The Clinical Research Of Goal-directed Fluid Management In Escharectomy And Skin Grafting For Severe Burn Patients

Background and Objectives:Severe burns are one of the major threats to human life across the world.In the United States,more than 450,000 people suffer from burns every year.In the world,about 180,000people die of burns every year,most of them in low-income or middle-income countries.With our limited surgical resources,to provide the best treatment for burn patients,especially severe burn patients,requires the cooperation of many disciplines.Although most severe burn patients have passed the most dangerous shock stage and entered the infection stage,their physiological condition is still unstable and they may return to the shock state at any time,which brings great challenges to fluid management during operation.The volume management of severely burned patients is a major problem that anesthesiologists are facing at home and abroad.Goal-directed fluid management?GDFM?regulates the hemodynamics and oxygen dynamics of patients in real time according to a number of hemodynamic parameters that are well correlated with volume.The ultimate goal of GDFM is to balance the supply and demand of oxygen in patients'tissues and cells,which provides effective guidance for volume management of large-scale surgery anesthesia.In addition,a series of studies using GDFM in critically ill patients have shown that this method can not only avoid excessive transfusion,but also reduce the risk of postoperative complications,infections and cardiovascular events,and shorten hospitalization time in ICU.These safety and validity evidences provide a guarantee for the use of GDFM in intraoperative volume management of severely burned patients.Therefore,we speculate that GDFM can provide more accurate fluid management for patients with severe burns.Under the condition of balanced supply and demand of perfusion and tissue cell oxygen,reducing the dosage of plasma and erythrocyte is helpful to reduce the complications after operation.Under the guidance of the concept of rapid recovery after operation and aiming at the refined liquid management of critical patients,this study formulated a specific volume management scheme for severe burn patients undergoing escharectomy and skin grafting,and compared it with the conventional volume management scheme,explored the best volume management method for severe burn patients,in order to provide reliable clinical basis for anesthesia management during escharectomy and skin grafting.Research object and Method:According to inclusion/exclusion criteria,patients admitted to Southwest Hospital Burn Research Institute from February 2017 to November 2018 who were diagnosed as severe burns(the total area of burns accounted for more than 50%of the total surface area or the area of deep second degree burns?>30%TBSA?and who underwent escharectomy and skin grafting were selected as the subjects of study.After signing the informed consent,the subjects were randomly assigned according to the 1:1 random number table method.According to the pre-experimental data,the average blood transfusion volume in the GDFM group was lower than that in the Con group,and its reduction was 462 ml.The researchers set a 450 ml reduction in blood transfusion volume as effective,the test level was?=0.05,the test efficiency was?1-??=0.8,the ratio of two groups was 1:1,and the sample content was 17 in each group.Assuming that the loss rate is 20%,the sample size was 20 persons in each group,totaling 40 persons.We enrolled 21 cases in GDFM group and 21 cases in Con group.In the GDFM group,the competent anesthesiologist managed intraoperative volume according to the goal-directed fluid management scheme,who based on the variability of stroke volume variation,stroke volume index,central venous oxygen saturation,cardiac index.In the Con group,the anesthesiologist in charge managed intraoperative volume according to clinical experience and conventional liquid management scheme,who based on central venous pressure,mean arterial pressure,urine volume.During the follow-up,the data of the two groups,whose hemodynamics and arterial and venous blood gas indexes were collected at 10min before anesthesia,1 h and 2 h after the operation,the end of the operation,and 1 h,6 h,12 h,24 h and 48 h after operation.And the indexes of heart,liver and kidney function,systemic infection,complications of cardiovascular system,respiratory system,urinary/reproductive system,blood system,endocrine system,systemic inflammatory response syndrome and the total stay time and death rate in ICU were measured at 24 h and48 h after operation.The data were processed by SPSS 22.0 and Graph Pad software.The measurement data were expressed by x±s.Thetest,independent sample t-test and ANOVA of repeated measurement data were used.The difference was statistically significant?P<0.05?.Result:1.There was no significant difference in mean arterial pressure,central venous pressure and heart rate between the two groups.Compared with pre-anesthesia,the body temperature in Con group decreased significantly at the beginning of 1 h?P<0.05?,the beginning of 2 h?P<0.01?and the end of operation?P<0.01?.The body temperature level in Con group was significantly lower than that in GDFM group at the beginning of 1 h?P<0.05?,the beginning of 2 h?P<0.01?and the end of operation?P<0.01?,and there were no significant difference between the two groups at other time points.2.Compared with Con group,the input of plasma in GDFM group was significantly lower than that in Con group?P<0.05?.There were no significant difference in the changes of red blood cells,balance fluid,saline,total intake,bleeding volume,urine volume and total output between the two groups.3.In GDFM group,1 h?P<0.01?and 12 h?P<0.05?after operation were significantly lower than those in Con group,and there was no significant difference between the two groups at other time points.There were no significant difference in GEDI,CI and SVRI between the two groups.4.The level of OI in Con group was significantly lower than that in GDFM group at 1 h after operation?P<0.01?,and there was no significant difference between the two groups at other time.Compared with pre-anesthesia,ScvO₂ level in Con group was significantly lower at 1 h after operation?P<0.05?,and that in Con group was significantly lower at 1 h and 6 h after operation than that in GDFM group?P<0.01?,and there were no significant difference between the two groups at other time.The level of Pcv-aCO₂ in Con group was significantly higher than that in GDFM group at the end of operation,1 h and 12 h after operation?P<0.05?,and there were no significant difference between the two groups at other time.5.In Con group,compared with before anesthesia,the level of Lac increased significantly at the beginning of 2 h?P<0.05?,the end of operation?P<0.05?,the 1 h after operation?P<0.01?,and the 6 h after operation?P<0.05?.In GDFM group,compared with before anesthesia,the level of Lac increased significantly at the end of anesthesia?P<0.05?and 1 h after operation?P<0.05?.There were no significant difference of Lac level between Con group and GDFM group at each time point.6.There were no significant differences in cardiac function,liver function,renal function and systemic infection between the two groups.7.There were no statistical difference in the occurrence of complications such as cardiovascular system,respiratory system,urinary/reproductive system,blood system,endocrine system and systemic inflammatory response syndrome between the two groups within 7 days after operation.8.There was no significant difference in ICU stay time between GDFM group and Con group.The death of 30 days after operation,2 patients died in the hospital and 3 patients were discharged automatically after giving up treatment in the Con group;3 patients died and 6patients were discharged automatically after giving up treatment in the GDFM group.Because of too many confounding factors,no statistical analysis was made.Conclusion:1.Implementing GDFM can provide more accurate volume management scheme for severe burn patients,which is conducive to saving blood products during operation.2.GDFM was no significant effect on hemodynamics,body acid-base status,heart,liver and kidney function and systemic infection after severe burn surgery,but its oxygenation status was improved significantly.3.GDFM was no significant effect on the complications of cardiovascular system,respiratory system,urinary/reproductive system,blood system,endocrine system and systemic inflammatory response syndrome during seven days after operation.4.GDFM was no significant effect on ICU stay time.The number of severe burn patients who abandon treatment and discharged automatically is more often.There are too many confounding factors in the mortality rate of 30 days after operation,which is not a key indicator.