Donor-recipient Size Mismatch Research Articles

#2040 Effect of donor–recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study

Abstract Background and Aims Kidney transplantation (KT) is the main treatment option for patients with end-stage kidney disease (ESKD). However, it is limited by the low number of donor organs. Moreover, donor–recipient size mismatching is a common problem in KT given the various types of donors. Donor–recipient size mismatching is commonly occurs in pediatric kidney transplantation (KT). However, its effect on graft survival remains unknown. This study aimed to determine the effect of donor–recipient size mismatch on the long-term survival rate of transplant kidneys in pediatric KT. Method A total of 241 pediatric patients who received KT were enrolled. The medical records of all patients were retrospectively reviewed, and the correlation between donor–recipient size mismatch and graft function and long-term graft outcome was analyzed according to donor–recipient size mismatch. Results Recipients and donors’ mean body weight at the time of KT were 34.31 ± 16.85 and 56.53 ± 16.73 kg, respectively. The mean follow-up duration was 96.49 ± 52.98 months. The mean age of donors was 34.74 ± 14.91 years, and the ratio of males and females was 105:136. Approximately 81.7%, 1.2%, and 17.0% of all transplant donors were identified as living-related, living-unrelated, and deceased donors, respectively. A significant positive correlation was observed between donor–recipient body weight ratio (DRBWR) or donor–recipient body surface area ratio (DRBSR) and graft function until 1 year after KT. However, this correlation could not be confirmed at the last follow-up. The results of long-term survival analysis using Fine and Gray's subdistribution hazard model showed no significant difference of the survival rate of the transplant kidney according to DRBWR or DRBSR. Conclusion Donor–recipient size mismatch in pediatric KT is not an important factor in determining the long-term prognosis of transplant kidneys.

Effect of donor-recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study.

Donor-recipient size mismatching is commonly occurs in pediatric kidney transplantation (KT). However, its effect on graft survival remains unknown. This study aimed to determine the effect of donor-recipient size mismatch on the long-term survival rate of transplant kidneys in pediatric KT. A total of 241 pediatric patients who received KT were enrolled. The medical records of all patients were retrospectively reviewed, and the correlation between donor-recipient size mismatch and graft function and long-term graft outcome was analyzed according to donor-recipient size mismatch. Recipients and donors' mean body weight at the time of KT were 34.31 ± 16.85 and 56.53 ± 16.73 kg, respectively. The mean follow-up duration was 96.49 ± 52.98 months. A significant positive correlation was observed between donor-recipient body weight ratio (DRBWR) or donor-recipient body surface area ratio (DRBSR) and graft function until 1 year after KT. However, this correlation could not be confirmed at the last follow-up. The results of long-term survival analysis using Fine and Gray's subdistribution hazard model showed no significant difference of the survival rate of the transplant kidney according to DRBWR or DRBSR. Donor-recipient size mismatch in pediatric KT is not an important factor in determining the long-term prognosis of transplant kidneys.

Role of intelligent/interactive qualitative and quantitative analysis-three-dimensional estimated model in donor-recipient size mismatch following deceased donor liver transplantation.

Donor-recipient size mismatch (DRSM) is considered a crucial factor for poor outcomes in liver transplantation (LT) because of complications, such as massive intraoperative blood loss (IBL) and early allograft dysfunction (EAD). Liver volumetry is performed routinely in living donor LT, but rarely in deceased donor LT (DDLT), which amplifies the adverse effects of DRSM in DDLT. Due to the various shortcomings of traditional manual liver volumetry and formula methods, a feasible model based on intelligent/interactive qualitative and quantitative analysis-three-dimensional (IQQA-3D) for estimating the degree of DRSM is needed. To identify benefits of IQQA-3D liver volumetry in DDLT and establish an estimation model to guide perioperative management. We retrospectively determined the accuracy of IQQA-3D liver volumetry for standard total liver volume (TLV) (sTLV) and established an estimation TLV (eTLV) index (eTLVi) model. Receiver operating characteristic (ROC) curves were drawn to detect the optimal cut-off values for predicting massive IBL and EAD in DDLT using donor sTLV to recipient sTLV (called sTLVi). The factors influencing the occurrence of massive IBL and EAD were explored through logistic regression analysis. Finally, the eTLVi model was compared with the sTLVi model through the ROC curve for verification. A total of 133 patients were included in the analysis. The Changzheng formula was accurate for calculating donor sTLV (P = 0.083) but not for recipient sTLV (P = 0.036). Recipient eTLV calculated using IQQA-3D highly matched with recipient sTLV (P = 0.221). Alcoholic liver disease, gastrointestinal bleeding, and sTLVi > 1.24 were independent risk factors for massive IBL, and drug-induced liver failure was an independent protective factor for massive IBL. Male donor-female recipient combination, model for end-stage liver disease score, sTLVi ≤ 0.85, and sTLVi ≥ 1.32 were independent risk factors for EAD, and viral hepatitis was an independent protective factor for EAD. The overall survival of patients in the 0.85 < sTLVi < 1.32 group was better compared to the sTLVi ≤ 0.85 group and sTLVi ≥ 1.32 group (P < 0.001). There was no statistically significant difference in the area under the curve of the sTLVi model and IQQA-3D eTLVi model in the detection of massive IBL and EAD (all P > 0.05). IQQA-3D eTLVi model has high accuracy in predicting massive IBL and EAD in DDLT. We should follow the guidance of the IQQA-3D eTLVi model in perioperative management.

