Intraoperative resistance index measured with transsonic flowmeter on kidney graft artery can predict early and long-term graft function

Abstract

Introduction: Resistive index (RI) measured by Doppler sonography in the early period after kidney transplantation is a well-known predictor of kidney transplant outcome. The purpose of this study was to analyze the impact of RI values calculated intraoperatively in renal allograft artery using transit time flowmetry (TTF) on both early and long-term kidney graft function.

Material and methods: TTF was performed on 72 patients who received kidney grafts fed by a single artery. TTF was performed before wound closure. We excluded patients with an early acute rejection (n=8), an early graft loss (n=2), or primary graft nonfunction (n=1). Recipients were divided into RI tertile groups. The initial kidney graft function was defined as immediate (IGF), slow or delayed. Kidney graft estimated glomerular filtration rate (eGFR) was analyzed upon long-term follow-up.

Results: Patients with a low RI (<0.57) showed the highest incidence of immediate graft function (65% versus 5.3%), whereas the high RI group (>0.70). Show the most frequent rate of delayed graft function (52.6% versus 15%). Recipients with low RI values displayed significantly better eGFR (by at least 12 mL/min/1.73 m2) than those with medium or high RI values at all analyzed times; subjects with medium or high RI showed similar eGFR at 48-months.

Conclusion: An high RI value measured intraoperatively was a valuable predictor of inferior early and long-term kidney graft function.