Effects Of Different Administration Timing Of Butorphanol On Oxidative Stress And Inflammatory Response Of Ischemia-Reperfusion Injury Induced By Orthopaedic Tourniquet

Objective:To investigate the effects of different administration timing of butorphanol on oxidative stress and inflammatory response of ischemia-reperfusion injury induced by orthopaedic tourniquet.Methods:From the second hospital of Shanxi Medical University,90 patients who underwent elective lower extremity orthopedic surgery from May 2020 to may 2021 were obtained,with unlimited gender and age ranging from 20 to 70 years old.ASA grade I～II,the patients were randomly divided into butorphanol pretreatment group（Group y）,butorphanol post-treatment group（Group H）and control group（Group C）,with 30 patients in each group receiving subarachnoid block.Patients in group Y received a slow bolus of0.02 mg/kg butorphanol intravenously 5 min before the tourniquet was inflated;A slow bolus of 0.02 mg/kg butorphanol was administered intravenously to patients in group H 5min before the tourniquet was deflated;Patients in group C were not specifically addressed.Mean arterial pressure（MAP）,heart rate（HR）,saturation of pulse oximetry（Sp O₂）values were compared T₀（before loading medication）,T₁（30 min after tourniquet inflation）,T₂（60 min after tourniquet inflation）and T₃（5 min after tourniquet deflation）.And the venous blood at two-time points of T₀and T₃was taken to detect serum malondialdehyde（MDA）,Superoxide dismutase（SOD）,and tumor necrosis factor-α（TNF-α）.Results:There was no significant difference in HR,MAP and Sp O₂at each time point among the three groups,and there was no significant difference in HR and Sp O₂at each time point within the group.Compared with T₀,MAP in group H and group C increased significantly at T₂,decreased significantly at T₃,and decreased significantly at T₃in group Y（P<0.05）.Compared with T₀,the levels of MDA and TNF-αin serum of patients in T₃increased,and the level of SOD in serum decreased（P<0.05）.At T₃,the levels of serum MDA and TNF-αin group Y and group H were significantly lower than those in group C,and the level of serum SOD was significantly higher than that in group C（P<0.05）.However,there was no significant difference in the concentrations of serum MDA,SOD and TNF-αbetween group Y and group H.Conclusions:Butorphanol pretreatment and post-treatment can effectively reduce the ischemia-reperfusion injury caused by tourniquet,which may be related to the inhibition of oxidative stress and inflammatory response.