A Study On Pharmacokinetics And Pharmacodynamics Of Target Controlled Infusion Of Propofol In Patients With Different Degrees Of Burn

Objective: To study the pharmacokinetics and pharmacodynamics of target controlled infusion of propofol in patients with different degrees of burn by bispectral index.Methods:60 patientswith ASA Ⅱ～Ⅲ,scheduled for operation in the Second Affiliated Hospital of Kunming Medical University from October 2015 to August 2016 were selected.In group A,20 patients with scar were treated with scar excision and repair,and the other 40 cases were divided into moderate and severe groups according to the area and degree of burn, and each group had 20 cases. The radial artery catheterization was performed to monitor and collect the specimensafter the patients entered the operation room.TCI propofol 3.5ug·mL-1, after the patient’s consciousness disappeared, fentanyl 3ug·kg-1, rocuronium 0.9mg·kg-1 tracheal intubation 2 mins later.The mechanical ventilation was applied after conventional trachea cannula. The initial target concentration of remifentanil was 4ng·mL-1, Maintaining the BIS between 40～60 without inhale anesthetics.Before propofol injection (T0) ,rterial blood were collected,and1(Tt1)、2(Tt2)、5(Tt5)、10(Tt10)、15(Tt15)、20(Tt20)、30(Tt30)、40(Tt40)、50(Tt50)、60(Tt60)、90(Tt90)min,after TCI propofol,and 1(T1)、3(T3)、5(T5)、8(T8)、10(T10)、20(T20)、30(T30)min,stop TCI propofol .Cardiac output(CO),stroke volume(SV),heart rate(HR),mean arterial pressure(MAP),bispectral index(BIS)and temperature(T)were collected at different time.Determination of measured plasma concentration(Cm) of propofol by high performance liquid chromatography fluorescence(HPLC-FLD).The pharmacokinetic were calculated by DAS software.Results:1、General state of patientsThere was no significant difference between the three groups in gender, age, height,weight, BMI, duration of anesthesia, dosage of propofol, bleeding volume, infusion volume (P>0.05). The dosage of remifentanil and rocuronium in C group was significantly higher than that in group A and group B (P<0.05);Preoperative,intraoperative and postoperative plasma albumin C group was significantly lower than A,B group (P<0.05), A, B group had no significant difference (P>0.05).2.Vital signsT0、 Tt1、 Tt2、 Tt5、 Tt10、 Tt15、 Tt20、Tt30、 Tt40、 Tt50、 Tt60、 Tt90、 T、 T1、 T3、T5、T8、T10、T20、T30, CO and SV were significantly higher in C group than in A group and B group (p<0.05);Tt15、Tt20、Tt30、Tt40、Tt50、Tt60、Tt90、T、T1,MAP was significantly higher in C group than in A group and B group (P<0.05); Tt5、Tt15、Tt20、Tt30、Tt40、Tt50、Tt60、Tt90、T, HR was significantly higher in C group than in A group and B group(P<0.05);BIS,at T1、T3, was significantly higher in C group than in A group and B group (P<0.05);A and B group had no significant difference (P>0.05).3.Determination of propofol plasma concentration by HPLC-FLDThe endogenous substances in blank plasma had no interference to the determination,and the separation effect of propofol and internal standard was good. The retention time was 8.0min and 4.5min. The ratio of the peak area of propofol and internal standard was Y axis, and the plasma concentration of propofol as the X axis to establish the standard curve.The regression equation was Y= 0.000319X-0.008889 (r=0.999). Propofol has a good relationship in the range of 318.91～20410.00 ng·mL-1. The results showed that the recovery rate of propofol was 97% between day and day, and the precision and stability were <10%.4、measured plasma concentration of propofolThe Cm of three groups achieved steady state are about 2mim,Tt2、Tt5、Tt10、Tt15、Tt20、Tt30、Tt40、Tt50、Tt60, at the above time points,C group was significantly lower than that of A group and B group (P<0.05); there is no significant difference between A group and B group (P>0.05).5、Pharmacokinetic parametersV1, V2, V3, CL, K10 in C group were higher than those in A group and B group(p<0.05); there was no significant difference between A and B group (P>0.05); In other indicatorsthere was no significant difference between the A, B, C.Conclusion:1、 Severe burn patients, distribution volume and clearance increased significantly, the pharmacological effect of propofol seems to be weakened, as may be appropriate to increase the dosage to achieve the same pharmacological effect, moderate burn patients in non burn patients had little difference.2. BIS for different area of propofol combined with remifentanil in patients with burn the target controlled infusion of intravenous anesthesia can achieve individualized medication, maintain the appropriate depth of anesthesia, stable hemodynamics,reduce complications and improve the safety of anesthesia to.