Effects Of General Anesthesia Combined Thoracic Epidural Block On Hemedynamics In Thoracic Operation With Arterial Pressure-based Cardiac Output System

Objective: To observe the effect of general anesthesia combined withthoracic epidural block on hemodynamics in the patients undergoingthoracic operation.Methods:Thirty adult patients undergoing thoracic surgery,wererandomlly allocated to general anesthesia group（I group） and generalanesthesia combined thoracic epidural block group（II group）.All patientsin II group were punctured successfully and epidural catheter wereremainded at T7-9. MAP, HR, SV, SVI, CO, CI, SVR and SVRI weremonitored through Flo Trac/Vigileo system before anesthesia,10min afterintubation,30min after two-lung ventilation,30min and1h after one-lungventilation, and the end of surgery,meanwhile arterial blood gas parameterswere determined, and DO₂and DO₂I were calculated. The volume of fluidinfusion in every hour, intraoperative total volume，urine and blood losswere recorded. VAS scores and the incidence rate of complication after operation were also observed.Results:1. In the two groups, MAP, HR, SV, SVI, CO, CI, SVR and SVRI10minutes after anesthesia were decreased compared with that beforeanesthesia（P<0.05）, MAP, SV, SVI, CO, CI, SVR and SVRI weredecreased after one-lung ventilation（P<0.05）. HR and MAP in group IIwere lower than that in group I（P<0.05）, and SVV were higher than that ingroup I（P<0.05）. After giving additional ropivacaine, hemodynamics weredeclined compared with that in I group（P<0.05）, and SVV wassignificantly increased. In each group, hemodynamic changes were nodifference at other time points in the two group.2. Glucose was increased at the end of surgery, meanwhile glucose ingroup II was lower than that in group I（P<0.05）. DO₂and DO₂I wasdecreased in the operation than that before anesthesia, but it was kept innormal range, there is no significant difference in the two groups. Duringone-lung ventilation, DO₂and DO₂I in group II was lower than groupI（P<0.05）.3. The amount of infusion in2nd and3rd hour and the total infusionvolume in group II were significantly greater than that in group I（P<0.05）,urine volume and blood loss were similar in the two groups. VAS scores in group II were all declined compared with that in group I at every time pointpostoperation, less patients have adverse reaction in group II.Conclusion: General anesthesia combined thoracic epidural block canmeet the needs in thoracic surgery, it can also inhibit stress responsemaintain homeostasis and oxygen delivery, provide more effective analgesiaafter operation. Hemodynamics may be fluctuated induced by generalanesthesia combined thoracic epidural block. The key of management isappropriately supply blood volume or using vasoactive drugs. FloTrac/Vigileo system can direct fluid therapy.