Effects of dexmedetomidine on cerebral oxygen metabolism and postoperative cognitive function during cardiopulmonary bypass of pediatric congenital heart disease surgery

Abstract

Objective Exploring the effects of dexmedetomidine(Dex) on cerebral oxygen metabolism and postoperative cognitive function during cardiopulmoary bypass of pediatric congenital heart disease(CHD) surgery. Methods Eighty-four children with cardiopulmonary bypass of CHD surgery were randomly divided into observation group and control group(n=42). 2.5% sevoflurane and Dex 0.4 μg·kg-1·h-1 was applied during maintenance of anesthesia in observation group, while only 2.5% sevoflurane was applied in control group. At the time points of before beginning cardiopulmonary bypass(T1), of the ascending aorta was open(T2), of ending cardiopulmonary bypass(T3) and of 6 hours after operation(T4), blood from radial artery and right jugular bulb were harvested for blood gas analysis. The jugular venous oxygen saturation(SjvO2), arterial venous oxygen content difference(Da-jvO2) and cerebral extraction of oxygen(CERO2) were calculated according blood gas analysis. The mini-mental state examination(MMSE) score were evaluated before and 4 day, 3 month and 1 year after surgery. Results The SjvO2 of T2 were higher than SjvO2 of T1 in two groups, but Da-jvO2 and CERO2 were lower than Da-jvO2 and CERO2 of T1. The differences were statistically significant(P 0.05). There were no significant differences in preoperative MMSE scores between two groups(P>0.05). The MMSE scores in observation group at 4 day and 3 month after surgery were (26.5±1.5), (27.6±1.6), which were significantly higher than those in control group[(24.3±1.3), (25.8±1.5)], and the differences were statistically significant(P 0.05). Conclusions Dex could improve cerebral oxygen metabolism and postoperative cognitive function during cardiopulmonary bypass of pediatric CHD surgery. Key words: Dexmedetomidine; Cardiopulmonary bypass; Oxygen metabolism; Cognitive function