The Effects On Hemodynamics After Induction Of General Anesthesia Of Goal-Directed Fluid Therapy By Collapsible Index Of Inferior Vena Cava

Objective:To study the reliability of IVC-CI as an indicator of volume status and volume responsiveness under spontaneous breathing;Further more,to investigate whether the IVC-CI directed fluid therapy before intubation can reduce the incidence of hypotension after induction of general anesthesia in order to maintain perioperative circulation stability.Methods:A total of 120 patients scheduled for elective surgery under general anesthesia were enrolled in this study.120 patients were randomly divided into group C?control group?and group E?experiment group?with 60 patients in each group.Invasive blood pressure?IBP?,electrocardiogram?ECG?,saturation of pulse oximetry?SpO₂?,heart rate?HR?and bispectral index?BIS?were recored routinely.Cardiac output?CO?,cardiac index?CI?,stroke volume variation?SVV?,systemic vascular resistance?SVR?were acquired with Flotrac/Vigileo hemodynamic monitoring system.Inferior vena cava diameter was measured with ultrasound and collapsible index of inferior vena cava?IVC-CI?was calculated preoperatively.After admission,patients were given 6%hydroxyethyl starch infusion therapy with a rate of 4 mL/kg/h.Fluid therapy was based on IVC-CI in Group E.If IVC-CI?43%was detected,the rehydration rate was adjusted to 15ml/kg/h until the IVC-CI decreased below 43%.Infusion rate in Group C was maintained at 4 mL/kg/h until 10min after induction.Hypotension and hemodynamic parameters after induction were recored.SPSS 19.0was used to build a database for analyzing the patients'general information and basic indicators.Patients in each group were devided into two subgroups according to their IVC-CI after admission.Thus,they were devided into C₁?IVC-CI<43%?and C₂?IVC-CI?43%?,E₁?IVC-CI<43%?and E₂?IVC-CI?43%?.The incidence of hypotension was compared in each groups.Those influencing factors on the occurrence rate of hypotension were analyzed using Logistic regression analysis.The associations between IVC-CI and Hemodynamic indicators were analyzed using the Pearson correlation test.The ROC was used to evaluate the reliability of IVC-CI in predicting post-induction hypotension.Results:The incidence of hypotension after induction of general anesthesia:group C?43.33%?was higher than group E?15%?,P<0.05.C₂ group?63.89%?was higher than E₂ group?17.65%?,P<0.05.C₁ group?12.50%?was lower than C₂ group?63.89%?,P<0.05.there was no statistically significant difference between the group E₁?11.54%?and the group E₂?17.65%?,P>0.05.When entering the operating room,IVC-CI of the C₂ group?53.87±7.94%?and E₂ group?53.46±8.95%?were higher than the C₁group?38.42±10.17%?and E₁ group?38.70±8.30%?,P<0.05.When induction,IVC-CI of E2 group?40.67±9.50%?was lower than C2 group?53.71±9.47%?,P<0.05.However,there was no statistically significant difference between E₂ group and E₁ group when inducton,P>0.05.The ROC results showed that the AUC of IVC-CI at 43%for prediction of hypotension after induction of rehydration was 0.748,and the sensitivity and specificity were 0.657,0.847.Correlation analysis showed that IVC-CI on T₁ was negatively associated CO?r=-0.334,P=0.047?on T₁,however positively associated with SVV?r=0.412,P=0.031?on T₁₁.Logistic regression analysis showed that hypotension after induction of anesthesia was associated with HR?OR=0.360,P=0.039?and CO?OR=0.626,P=0.023?after induction,at the same time,IVC-CI?OR=3.001,P=0.017?on T₁.Conclusion:The findings of this study show that IVC-CI could serve as candidate markers for the Hemodynamic indicators of General anesthesia patients.IVC-CI directed fluid therapy before inbutation can reduce the incidence of hypotension after induction of general anesthesia.HR and CO after induction,IVC-CI before inbutation were the main influencing factors of hypotension after induction of general anesthesia.