal failure (CRF) affects the rates of postoperative complications and survival after liver transplantation.

Methods

This population-based retrospective cohort study included 2,931 recipients of liver transplantation performed between 1998 and 2012, enrolled from the Taiwan National Health Insurance Research Database. Patients were divided into two groups, based on the presence or absence of preoperative CRF.

Results

The overall estimated survival rate of liver transplantation recipients (LTRs) with preoperative CRF was significantly lower than that of patients without preoperative CRF (P=0.0085). There was no significant difference between the groups in terms of duration of intensive care unit stay, total hospital stay, bacteremia, postoperative bleeding, and pneumonia during hospitalization. Long-term adverse effects, including cerebrovascular disease and coronary heart disease, were not different between patients with versus without CRF.

Conclusion

These findings suggest that LTRs with preoperative CRF have a higher rate of mortality.

Postoperative Delirium After Liver Transplantation is Associated With Increased Length of Stay and Lower Survival in a Prospective Cohort

Introduction:

Although postoperative delirium (POD) is a common in-hospital complication associated with negative outcomes, evidence in liver transplantation (LT) is scarce.

Objective:

We examined the incidence and duration of POD, its impact on outcomes and health-care utilization, and described predisposing and precipitating factors favoring POD development.

Design:

This prospective cohort study included adults undergoing transplantation in a tertiary hospital. Postoperative delirium was assessed 3 times daily until 24 days post-LT, with the Intensive Care Delirium Screening Checklist on the intensive care unit (ICU) and the Delirium Observation Screening Scale on the ward. Postoperative delirium was noted if any of the daily measurements was positive.

Results:

Forty-two patients (69% male, mean age 55 years, median Model for End-Stage Liver Disease score 15 [interquartile range 8-26]) were included. The incidence of POD was 45.2%, with a median duration of 5 days. Patients with POD had longer ICU (median 8 vs 2 days, P = .000) and hospital stays (median 32 vs 14 days, P = .000) as well as shorter survival (Breslow test P = .045, log-rank test P = .150). Pre-LT comorbidities and perioperative factors might be related to POD development.

Conclusion:

Nurses are key persons in the detection of POD in the daily clinical routine. The high incidence of POD and its negative association with patient outcomes highlight not only the relevance of systematic assessment of POD after LT but also the need for preventive interventions.