Effect of donor-recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study

Effect of donor-recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study

Pediatric Transplant Interventions

The field of pediatric organ transplantation has grown significantly in recent decades, with interventional radiology (IR) playing an essential role in managing pre- and post-transplant complications. Pediatric transplant patients face unique challenges compared to adults, including donor-recipient size mismatch, and complications of a growing child with changing physiology. Interventional radiologists play a major role in pediatric renal and liver transplant. IR interventions begin early in the child's pre-transplant journey, with diagnostic procedures such as biopsies, angiograms, and cholangiograms. These procedures are essential for understanding the etiology of organ failure and identifying potential transplant candidates. Minimally invasive therapeutic procedures may serve as bridges to transplant and may include vascular access optimization for hemodialysis, TIPS shunt creation, and tumor embolization or ablation. After transplant, image-guided biopsies for the surveillance of graft rejection and treatment of vascular or luminal stenoses, pseudoaneurysms, and anastomotic leaks can maintain the function and longevity of the transplant organ. Careful consideration must be given to patient size and evolving anatomy, radiation exposure, and the need for deeper sedation for pediatric patients. Despite these challenges, the integration of IR in pediatric transplant care has proven beneficial, offering minimally invasive alternatives to surgery, faster recovery times, and improved outcomes.

Assessing Donor-Recipient Size Mismatch in Pediatric Heart Transplantation: Lessons Learned From Over 7,500 Transplants

BackgroundTo date, no studies have identified an optimal metric to match donor-recipient (D-R) pairs in pediatric heart transplantation (HT). ObjectivesThis study sought to identify size mismatch metrics that predicted graft survival post-HT. MethodsD-R pairs undergoing HT in Pediatric Heart Transplant Society database from 1993 to 2021 were included. Effects of size mismatch by height, weight, body mass index, body surface area, predicted heart mass, and total cardiac volume (TCV) on 1- and 5-year graft survival and morbidity outcomes (rejection and cardiac allograft vasculopathy) were evaluated. Cox models with stepwise selection identified size metrics that independently predicted graft survival. ResultsOf 7,715 D-R pairs, 36.0% were well matched (D-R ratio: −20% to +20%) by weight, 39.0% by predicted heart mass, 50.0% by body surface area, 57.0% by body mass index, 71.0% by height, and 93.0% by TCV. Of all size metrics, only D-R mismatch by height and TCV predicted graft survival at 1 and 5 years. Effects of D-R size mismatch on graft survival were nonlinear. At both 1 and 5 years post-HT, D-R undersizing and oversizing by height led to increased graft loss, with graft loss observed more frequently with undersizing. Moderately undersized donors by height (D-R ratio: <−30%) frequently experienced rejection post-HT (P < 0.001). Assessing D-R size matching by TCV, minimal donor undersizing was protective, while oversizing up to 25% was not associated with increased graft loss. ConclusionsIn pediatric HT, D-R appear most optimally matched using TCV. Only D-R size mismatch by TCV and height independently predicts graft survival. Standardizing size matching across centers may reduce donor discard.

Size-mismatched transplantation from large donors to small recipients is associated with pancreas graft thrombosis: A retrospective national observational study.

