OBJECTIVESome research has shown that ambroxol can alleviate lung injury induced by cardiopulmonary bypass (CPB). However, whether ambroxol has protective effects against CPB-induced renal injury remains unknown. This study investigated the effect of ambroxol on renal function in children undergoing CPB.

METHODSForty children at ages of 3-8 years with cardiac function class I or II and weighing 12-25 kg, underwent repair of ventricular septal defect (VSD) under CPB. They were randomly divided into two groups (n=20 each):control and ambroxol-treated. The children in the ambroxol-treated group received ambroxol of 4.5 mg/kg in 10 mL normal saline by intravenous injection after skin incision. The control group received 10 mL of normal saline instead. Serum concentrations of urea nitrogen (BUN), beta(2)-microglobulin (beta(2)-MG) and creatinine (Cr) and urinary beta(2)-MG, retinol-binding-protein (RBP) and N-acetyl-beta-D-glucosaminidase (NAG) were measured before operation, and 2, 12, 24 and 48 hrs after operation.

RESULTSSerum Cr and urinary beta(2)-MG concentrations 2 hrs after operation, serum beta(2)-MG concentration 2 and 12 hrs after operation, urinary RBP concentration 2, 12, 24 and 48 hrs after operation, and urinary NAG concentration 2, 12 and 24 hrs after operation in the control and the ambroxol-treated groups increased significantly as compared with their baseline values (before operation) (P<0.05). Serum Cr concentration 2 hrs after operation, serum beta(2)-MG and urinary beta(2)-MG concentrations 2 and 12 hrs after operation, urinary RBP concentration 2, 12, 24 and 48 hrs after operation, and urinary NAG concentration 12 and 24 hrs after operation in the ambroxol-treated group were significantly lower than those in the control group (P<0.05).

CONCLUSIONSAmbroxol administration before CPB is effective in reducing CPB-induced renal injury in children undergoing repair of VSD. Further research is required to understand the mechanism.