Effects Of Recruitment Strategy Added To Mechanical Ventilation Patients On Hemodynamic And Cardiopulmonary Functions Analyzed By Echocardiography:a Clinical Study

Objective To evaluate the accuracy of Changes in aortic valve velocity time integral（VTI）induced by Lung Recruitment Maneuver Predict Fluid Responsiveness in lung-protective ventilation patients.Methods 45 patients with gastrointestinal surgery,ASAⅠ-Ⅱ,aged 50 to 70 years old were enrolled in this study.All patients included in this study,LVEF were>55%and have no history of serious cardiovascular and cerebrovascular diseases.According to international experts’ guidelines and consensus,all patients underwent Lung-protective ventilation（VT 7ml/kg,PEEP 5cmH2O,FiO2 60%）after tracheal intubation under general anesthesia.After hemodynamic stability,turn the pressure limiting valve（APL）of anesthesia machine to 30cmH2O and lung recruitment maneuver were performed（RM:30cmH2O continuous positive airway pressure ventilation for 30S）.In the apical five chamber view,place the pulse doppler（PW）sampling point within 1 cm of the aortic valve,and the aortic valve velocity time integral（VTI）was recorded.VTI.MAP and HR were recorded before and after lung recruitment maneuver,and ΔVTI、ΔMAP、ΔHR were calculated.Then according to international experts’ guidelines and consensus,changing tidal volume to 9ml/kg and connecting Vigileo system,the volume expansion was carried out（0.9%normal saline 250ml was intravenously infused for 20min）and ΔSV were calculated.Patients were divided into 2 groups according to ΔSV:response group（R group,ΔSV≥15%）and non-response group（N group,ΔSV<15%）.The receiver operating characteristic curve was used to analyze the ΔVTI、ΔMAP and ΔHR,and the optimal Youden index was calculated.To evaluate the accuracy of Changes in aortic valve velocity time integral（VTI）induced by Lung Recruitment Maneuver Predict Fluid Responsiveness in lung-protective ventilation patients.Results 45 patients in our study,26 patients in R group and 19 patients in N group.During the RM process,both groups showed significant decreases in MAP and VTI.The results of receiver operating characteristic curve analysis showed that:the cut-off of value of ΔVTI in predicting fluid responsiveness in lung protective ventilation patients was 18.065%,and the area under the curve was 0.893（95%CI 0.800-0.986,P<0.05）.The sensitivity of ΔVTI in predicting fluid responsiveness in lung protective ventilation patients was 92.3%,specificity was 73.7%.The cut-off of value ofΔMAP in predicting fluid responsiveness in lung protective ventilation patients was 11.12%,and the area under the curve was 0.864（95%CI 0.762-0.967,P<0.05）.The sensitivity of ΔMAP in predicting fluid responsiveness in lung protective ventilation patients was 73.1%,specificity was 84.2%.The cut-off of value of ΔHR in predicting fluid responsiveness in lung protective ventilation patients was 1.575%,and the area under the curve was 0.596（95%CI 0.427-0.765,P>0.05）.The sensitivity of ΔHR in predicting fluid responsiveness in lung protective ventilation patients was 69.2%,specificity was 52.6%.Conclusion ΔMAP and ΔHR induced by lung recruitment maneuver can not accurately predict fluid responsiveness in lung protective ventilation patients.ΔVTI induced by lung recruitment maneuver can accurately predict fluid responsiveness in lung protective ventilation patients.When the Youden index was optimal,the cut-off of ΔVTI was 18.065%,sensitivity 92.3%,specificity 73.7%.Objective To evaluate the Effects of Lung-Recruitment strategy on pulmonary oxygenation and bi-ventricular function in patients with different volume status.Methods 60 patients with gastrointestinal surgery,ASAⅠ-Ⅱ,aged 50 to 70 years old were enrolled in this study.All patients included in this study,LVEF were>55%and have no history of serious cardiovascular and cerebrovascular diseases.According to international experts’ guidelines and consensus,all patients underwent Lung-protective ventilation（VT 7ml/kg,PEEP 5cmH2O,FiO2 60%）after tracheal intubation under general anesthesia.After hemodynamic stability,turn the pressure limiting valve（APL）of anesthesia machine to 30cmH2O and lung recruitment maneuver were performed（RM:30cmH2O continuous positive airway pressure ventilation for 30S）.The echocardiographic parameters of bi-ventricular,left ventricular global longitudinal strain（LVGLS）,right ventricular free wall longitudinal strain（RVGLS）,peak velocity of early diastolic transmitral and transtricuspid（E）,flow peak early diastolic septal mitral and tricuspid valve annulus velocity（E’）,pulmonary oxygenation index（P/F）,and pulmonary dynamic compliance（Cdyn）were measured before（T1）、immediately（T₂）and 30 minutes（T3）after RM.Then according to international experts’ guidelines and consensus,changing tidal volume to 9ml/kg and connecting Vigileo system,the volume expansion was carried out（0.9%normal saline 250ml was intravenously infused for 20min）and ΔSV were calculated.Patients were divided into 2 groups according to ΔSV:response group（R group,ΔSV≥15%）and non-response group（N group,ΔSV<15%）.To evaluate the Effects of Lung-Recruitment strategy on pulmonary oxygenation and bi-ventricular function in patients with different volume status.Results 33 patients in R group and 27 patients in N group.Compared with Pre-RM（T1）,the LVGLS,LVEF,RVGLS,TAPSE,E/E’were significantly decreased in both groups at the immediately after RM（T₂,P<0.05）,while the LVMPI、RVMPI、PaO2/FiO2 ratio and pulmonary dynamic compliance were significantly increased（P<0.05）.Compared with T₂,the LVGLS,LVEF,RVGLS,TAPSE,E/E’ were significantly increased in both groups at the 30 minutes after RM（T3,P<0.05）,while the LVMPI、RVMPI、PaO2/FiO2 ratio and pulmonary dynamic compliance were significantly decreased（P<0.05）.Compared with T1,there were no significant differences in LVGLS、LVEF、RVGLS、TAPSE and E/E’in group N at T3,but RVMPI was increased（P<0.05）and dynamic lung compliance was decreased（P<0.05）.Compared with T1,LVGLS、RVGLS、TAPSE and E/E’ in R group were significantly decreased at T3（P<0.05）,while RVMPI was increased（P<0.05）and dynamic lung compliance was decreased（P<0.05）.Compared with N group,LVGLS、RVGLS、TAPSE and E/E’in R group were significantly decreased at T₂ and T3（P<0.05）,LVMPI and RVMPI were increased,but there were no significant statistically differences in PaO2/FiO2 ratio and pulmonary dynamic compliance.Conclusion RM can optimize pulmonary oxygenation and increase pulmonary compliance in patients with Lung-protective ventilation.Meanwhile,RM will reduce the function of bi-ventricular,especially in right ventricular and when patients with low blood volume.However,the reduction of myocardial function induced by RM was reversible,30 minutes after RM,the suppression of left and right ventricular function induced by RM can return to the basic state,but the premise is that the patient does not have insufficient of volume;and at this time,the patient’s lung compliance is significantly lower than the basic state.Based on above,this study suggests that the fluid responsiveness and basic cardiac function of patients should be evaluated before the recruitment strategy is implemented to prevent irreversible damage to myocardial function.