Donor-recipient (D/R) size mismatch has been evaluated for a number of organs but not for pancreas transplantation. We retrospectively evaluated 438 patients who had undergone pancreas transplantation. The D/R body surface area (BSA) ratio was calculated, and the relationship between the ratio and graft prognosis was evaluated. We divided the patients into two groups and evaluated graft survival. The incidence of pancreas graft thrombosis resulting in graft failure within 14days and 1-year graft survival were compared using Kaplan-Meier curves, and the prognostic factors associated with graft thrombosis were identified by univariate and multivariate analyses. The mean/median donor and recipient BSAs were 1.63m2 /1.65m2 , and 1.57m2 /1.55m2 , respectively; the mean and median D/R BSAs were both 1.05. The receiver operating characteristic curve cutoff for the D/R BSA ratio was 1.09, and significant differences were identified between patients with ratios of ≥1.09 (high group) versus <1.09 (low group). The incidence of graft thrombosis resulting in pancreas graft failure within 14days was significantly higher in the high group than in the low group (p<.01). One-year overall and death-censored pancreas graft survival were significantly higher in the low group than in the high group (p<.01). Multivariate analysis identified recipient height, donor BSA, and donor hemoglobin A1c as significant independent factors for graft thrombosis. Cubic spline curve analysis indicated an increased risk of graft thrombosis with increasing D/R BSA ratio. D/R size mismatch is associated with graft thrombosis after pancreas transplantation.

Living donor liver transplant: A strategy to increase transplant access

Living donor liver transplant: A strategy to increase transplant access

Pediatric renal transplantation-A UNOS database analysis of donor-recipient size mismatch.

We used the BSAi (Donor BSA/Recipient BSA) to assess whether transplanting a small or large kidney into a pediatric recipient relative to his/her size influences renal transplant outcomes. We included 14 322 single-kidney transplants in pediatric recipients (0-17 years old) (01/2000-02/2020) from the United Network for Organ Sharing database. We divided cases into four BSAi groups (BSAi ≤ 1, 1 < BSAi ≤ 2, 2 < BSAi ≤ 3, BSAi > 3). There were no differences concerning delayed graft function (DGF) or primary non-function (PNF) rates, whether the grafts were from living or brain-dead donors. In both transplants coming from living donors and brain-dead donors, cases with BSAi > 3 and cases with 2 < BSAi ≤ 3 had similar graft survival (p=.13 for transplants from living donors, p=.413 for transplants from brain-dead donors), and both groups had longer graft survival than cases with 1 < BSAi ≤ 2 and cases with BSAi ≤ 1 (p < .001). The difference in 10-year graft survival rates between cases with BSAi > 3 and cases with BSAi ≤ 1 reached around 25% in both donor types. The better graft survival in transplants with BSAi > 2 was confirmed in multivariable analysis. There is no significant impact of donor-recipient size mismatch on DGF and PNF rates in pediatric renal transplants. However, graft survival is significantly improved when the donor's size is more than twice the pediatric recipient's size.

Influence of Body Mass Index in Donor-Recipient Size Mismatch in Pediatric Heart Transplantation.

Body weight is the traditional metric for matching donor and recipient size for pediatric heart transplantation (pHT). We hypothesized that mismatch in body mass index (BMI) or body surface area (BSA) rather than weight is better associated with outcomes of transplantation and therefore should be used for donor-recipient size matching. Analysis of the United Network for Organ Sharing database limited to pHT recipients was performed. Donor and recipient mismatch groups were created for weight, BMI, and BSA ratios. Differences in recipient characteristics between each cohort and the impact of mismatch on outcomes were statistically analyzed. A total of 4,465 patients were included in the analysis of which 43% had congenital heart disease (CHD). There were significant differences in patient characteristics by matching, independent of the matching parameter. Multivariable regression analysis showed that a low donor-recipient BMI ratio (compared to normal) (CHD OR 1.70; non-CHD 2.78) was a predictor of one-year mortality (all P < .001) in both CHD and non-CHD cohorts. Low BMI ratio was also associated with worse long-term survival in non-CHD groups, but not in the CHD cohort. Weight and BSA ratio did not predict one year or long-term survival. The use of low BMI donors compared to recipient may predict poor early and long-term survival and therefore should be avoided in pHT. The use of BMI matching may improve donor-recipient matching in pHT.

