Efficacy of dialysis in peritoneal dialysis: utility of bioimpedance to calculate Kt/V and the search for a target Kt.

BACKGROUND: To calculate Kt/V, volume (V) is usually obtained by Watson formula, but bioimpedance spectroscopy (BIS) is a simple and applicable technique to determinate V, along with other hydration and nutrition parameters, in peritoneal dialysis (PD) patients. Dialysis efficacy can also be measured with Kt, but no experience exists in PD, so there is no reference/target value for Kt that must be achieved in these patients to be considered adequately dialyzed. We evaluated the efficacy of PD with Kt/V using Watson formula and BIS for V calculation, assessed hydration status in a PD unit by data obtained by BIS, and attempted to find a reference Kt from the Kt/V previously obtained by BIS. METHODS: In this observational prospective study of 78 PD patients, we measured V using BIS (V bis) and Watson formula (V w) and calculated weekly Kt/V using both volumes (Kt/V bis/V bis and Kt/V w). With the BIS technique, we obtained and subsequently analyzed other hydration status parameters. We achieved a reference Kt, extrapolating the value desired (weekly Kt/V 1.7) to the target Kt using the simple linear regression statistical technique, basing it on the results of the previously calculated Pearson's linear correlation coefficient. RESULTS: Volume was 1.8 l higher by Watson formula than with BIS (p < 0.001). Weekly Kt/V bis was 2.33 ± 0.68, and mean weekly Kt/V w was 2.20 ± 0.63 (p < 0.0001); 60.25 % of patients presented overhydration according to the BIS study (OH >1.1 l). The target value of Kt for the reference weekly Kt/V bis (1.7) was 64.87 l. CONCLUSIONS: BIS is a simple, applicable technique for calculating V in dialysis that can be especially useful in PD patients compared with the anthropometric formulas, by the abnormally distributed body water in these patients. Other parameters obtained by BIS will serve to assess both the distribution of body volume and nutritional status in the clinical setting. The target Kt value obtained from Kt/V bis allowed us to measure the efficacy of PD in a practical way, omitting V measurement.

[Short cold ischaemia time optimises transplant results for kidneys from expanded criteria donors]. / El tiempo de isquemia fría corto optimiza los resultados de los trasplantes renales efectuados con donantes con criterios expandidos.

INTRODUCTION: Outcome of renal transplant from expanded criteria donors (ECD) is usually inferior than those from standard criteria donors (SCD) and may be improved decreasing cold ischemia time (CIT) and minimizing preservation injury. We compare the results obtained with CIT <15 hours in kidney transplants from ECD vs SCD. SUBJECTS AND METHODS: Prospective, single center study of kidney transplants performed since June 2003 to December 2007. Minimum follow-up period was 12 months. Data of donors, receptors and transplant outcome from ECD and SCD are compared. RESULTS: CIT (mean +/- SD) was 9.3+/-2.5 hours in transplants from ECD (n=24) and 8.3+/-3.3 hours in those from SCD (N=50), p=0.18. We did not find significant differences among recipients of grafts from ECD and those from SCD regarding: primary non-function (4.2% vs 2%, respectively), delayed graft function (16.7% vs 10%), surgical complications (25% vs 16%) or acute rejection episodes (8.3% vs 2%). Glomerular filtration rate at one year follow-up was 65.8+/-14.9 ml/min in ECD recipients and 49.4+/-12.5 ml/min (p<0.0001). One year graft survival was 95.8% in ECD recipients and 94% in SCD recipients (p=0.75). CONCLUSIONS: Short CIT in kidney transplant from ECD leads to similar outcome than that obtained from SCD, although renal function is inferior in ECD grafts.

Analysis of Kidney Donation and Its Relationship With Graft Failure of the Recipient at 1 Year.

