RESUMEN
Objective To investigate the effect of dexmedetomidine on renal function during percutaneous nephrolithotomy under general anesthesia in the patients with renal calculus. Methods Thirty patients (male 25 cases,female 5 cases)with renal calculi,age 40-70 yr,with body mass index of 1 9-27 kg/m2 ,ASA physical status Ⅰ or Ⅱ,scheduled for elective percutaneous neph-rolithotomy under general anesthesia,were randomized into two groups (n =1 5 each):control group (group C)and dexmedetomidine group (group D).In patients of group D,dexmedetomidine 1 μg/kg were infused intravenously over 10 min before induction anesthesia,followed by infusion at a rate of 0.5 μg·kg-1 ·h-1 until the end of operation.The equal volume of normal saline was given in pa-tients of group C.Immediately before beginning of surgery (T0 ),at the end of surgery (T1 ),the first day after surgery (T2 )and the third day after surgery (T3 ),blood and urine samples were obtained. The serum and urine concentrations of urea nitrogen (BUN),serum creatinine (Scr),cystatin C (CYS-C),retinol binding protein (RBP),urinaryα1-microglobulin (α1-MG),urine micro-albumin,u-rinary transferrin,urinary immunoglobulin G was measured by automatic biochemical analyzer and Beckman specific protein analyzer.Results There was no difference in BUN and Scr at any time point between the two groups.Compared with T0 ,CYS-C and RBP at T1-T3 increased significantly in two groups (P <0.05).The levels of CYS-C and RBP in group D were lower than in group C at T1-T3 (P<0.05).There was no difference in urinary immunoglobulin G,urine micro-albumin after the start of surgery.Compared with T0 ,urinary α1-MG at T1-T3 increased significantly in two groups (P <0.05).The level of urinary α1-MG in group D was lower than in group C at T1-T3 (P < 0.05 ). Conclusion Dexmedetomidine(1 μg/kg infused intravenously before induction of anesthesia,followed by infusion at a rate of 0.5 μg·kg-1 ·h-1 until the end of operation)might provide renal protection to some extent during percutaneous nephrolithotomy under general anesthesia in the patients with renal calculi.