Donor-Recipient Body Surface Area Mismatch and the Outcome of Liver Transplantation in the UK.

Introduction: Too small or too big liver grafts for recipient's size has detrimental effects on transplant outcomes. Research Questions: The purpose was to correlate donor-recipient body surface area ratio or body surface area index with recipient survival, graft survival, hepatic artery or portal vein, or vena cava thrombosis. High and low body surface area index cut-off points were determined. Design: There were 11,245 adult recipients of first deceased donor whole liver-only grafts performed in the UK from January 2000 until June 2020. The transplants were grouped according to the body surface area index and compared to complications, graft and recipient survival. Results: The body surface area index ranged from 0.491 to 1.691 with a median of 0.988. The body surface area index > 1.3 was associated with a higher rate of portal vein thrombosis within the first 3 months (5.5%). This risk was higher than size-matched transplants (OR: 2.878, 95% CI: 1.292-6.409, P = 0.01). Overall graft survival was worse in transplants with body surface area index ≤ 0.85 (HR: 1.254, 95% CI: 1.051-1.497, P = 0.012) or body surface area index > 1.4 (HR: 3.704, 95% CI: 2.029-6.762, P < 0.001) than those with intermediate values. The graft survival rates were reduced by 2% for cases with body surface area index ≤ 0.85 but were decreased by 20% for cases with body surface area index > 1.4. These findings were confirmed by bootstrap internal validation. No statistically significant differences were detected for hepatic artery thrombosis, occlusion of hepatic veins/inferior vena cava or recipient survival. Conclusions: Donor-recipient size mismatch affects the rates of portal vein thrombosis within the first 3 months and overall graft survival in deceased-donor liver transplants.

Prediction of early graft function after living donor kidney transplantation by quantifying the "nephron mass" using CT-volumetric software.

Early renal function after living-donor kidney transplantation (LDKT) depends on the "nephron mass" in the renal graft. In this study, as a possible donor-recipient size mismatch parameter that directly reflects the "nephron mass," the cortex to recipient weight ratio (CRWR) was calculated by CT-volumetric software, and its ability to predict early graft function was examined. One hundred patients who underwent LDKT were enrolled. Patients were classified into a developmental cohort (n = 79) and a validation cohort (n = 21). Using the developmental cohort, the correlation coefficients between size mismatch parameters, including CRWR, and the posttransplantation estimated glomerular filtration rate (eGFR) were calculated. Multiple regression analysis was conducted to define a formula to predict eGFR 1-month posttransplantation. Using the validation cohort, the validity of the formula was examined. The correlation coefficient was the highest for CRWR (1-month r = 0.66, p < 0.001). By multiple regression analysis, eGFR at 1-month was predicted using the linear model: 0.23 × donor preoperative eGFR + 17.03 × CRWR + 8.96 × preemptive transplantation + 5.10 (adjusted coefficient of determination = 0.54). In most patients in the validation cohort, the observed eGFR was within a 10 ml/min/1.73 m2 margin of the predicted eGFR. CRWR was the strongest parameter to predict early graft function. Predicting renal function using this formula could be useful in clinical application to select proper donors and to avoid unnecessary postoperative medical interventions.

REPLY: Reply to Kumar and colleagues.