INTRODUCTION: Currently, the shortage of organs available for kidney transplantation and a change in donors' and recipients' profiles (elderly, with cardiovascular risk, donors after cardiac death), it is becoming necessary to assess grafts from expanded-criteria donors (ECD) in order to have methods that allow us to predict viability and graft survival. OBJECTIVE: The aim of this study was to analyze the different methods of renal donor assessment (estimated glomerular filtration rate [eGFR], preimplantation biopsy, and Kidney Donor Profile Index [KDPI] score) as predictors of graft survival and renal function of our recipient at 1 year. METHODS: We performed a descriptive and retrospective study of 183 deceased donor kidney transplantations performed at our center between 2011 and 2015. We calculated the KDPI scores, donor eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration Formula equation, and biopsies were evaluated using Banff classification. RESULTS: ECDs comprised 59.60%, 93% of donors had an eGFR ≥ 60 mL/min/1.73 m2, and 41% presented with a KDPI score ≥ 90%. The most frequent range in the biopsy score was 0-3. The 1-year graft survival rate was 86.90%. Factors that negatively influenced graft survival were donor/recipient age, ECD, KDPI, and cold ischemia time (CIT). CONCLUSION: Prolonged CIT and KDPI ≥ 90% were donor variables that were related to graft failure at 1 year in our center.

El tiempo de isquemia fría corto optimiza los resultados de los trasplantes renales efectuados con donantes con criterios expandidos / No disponible

Introducción: Los resultados de los trasplantes efectuados condonantes con criterios expandidos (DCE) son inferiores a los obtenidos con donantes con criterios estándar (DCS). Para optimizar su evolución, se podría reducir su tiempo de isquemiafría (TIF) reduciendo su daño de preservación. Comparamoslos resultados obtenidos al aplicar TIF <15 horas tanto a DCE como a DCS. Material y métodos: Realizamos un estudio unicéntrico, de cohortes, prospectivo, de casos incidentes de trasplante renal de cadáver entre junio de 2003 y diciembre de2007. El tiempo mínimo de seguimiento fue de 12 meses. Comparamos los datos de los donantes, de los receptores y de la evolución de los trasplantes efectuados con DCE frente a los de los DCS. Resultados: El TIF para los DCE (N = 24) y para los DCS (N = 50) fue, respectivamente, de 9,3 ± 2,5 y 8,3± 3,3 horas (p = 0,18). No encontramos diferencias significativas entre los receptores de DCE y DCS en cuanto a: no función primaria del injerto 4,2 vs. 4%, retardo en la función del injerto 16,7 vs. 10%, complicaciones quirúrgicas 25 vs. 16% y rechazos agudos 8,3 vs. 2%. El filtrado glomerular estimado al año para los DCS fue de 65,8 ± 14,9 ml/min y para los DCE de 49,4 ± 12,5 ml/min (p <0,0001). La supervivencia renal al año fue del 95,8% para los receptores de DCE y del 94% para los DCS (p = 0,75). Conclusiones: La aplicación de TIF cortos a los DCE permite conseguir una evolución similar a la de los DCS, aunque su función renal sea en todo momento inferior (AU)

Introduction: Outcome of renal transplant from expanded criteria donors (ECD) is usually inferior than those from standard criteria donors (SCD) and may be improved decreasing cold ischemia time (CIT) and minimizing preservation injury. We compare the results obtained with CIT <15 hours in kidney transplants from ECD vs. SCD. Subjects and Methods: Prospective, single center study of kidney transplants performed since June 2003 to December 2007. Minimum follow-up period was 12months. Data of donors, receptors and transplant outcome from ECD and SCD are compared. Results: CIT (mean ± SD)was 9.3 ± 2.5 hours in transplants from ECD (n = 24) and8.3 ± 3.3 hours in those from SCD (N = 50), p = 0.18. We did not find significant differences among recipients of grafts from ECD and those from SCD regarding: primary non-function (4.2% vs. 2%, respectively), delayed graft function (16.7% vs. 10%), surgical complications (25% vs.16%) or acute rejection episodes (8.3% vs. 2%).Glomerular filtration rate at one year follow-up was 65.8± 14.9 ml/min in ECD recipients and 49.4 ± 12.5 ml/min (p<0.0001). One year graft survival was 95.8% in ECD recipients and 94% in SCD recipients (p = 0.75).Conclusions: Short CIT in kidney transplant from ECD leads to similar outcome than that obtained from SCD, although renal function is inferior in ECD grafts (AU)