Breast Cancer Surgery, Propofol Peroxidation - Antioxidant

Objective: We studied the effect of propofol on superoxide dismustase(SOD), total antioxidant capacity (T-AOC) and malonydialdehyde (MDA)In breast cancer patients during radlcal operation under propofol andisoflurane anesthesia with different oxygen concentrations, In order toreveal the antioxidative effect of pfopofol and select the proper oxygenconcentration.Methods: 32 Selected breast cancer patiens, receiving redical operation,ASAⅠ-Ⅲ, Were randomly divided into 4 groups (n=8). A and B groupswere propofol groups, inhaling oxygen concentrations were 100％O₂and 30％O₂, respectively. C and D groups were isoflurance groups,Inhaling 100％O₂ and 30％O₂ mixed with 70％N₂O, respectively. Werecorded SBP, DBP, HR and SpO₂ of all patients before anesthesia (T₁),brfore (T₂) and after intubation (T₃), after incision (T₄), one hour afteranesthesia (T₅), respectively. MDA level and SOD, T-AOC activitieswere measured before anesthesia (T₁') , one hour after Intubation (T₂')and at the end of operation (T₃'). Venus bloods samples of 10 heahhywomen were collected as control E group.Results: 1. In breast cancer patients, MDA level was higher while SOD,T-AOC activities were lower than those of healthy women. 2. Allpatients' blood dynamics were stable, blood pressure and heart rate were not fluctuant. 3. The peroxidative reaction was significantly suppressedin B group. MDA level reduced and the activities of T-AOC and SODincreased. 4. C and D groups couldn't suppress the preoxidative reaction,MDA level increased all the time during surgery. 5. MDA level In A groupdecreased at first, after 2 hours it increased gradually. At the end ofoperation, there was no difference compared with that of beforeanesthesia.Conclusions:There is imbalance of peroxidation-antioxidation in breastcancer patiens. Propofol has antioxidation activity, it can suppress lipidperoxidation and can enhance the activities of SOD and T-AOC. By theway, propofol can change the imbalance status of superoxidation-antioxidation in breast cancer patients during surgery. Inhalation of lowoxygen concerntration is helpful to patients.