The author reported no conflicts of interest.The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.In their recent letter to the Editor, Kumar and colleagues1Kumar N. Flores A.S. Hussain N. Ganapathi A.M. Whitson B.A. Essandoh M.K. et al.Ensuring pulmonary artery patency in donor-recipient size mismatch: a collaborative challenge.J Thorac Cardiovasc Surg Tech. 2022; 15: 206-207Scopus (4) Google Scholar provided an important suggestion for additional evaluation of the pulmonary artery anastomosis after lung transplantation with transesophageal echocardiography (TEE) in the operating room. We thank Yokoyama and colleagues2Yokoyama Y. Chen-Yoshikawa T.F. Nakajima D. Ohsumi A. Date H. Various techniques for anastomosis of pulmonary arteries with size mismatch during lung transplantation.J Thorac Cardiovasc Surg Tech. 2021; 9: 192-194Scopus (7) Google Scholar for their previous article on anastomotic techniques that again highlight the importance of a technically optimal operation, which includes an unobstructed pulmonary artery anastomosis. The routine nature of thoracic transplantation might allow a suboptimal pulmonary artery anastomosis after heart or lung transplantation to go undetected as a potential cause of pulmonary graft dysfunction or donor heart right ventricular dysfunction.Kumar and colleagues' suggestion of TEE Doppler interrogation of the flow characteristics across the anastomosis after lung transplantation could provide early evidence of a technical problem. If TEE is not routinely used for lung transplant operations, the anticipation of important pulmonary artery size disparity should at least stimulate consideration with our anesthesia colleagues for insertion of a TEE probe for anastomotic examination. The author reported no conflicts of interest.The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest. The author reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest. In their recent letter to the Editor, Kumar and colleagues1Kumar N. Flores A.S. Hussain N. Ganapathi A.M. Whitson B.A. Essandoh M.K. et al.Ensuring pulmonary artery patency in donor-recipient size mismatch: a collaborative challenge.J Thorac Cardiovasc Surg Tech. 2022; 15: 206-207Scopus (4) Google Scholar provided an important suggestion for additional evaluation of the pulmonary artery anastomosis after lung transplantation with transesophageal echocardiography (TEE) in the operating room. We thank Yokoyama and colleagues2Yokoyama Y. Chen-Yoshikawa T.F. Nakajima D. Ohsumi A. Date H. Various techniques for anastomosis of pulmonary arteries with size mismatch during lung transplantation.J Thorac Cardiovasc Surg Tech. 2021; 9: 192-194Scopus (7) Google Scholar for their previous article on anastomotic techniques that again highlight the importance of a technically optimal operation, which includes an unobstructed pulmonary artery anastomosis. The routine nature of thoracic transplantation might allow a suboptimal pulmonary artery anastomosis after heart or lung transplantation to go undetected as a potential cause of pulmonary graft dysfunction or donor heart right ventricular dysfunction. Kumar and colleagues' suggestion of TEE Doppler interrogation of the flow characteristics across the anastomosis after lung transplantation could provide early evidence of a technical problem. If TEE is not routinely used for lung transplant operations, the anticipation of important pulmonary artery size disparity should at least stimulate consideration with our anesthesia colleagues for insertion of a TEE probe for anastomotic examination. Ensuring pulmonary artery patency in donor-recipient size mismatch: A collaborative challengeJTCVS TechniquesVol. 15PreviewThe vascular anastomoses of lung transplantation are a growing area of interest. Anastomosing the donor and recipient pulmonary artery (PA) segments is among the most delicate aspects of the surgery, and proper surgical technique is critical to allograft and patient survival. Obstruction of blood flow through the PA may cause graft ischemia, refractory hypoxemia, right ventricular dysfunction, and even death in affected patients.1 However, the importance of the PA anastomoses has yet to be critically examined in the lung transplant literature. Full-Text PDF Open Access

An Analysis by the European Committee on Organ Transplantation of the Council of Europe Outlining the International Landscape of Donors and Recipients Sex in Solid Organ Transplantation.

Discrepancies in donation and transplantation by sex and gender have previously been reported. However, whether such differences are invariably the inevitable, unintended outcome of a legitimate process has yet to be determined. The European Committee on Organ Transplantation of the Council of Europe (CD-P-TO) is the committee that actively promotes the development of ethical, quality and safety standards in the field of transplantation in Europe. Whilst the ultimate objective is to shed light on the processes underlying potential gender inequities in transplantation, our initial goal was to represent the distribution by sex among organ donors and recipients in the CD-P-TO Member States and observer countries. Our survey confirms previous evidence that, in most countries, men represent the prevalent source of deceased donors (63.3% in 64 countries: 60.7% and 71.9% for donation after brain and circulatory death, respectively). In contrast, women represent the leading source of organs recovered from living kidney and liver donors (61.1% and 51.2% in 55 and 32 countries, respectively). Across countries, most recovered organs are transplanted into men (65% in 57 countries). These observations may be explained, at least in part, by the higher burden of certain diseases in men, childbearing related immune sensitization in women, and donor-recipient size mismatch. Future research should establish whether gender-related socially-constructed roles and socioeconomic status may play a detrimental role reducing the access of women to transplantation.

Diaphragmatic plication among lung transplant patients: A single-center experience.

