The Pharmacokinetics Of Rocuronium Bromide In Patients With Different Degrees Of Burn Injury

Objective:To investigate the pharmacokinetics of rocuronium bromide in burn crowd of different degrees by measuring the concentration of rocuronium in plasma of burn patients.Methods:45 patients underwent elective surgery with ASA graded ??? in the Department of Burns,Second Affiliated Hospital of Kunming Medical University from June 2018 to November 2018 were selected.They were divided into burn cicatrice group(group A)as control group included 15 patients who were going to take scar removal and skin graft repair surgery,15 cases in the moderate burn group(group B)and the other 15 cases in the severe burn group(group C).The patients was routinely monitored for vital signs after entering the operating room,and the radial artery catheterization was performed under local anesthesia.Forty-five patients were treated with target-controlled infusion of sufentanil 0.4ug/ml and dexmedetomidine 0.4 ug/kg/h for continuous intravenous pumping,induced with intravenous infection of etomidate 0.4ug/kg and rocuronium 0.9mg/kg reached an effective analgesic concentration of 0.35ug/ml,underwent tracheal intubation and mechanical ventilation after induction,set the tidal volume to 8-10ml/kg and respiratory rate to 10-12times/minute,maintaining Sp02 within 98%-100%,PetC02 within 35-45mmHg.Anesthesia maintenance:Sufentanil sustained 0.4ug/ml target-controlled infusion rate analgesia,dexmedetomidine 0.4 ug/kg/h combined with sevoflurane for sedation.During the surgery the concentration of sevoflurane would be adjusted to ensure that BIS value was between 40-60.Selecting different time points:before anesthesia(T0),after induction 1(T1),3(T3),5(T5),10(T10),15(T15),20(T20),30(T30),40(T40),50(T50),60(T60),90(T90)minutes,the time to the end of TCI(T)and 1(T1a),3(T3a),5(T5a),8(T8a),10(T10a),20(T20a)minutes after withdrawal to record vital signs,including heart rate(HR),cardiac output(CO),stroke volume(SV),mean arterial pressure(MAP),bispectral index(BIS)and temperature(T).Arterial blood samples at various time points were collected to determine the plasma concentration of rocuronium(Cm)and based on that to calculate the rocuronium's pharmacokinetic parameters.Results:1?Basic informationThere were no significant differences in gender,age,height,weight,BMI,intraoperative infusion volume,urine volume,rocuronium use,anesthesia maintenance time,and postoperative extubation time between the three groups(P>0.05).The preoperative albumin content was significantly lower in group C than in group A,group B(P<0.05),and the difference between group A and group B was not significant(P>0.05).As to preoperative alanine aminotransferase and creatinine levels in groups A,B and C,there was no significant difference(P>0.05).The blood loss was higher in group C than in group A an group B(P<0.05).2?Vital signs HR,CO,SV,MAP,BIS,TThe HR,CO and MAP values were significantly different when group C was compared with group A and B at TO,T1,T3,T5,T10,T15,T20,T30,T40,T50,T60,T90 and T,T1a,T3a,T5a,T8a,T10a,T20a each time points(P<0.05),which value was higher than group A and B.The difference of SV value between three groups was statistically significant at T60 in group C(P<0.05),which was higher than group A and B.The BIS value in group A was greater than group B at T1 and T5 time points(P<0.05),and the difference between group B and C was statistically significant at T40 time point(P<0.05),that group B was greater than group C.3?Plasma concentrations of rocuronium bromideThe plasma concentration in group C was statistically different between group A and B at T3,T5,T10,T15,T20,T30,T40,T50,T60,T90 time points for group C was lower than group A and B(P<0.05).At T1 time point there was a statistically significant difference between group C and group A that group C was lower than group A(P<0.05).4?Pharmacokinetic parameters of rocuronium bromideThe value of V1?Vd and CL of group C were larger than those of group A and group B(P<0.05).While the value of T1/2??K10 and MRT of group C were lower than those of group A and group B(P<0.05).There was no statistically significant difference in the remaining indicators of the three groups.5?There were no advert events of autonomous body movements in the three groups during the operation.All patients regained spontaneous breathing within 30 minutes after surgery,recovered call response and commanded movement.The tracheal tube of patient was removed successfully.Conclusion:1?The central volume?apparent distribution volume drug clearance in the severely burned group increased after using rocuronium bromide,meanwhile its drug elimination phase half-life was shortened,apparent first order rate constant eliminated from the central chamber decreased,mean residence time reduced,and the blood concentration of rocuronium bromide became lower.In clinical application,appropriate muscle relaxation conditions can be maintained by increasing the dosage or shortening the interval between administration.2?The muscle relaxant effect after the application of 3 times ED95 amount of rocuronium bromide in burn patients was well,and there was no excessive block of muscle relaxant.