Effect of Different Rates of Infusion of Dexmedetomidine on Upper Brachial Plexus Surgery Lactate,Malondialdehyde and Ischemic Modified Protein

Objective To explore the effect of dexmedetomidine with different infusion rates of infusion of dexmedetomidine on upper brachial plexus sugery lactate,malondialdehyde and ischemic modified protein. Methods 60 patients undergoing elective upper limb surgery were randomly divided into dexmedetomidine Group A( 0. 5 μg / kg·h),Group B( 1. 0 μg / kg·h),Group C( the control group,with normal saline),with 20 patients in each group. All patients' brachial plexus block were treated with 30 m L 0. 33% ropivacaine and 0. 67%lidocaine. After blocking and 10 min before operation,the patients were infused with dexmedetomidine 0. 5 μg per kg,then dexmedetomidine were kept different infusion rates in different groups: Group A( 0. 5 μg / kg·h),Group B( 1. 0 μg / kg·h),Group C( volume physiological saline). To determine arterial blood lactic acid( a Lac),malonaldehyde( MDA) and ischemia modify albumen( IMA) by collecting blood sample at preoperation( T1),15 min after brachial plexus blocking( T2),5 min and 30 min after loose tourniquet( T3 and T4). The plasma MDA and IMA concentration was measured. The patients' blood pressure,heart rate,Sp O2 and complications were recorded. Results The blood pressure and heart rate in group C at T3 ~ 4 and in group A,Bat T2 ~ 4 decreased compared with T1. The a Lac,MDA and IMA in all groups at T3 ~ 4 increased compared with T1( P 0. 05). The heart rate in group A,Bat T4 decreased compared with group C. The a Lac,MDA and IMA in group A,B at T3 ~ 4 decreased compared with group C( P 0. 05). The a Lac,MDA and IMA in group B at T3 ~4 decreased compared with group A( P 0. 05). Conclusion Dexmedetomidine has significant effect on patients undergoing upper brachial plexus surgery in a infusion rate- dependent manner. And protective effect can be increased with the rates of infusion of dexmedetomidine.