There is lack of data reporting outcomes among patients needing diaphragmatic plication (DP) during or after lung transplantation (LT). We sought to assess the association of DP with post-transplant spirometry among other outcomes. We included all patients who underwent LT between 2012 and 2016 (n=324, mean age 56.3±13.4 years; M:F 198:126). We compared early and late outcomes based on the need for DP. The frequency of diaphragmatic dysfunction (DD) on pre-transplant fluoroscopy was 52.2%. A total of 38 DP procedures were performed among 37 patients (11.4% of LT patients). DP was done for anatomic (sizing or spacing issues) or functional indications (symptomatic DD). While patients with DP had significantly lower spirometry throughout the 3-year follow-up period, their slope of decline, functional assessments at the first annual visit, the risk of CLAD, and mortality were similar to patients without DP. A sub-group analysis limited to patients with restrictive lung diseases as the transplant indication had similar findings. Pre-transplant DD is common among LT candidates although it did not predict the need for DP. DP may be performed for functional or anatomic indications especially for addressing the donor-recipient size mismatch. Despite the lack of favorable effect on post-transplant spirometry, patients undergoing DP have acceptable and comparable early and late outcomes.

Donor-Recipient Size Mismatch, Donor Age and Interstitial Lung Disease Are Associated with Abnormal Reactance, Resistance and Airway Closure After Bilateral Lung Transplantation

<h3>Purpose</h3> The effect of donor-recipient demographics and features on recipient lung mechanics after transplantation (LTx) is unknown. The Forced Oscillation Technique (FOT) measures the mechanical properties of the respiratory system. We have recently developed novel analyses of FOT parameters that assess airway closure. This study aims to assess the effect of donor and recipient clinical history on recipient respiratory system mechanics post LTx using FOT. <h3>Methods</h3> Bilateral LTx recipients were recruited into a multi-centre (Alfred Hospital, Melbourne and St Vincent's Hospital, Sydney) prospective study. Subjects underwent spirometry, plethysmography and FOT (Tremoflo 2000, Thorasys, Canada) on one occasion at 3-6 months after LTx. Donor lung size was estimated from predicted total lung capacity equations. General linear models were used to assess the effect of donor-recipient demographics and features on respiratory mechanics from FOT. <h3>Results</h3> A total of 63 patients (52% male, age 52 ±15yrs) were included. Oversized donor lungs (donor predicted TLC > recipient TLC pre-Tx) were associated with increased respiratory reactance (Xrs5, p=0.041) and increased peripheral airway resistance (R5-19, p=0.002). Undersized donor lungs (donor predicted TLC < recipient TLC pre-Tx) were associated with increased total and peripheral airway resistance (R5 and R5-19, p=0.043 and p=0.003) and markers of early airway closure from FOT (Xrs5 and DR1, p=0.047 and p=0.038). Recipients transplanted for interstitial lung disease (ILD) were more likely to have increased total and peripheral airway resistance (R5 and R5-19, p=0.035 and p=0.038). Increasing donor age was more associated with airflow limitation (FER, p=0.009) and peripheral airway resistance (R5-19, p=0.042). <h3>Conclusion</h3> LTx recipients who receive over or under-sized donor lungs, older donor lungs, or had ILD as their native lung disease were more likely to have abnormal respiratory system mechanics. Longitudinal assessment is required to understand the trajectory of novel oscillometry parameters, including FOT, in relation to lung allograft dysfunction.

Dynamics of Donor-Derived Cell-Free DNA at the Early Phase After Pediatric Kidney Transplantation: A Prospective Cohort Study

