The Effect Of Preoperative Intravenous Ketamine Combined With Dexamethasone On Lung Protection Undergoing Esophageal Surgery In The Process Of One Lung Ventilation

Objective: To observe the effect of preoperative intravenous ketamine combined with dexamethasone undergoing esophageal cancer radical in the process of one-lung ventilation(OLV),observe the changes of hemodynamic,blood gas analysis and inflammation mediators, and evaluate its protective function on lung, and provide theoretical reference for clinical medication. Methods: 60 cases of esophageal cancer patients undergoing thoracic surgery aged 40 to 70 years old, ASAI- II grade, were randomly divided into four groups: blank control group(group S), ketamine group(group K), dexamethasone group(group D)and ketamine plus dexamethasone group(group KD),15 cases in each group. After entering operation room,monitor the multifunctional vital signs including electrocardiogram(ECG), noninvasive blood pressure, heart rate(HR), blood oxygen saturation(SPO2), monitor invasive arterial blood pressure by radial artery catheter, epidural puncture in4-5 or 5-6 intervertebral disc and set the catheter, connect the epidural analgesia pump as anesthesia effect is definite,pharmaceutical formulation of ropivacaine1.5 mg/ml + sufentanil 0.5 ug/ml + ondansetron 4 mg with total dosage of 200 ml, start the analgesia pump and set the speed4 ml/h, Pressing amounte of thePCA is 2 ml, locking time is 15 min.Connect and monitor the Bispectral index(BIS)value.Administrate the drugs configured 15 minutes before anesthesia induction.After anesthesia induction,finish the double lumen tube intubation, link the anesthesia machine for mechanical ventilation and set the parameters :double lung ventilation(VT)8-10ml/kg, frequency of 10 to 12times/min, the oxygen concentration 50%;One-lung ventilation VT5-7 ml/kg,frequency 12-16 times/min, give the Positive end-expiratory pressure(PEEP) 5cmH2 o, oxygen concentration 100%, oxygen flow rate 1-2 litre/min, maintain the end tidal pressure of carbon dioxide(PETCO2) in 35-45 mmHg.Intravenous maintenance anesthesia with propofol 4 to 8 mg/Kg/ h and sufentanil 0.15 to 0.3ug/kg /h by micro pump, adjust anesthesia depth according to the value of brain double-frequency index(BIS), maintain the BIS value between 40 and 55,control heart rate and blood pressure within the scope of the basic value plus or minus 20%, continuously intravenous inject cisatracurium besylate,intraoperative keep intake and output fluid volume of balance.Record the hemodynamic indexes with preoperative 30 min(T0), 60 min after OLV(T1),120 min after OLV(T2), 2 hours after restoring double lung ventilation(T3)of average arterial pressure(MAP), heart rate(HR) in four groups.Draw blood from peripheral arterial blood for arterial blood gas analysis getting the value of respiratory index(RI)and blood sugar levels.Respectively detect the concentration of interleukin- 6, interleukin- 8,tumor necrosis factor-a at T0, T1,T2, T3 point in four groups by enzyme-linked immunosorbent(Elisa).Observedthe scores of postoperative analgesia in 48 hours, the total and the effective number of pressing PCEA pump,the total dosage of analgesic,postoperative nausea and vomiting, and Postoperative delirium, nightmares, hallucinations,and other adverse reactions.Results: There are no significant differences in the value of blood pressure,heart rate and SPO2 among the four groups(P>0.05).Compared with Respiratory index at T0,the value of RI increased at T1,T2,T3 time points in four groups; compared with KD group, RI values were higher with statistical significance at T2,T3 time points in group K,group D and group S(P<0.05);no significant difference is found among group D,group S and group K(P>0.05).Compared at T0,serum concentration of IL-6,IL-8 are increased at T1,T2,T3 time points in four groups,with statistical significance(P<0.05);at time T1, T2, T3, compared with group S, serum concentration of IL-6, IL-8 were significantly lower in group D,group K and group KD(P<0.05);Compared with group KD, at the time of T2, T3, serum IL-6,IL-8 concentrationsare higher than in group D, group K,the difference was statistically significant(P<0.05);there is no statistical difference between group D and group K(P>0.05); serum TNF-α concentration is lower than the minimum detectable concentration in four Groups.Postoperative VAS scores and Prince-Henry scores were markedly lower in group KD compared with group K, group D and group S in 48 hours(P< 0.05);group S,group D and group K have no statistical difference(P>0.05). The total number of pressing PCEA pump was obviously smaller in Group KD than that in group S, group K andgroup D(P<0.05).Compared with T0, four groups of blood glucose levels in T1,T2 and T3 time points were significantly increased(P<0.05);Compared with group S and group K,blood glucose significantly increased in group D and group KD at T1, T2 time points(P<0.05), while at T3 time points there are no significant differences in group K and group S(P>0.05).Postoperative nausea and vomiting were lower in group KD than that in group S,group D and group K(P<0.05).There are no statistical differences in the incidence of postoperative delirium of four groups(P>0.05).Conclusion:Ketaminecombined with dexamethasone used preoperativecan reduce intraoperative inflammatory mediators, decrease the value of respiratory index(RI), improve postoperative PCEA analgesia and reduce the incidence of postoperative adverse reactions,that can play a certain protective effect on the lung injury.