Effect Of Intraoperative Fluid Management On Dynorphin A Expression Of Skin In Patients Undergoing Abdominal Surgery

ObjectiveTo observe the influence of fluid therapy program on circulatory function,physiological function and the effects of postoperative rehabilitation for patients.And observing the expression changes of dynorphin A in the skin before and after fluid therapy with immunohistochemical methods.Methods89 cases undergoing elective majoy intraabdominal surgery under general Anesthesia were studied.The patients were randomized into group crystalloid(n=41)and group colloid(n=48).Electrocardiogram and heart rate,mean arterial pressure,central venous pressure,pulse oxygen saturation and P_ETC0₂ were monitored with the multi-function monitor.Anesthesia was induced using intravenous midazolam,propofol,fentanyl,and vecuronium,and was maintained with a balanced technique involving infusion of propofol and remifentanil with venous pump.Neuromuscular blockade was performed with intravenous vecuronium.All patients in the study received 10ml·kg the load(Ringer)and then with 8ml·kg^-1·h^-1solution throughout the intraoperative period,whereas the crystalloid was Ringer lactate solution(LRS),and the colloid was Hydroxyethyl starch 130/0.4(Voluven).All hemodynamic changes during this period were treated pharmacologically.If SBP＜90 mmHg or＞20%below baseline,and to last＞1 min,0.1-0.3mg intravenous metaradrine were given result to SBP＞90 mmHg.In the postoperative period,the surgical staff, who were unaware of the patient's group assignment and were not part of the investigator team,guided fluid therapy.These parameters HR,SBP,DBP,MAP,CVP,SP0₂,P_ET-C0₂ were recorded respectively at the time of pre-anesthesia(T₁),induction(T₂),intubation (T₃),pre-incision(T₄),incision 30 min(T₅),incision 60 min(T₆),incision 90 min(T₇),incision 120 min(T₈),before close(T₉)and end-operation(T₁₀).Liver and renal function were tested respectively at the time of before operation,the end of operation,the first day after operation.Blood loss,urine output,and doses of drugs(fentanyl, propofol,vecuronium,remifentanil)given during the surgical procedure, the need to start vasoactive infusion and the were volume of fluid were recorded.The volumes and the kinds of fluid and the number of units of blood and blood products administered in the first 1 postoperative days were recorded.Postoperative follow-up included measurements hematocrit, potassium,sodium,chloridion concentrations,and coagulation function,renal and hepatic function indes in the first 2 postoperative days.Time to first passage of flatus and feces,feed,duration of postoperative hospital stay were also recorded.Skin specimens of 30 cases were selected,crystal group 13 cases and 17 cases of colloid group.Each patient was checked the size of 0.5cm×2cm skin at the beginning of operation and at the end of operation.Then they were fixed in formalin solution 1h and washed three times with phosphate buffer.For the later use after dehydration and paraffin-embedded.Analysis was performed using Statistical Analysis System software SPSS 13.0.All the quantitative data of the two groups were compared with one-way analysis of variance,the categorical data with chi-square test. P＜0.05 was considered to represent statistical significance.Result1.The average sex,age,weight,ASA physical status and the type of surgery between the two groups were not have significantly differences(P＞0.05). 2.The doses of every anesthesia,the volumes of blood products,the duration of surgery,the estimated blood loss and urine output were not have significantly differences between the two groups(P＞0.05).3.All patients'HR,SBP,MBP,DBP do not have significantly difference between the two groups at different stages(P＞0.05),but the CVP had increased tendency,which increased from incision 60 min(T₅) in two groups.The CVP of crystalloid group were higher than group colloid from T₁ to T₅,but then were lower from T₆ to T₁₀.4.The volumes and the kinds of fluid and the number of units of blood and blood products administered in the postoperative days were smaller in the two groups and were not have significantly differences.(P＞0.05).5.The trends of WBC count and proportion of neutronphils was similar and all are increasing after operation.There was a decline in the trend among the hematocrit,platelet,albumin and glublin count.Comparation of preoperative and postoperative had significantly differences and group comparation were not have significantly differences(P＞0.05).6.Sodium levels were lower than the trend of preoperative.But potassium levels were increasing after operation.The chlorine level was stable and there was not have significantly differences between the two groups.7.The significantly longer PT,INR and lower AT in the postoperative compared with the preoperative in all patients.The increase of FIB happened in all groups at the first postoperation day.8.The postoperative hypotension,nausea and vomiting and postoperative mortality rate were smaller in the two groups.There were no significant differences between the two groups in the time of postoperative flatus and feces,feed and duration of postoperative hospital stay.9.Skin tissue immunohistochemistry results had shown that there were large areas of dynorphin A expression before fluid therapy and maily distributed in the epifermis.And the positive area had decreased significantly after fluid therapy.Conclusion1.In patients undergoing elective majoy intraabdominal surgery, intraoperative loss blood＜500ml,given infision of load 10ml·kg(Ringer) before incision and intraoperative received 8ml·kg^-1·h^-1,colloid solution or crystalloid solution could have more stable arterial pressure.2.Intraoprative two fluid therapy had no differences on dynorphin A expression in the skin.But the dynorphin A expression in the second skin was reduced significantly comparing with the first skin.3.The changes of dynorphin A expression in the skin may have an impact on wound healing and the treatment of postoperative analgesia.