Enzyme Biomarkers of Renal Tubular Injury in Arterial Surgery Patients

Abstract

Objective: The aim of this study was to verify whether preoperative diabetes, hypertension, and renal function had any relationship with postoperative tubule function in patients submitted to anesthesia for arterial surgery. Methods: Prospective observational study. One hundred and forty-four patients submitted to anesthesia for arterial surgery enrolled consecutively and divided into four groups: G1 -diabetes and hypertension; G2 -diabetes; G3 -hypertension; and G4 -without hypertension or diabetes. Urine was obtained for laboratory analysis of urinary creatinine (Ucr), alkaline phosphatase (AP), g-glutamyltransferase (gGT), and blood for cystatin C and creatinine before the surgery (M1) and 24 h after the surgery (M2). Results: Values of gGT, gGT/Ucr, and AP × gGT/Ucr increased at M2 in G4. Patients without renal function compromise (GFR ≥90 mL/min/1.73 m 2 ) presented increased gGT/Ucr and AP × gGT/Ucr values at M2 and those with slightly compromised renal function (60-89 mL/min/1.73 m 2 ) presented increased gGT values at M2. There was no correlation between deltaCystatin C and deltaAP, deltagGT, deltagGT/Ucr, deltaAP/Ucr, and deltaAP × gGT/Ucr. Conclusions: Diabetes, hypertension, and preoperative renal function seem to interfere in tubular enzymuria immediately after surgery in arteriopathic patients. However, when these markers do not increase in postoperative period, renal dysfunction cannot be discarded.