Poster 15. Post-operative Duplex ultrasound predicts early complications and renal function after kidney transplantation

Thursday 14 march 2019

13:12 - 13:15h

Categories: Klinisch, Postersessie

Parallel session: Postersessies 3 - Clinical

A. van de Kuit1, S. Benjamens1, S.P. Berger2, J.S.F. Sanders2, D. Yakar3, R.A. Pol1

1Dept. of Transplant Surgery,2Dept. of Internal Medicine,  3Medical Imaging Center, University Medical Center Groningen, The Netherlands.

Background: Assessing early complications after kidney transplantation (KTX) remains difficult. The renal resistive index (RI) is used to differentiate between normal and abnormal functioning allografts after KTX. However, the clinical applicability in the post-operative setting is insufficiently determined and conflicting data concerning the short-term allograft outcomes are reported. In the current study, the clinical value of the RI with emphasis on surgical complications, one-year kidney function (measured(m)GFR) and one-year patient survival is assessed.

Methods: We performed a single-center, retrospective case-control study. All patients (N=344) who underwent KTX between November 2015 and July 2017 were included. Duplex ultrasound was performed within 24 hours after KTX on the post-anaesthesia care unit. The RI was calculated as: (peak systolic velocity–end diastolic velocity)/peak systolic velocity and is defined as the mean of a measurement in the artery of the upper pole, between the poles and the lower pole. Surgical complications were classified using the Comprehensive Complication Index (CCI).

Results: The mean intrarenal RI was 0.64 ± 0.08. The RI was significantly higher in donation after brain death (DBD) and cardiac death (DC) kidney grafts compared to living donor kidneys (respectively 0.66 and 0.67 vs. 0.62, p<0.001). One-year patient survival was lower in patients with a RI>0.70 than in patients with a RI≤0.70 (p=0.029). The median CCI in kidney transplant recipients was 8.7 [IQR 0-21]. The median CCI was higher in patients with a RI>0.70 compared to patients with a RI≤0.70 (respectively 8.7 vs 12.2, p=0.012). The RI was negatively correlated with one-year mGFR (r=-0.14, p=0.030). In a stepwise linear regression model, recipient age (β=0.21, p<0.001), cold ischemia time (β=0.21, p<0.001) and diastolic blood pressure (β=-0.18, p<0.001) were factors associated with the RI, independent of important confounders (recipient and donor gender and BMI, donor age, recipient smoking status, systolic blood pressure, antihypertensive use, type of donation, the presence of acute tubular necrosis and delayed graft function).

Conclusions: This study showed that a RI>0.70 is associated with a higher CCI, a lower mGFR and a worse one-year patient survival. Also different measurements were determined between deceased and living kidney grafts. The association is most likely determined by worse cardiovascular system of the patients. We suggest taking these factors into consideration when interpreting post-operative duplex ultrasound.