Background: Donor-derived cell-free DNA (ddcfDNA) has been suggested as an indicator of allograft injury in adult and pediatric kidney transplantation (KTx). However, the dynamics of ddcfDNA in pediatric KTx have not been investigated. In addition, it has not been demonstrated whether donor-recipient (D/R) size mismatch affect ddcfDNA level.Methods: Pediatric KTx recipients with a single donor kidney were enrolled and followed up for 1 year. ddcfDNA, calculated as a fraction (%) in the recipient plasma, was examined longitudinally within 3 months post-transplant. D/R size mismatch degree was described as D/R height ratio. The 33rd percentile of D/R height ratio (0.70) was used as the cut-off to divide the patients into low donor-recipient height ratio group (<0.70) and high donor-recipient height ratio group (≥0.70). The dynamics of ddcfDNA were analyzed and the impact factors were explored. Stable ddcfDNA was defined as the first lowest ddcfDNA. ddcfDNA flare-up was defined as a remarkable elevation by a proportion of >30% from stable value with a peak value >1% during elevation.Results: Twenty-one clinically stable recipients were enrolled. The median D/R height ratio was 0.83 (0.62–0.88). It took a median of 8 days for ddcfDNA to drop from day 1 and reach a stable value of 0.67% (0.46–0.73%). Nevertheless, 61.5% patients presented ddcfDNA>1% at day 30. Besides, 81.0% (17/21) of patients experienced elevated ddcfDNA and 47.6% (10/21) met the standard of ddcfDNA flare-up. Donor-recipient height ratio was an independent risk factor for ddcfDNA flare-up (odds ratio = 0.469 per 0.1, 95% CI 0.237–0.925, p = 0.029) and low donor-recipient height ratio (<0.70) was found to increase the risk of flare-up occurrence (odds ratio = 15.00, 95% CI 1.342–167.638, p = 0.028).Conclusions: ddcfDNA rebounds in many stable pediatric KTx recipients without rejection. This may be induced by significant D/R size mismatch and may affect its diagnostic performance at the early phase after pediatric KTx in children.

Abstract 12426: Influence of Body Mass Index in Donor Recipient Size Mismatch in Pediatric Heart Transplantation

Introduction: Body weight has been the traditional metric for matching donor and recipient size for pediatric heart transplantation (pHT). However, the impact of such mismatch is not well established. We hypothesized that mismatch in compound measures such as body mass index (BMI) or body surface area (BSA) rather than weight, may impact outcomes of pHT and therefore should be used for donor-recipient size matching. Methods: Analysis of the United Network for Organ Sharing database limited to pHT recipients was performed. Donor and recipient mismatch tertiles were created for weight, BMI, and BSA ratios. Differences in recipient characteristics between each tertile were studied using univariate analysis. Multivariable analysis was used to assess the impact of each mismatch on one-year survival. Kaplan Meier analysis was used to assess overall survival. Results: A total of 4,465 pHT patients were available and included in the analysis of which 43% had congenital heart disease (CHD). Overall, those with low donor-recipient ratio for BMI were more likely to be younger recipients, less likely to be Caucasian and be on ECMO (all p&lt;0.01). In both CHD and non-CHD cohorts, multivariable regression analysis showed that use of ECMO (CHD OR 3.97; non-CHD OR 3.24), presence of liver dysfunction (CHD OR 1.10; non-CHD OR 1.11), and low donor to recipient BMI ratio (compared to normal) (CHD OR 1.70; non-CHD OR 2.28) were the only predictors of one-year mortality (all p &lt;0.001). Low BMI ratio was also associated with worse long-term survival in non-CHD groups, but not in the CHD cohort. This finding probably reflects inferior overall outcomes in the CHD cohort. Weight and BSA ratio did not predict one year or long-term survival. Conclusions: Traditional matching practice using weight may be inadequate and use of BMI matching may provide improved donor-recipient matching. Use of low BMI donors compared to recipients may predict poor early and long-term survival and therefore should be avoided in pediatric heart transplantation. Further refinement of matching may be needed in specific recipient populations.

Perioperative anesthesia care for the pediatric patient undergoing a kidney transplantation: An educational review.

Living‐donor kidney transplantation is the first choice therapy for children with end‐stage renal disease and shows good long‐term outcome. Etiology of renal failure, co‐morbidities, and hemodynamic effects, due to donor‐recipient size mismatch, differs significantly from those in adult patients. Despite the complexities related to both patient and surgery, there is a lack of evidence‐based anesthesia guidelines for pediatric kidney transplantation. This educational review summarizes the pathophysiological changes to consider and suggests recommendations for perioperative anesthesia care, based on recent research papers.

Reply: Ensuring pulmonary artery patency in donor–recipient size mismatch: A collaborative challenge

Vascular anastomosis during lung transplantation is a critical issue that directly affects postoperative graft function. The use of transesophageal echocardiography (TEE) to establish clear criteria for a possible size mismatch between donor and recipient pulmonary artery (PA) diameters at the time of lung transplantation, as reported by Kumar and colleagues1 in this study, is a method that holds great promise for the future. We introduced 4 new PA vascular anastomosis techniques that could be implemented upon recognition of a size mismatch in PA diameter at the time of lung transplantation; however, we failed to discuss how a surgeon may optimize technique selection.