Effect of propofol on brain injury in children undergoing open heart surgery under cardiopulmonary bypass

Objective To investigate the effect of propofol on the brain injury in children undergoing open heart surgery under cardiopulmonary bypass (CPB).Methods Thirty children aged 4-10 yr undergoing repair of ventricular septal defect or atrial septal defect under CPB were randomly divided into 2 groups ( n = 15 each):control group (group C) and propofol group (group P). Anesthesia was induced with iv injection of sufentanil 1 μg/kg, propofol 2.5 mg/kg (midazolam 0.2 mg/kg in group C) and pipecuronium 0.1 mg/kg in group P. Anesthesia was maintained with iv infusion of 1％ propofol 6 mg·kg-1 ·h-1 (0.05％ midazolam 0.2 mg·kg-1 ·h-1 in group C) until the end of operation. Isoflurane ( 1％-2％ ) were inhaled during the operation in all patients. Sufentanil 1 μg/kg and pipecuronium 0. 1 mg/kg were injected intravenously after the start of CPB. A catheter was inserted into right internal jugular vein and advanced cephalad until jugular bulb for blood sampling before CPB, at 30 min of CPB, at the end of CPB, at 30 min after termination of CPB, at the end of operation, and at 24 h after termination of CPB to detect the plasma concentrations of 8-iso-PGF2 and S-100β by ELISA. Arterial and jugular bulb venous blood samples were collected for determination of SjvO2 before CPB, when naso-pharyngeal temperature was reduced to 30 ℃, when naso-pharyngeal temperature returned to 36 ℃ and at the end of CPB. Cerebral arterial venous oxygen content differences ( Da-jvO2 ) and cerebral oxygen extraction rate of oxygen ( CEO2 ) were calculated. Results Plasma concentrations of 8-iso-PGF2α and S-100β were significantly lower, SjvO2 was significantly higher, Da-jvO2 and CEO2 were significantly lower in group P than in group C (P ＜ 0.05＝. ConclusionPropofol can reduce the brain injury in children undergoing open heart surgery during CPB and the mechanism is related to decrease in cerebral oxygen metabolic rate and lipid peroxidation. Key words: Propofol; Gardiopulmonary bypass; Brain; Cardiac surgical procedures