The Value Of Dynamic Arterial Elastance (Eadyn) In Predicting Blood Pressure Changes In Patients With Septic Shock After Volume Expansion And Norepinephrine Dosage Reduction

Objective: Previous studies had shown that dynamic arterial elastance(Eadyn)can predict blood pressure changes in patients with shock after volume expansion and norepinephrine dosage reduction.Existing studies had Eadyn obtained from a separate signals,resulting in inaccurate results,and previous studies have not point out the value of application in patients with septic shock.The purpose of this study was to explore the value of Eadyn prediction of blood pressure changes in patients with septic shock,as Stroke volume variation(SVV)measured by the color Doppler ultrasound and pulse pressure variation(PPV)measured by the pulse pressure waveform analysis of radial artery.Methods: A prospective analysis of 2018.6-2019.8 patients admitted to the ICU of the Affiliated Hospital of Qingdao University was performed in 36 patients with septic shock.Eadyn-related indicators were obtained by two independent signals,namely SVV by the color Doppler ultrasound,and PPV by the pulse pressure waveform analysis of radial artery,Eadvn was defined as the ratio of PPV to SVV.According to the Mean arterial pressure(MAP)changes after volume expansion and norepinephrine(NE)dosage reduction,patients were divided into MAP responsive group(MAP change ≥10%)and MAP nonresponsive group(MAP change <10%)to evaluate the influencing factors of MAP changes.ROC was plotted to assess the value of Eadyn in predicting MAP response after volume expansion and norepinephrine dosage reduction.Results: 1.After VE of 36 patients with septic shock,there were 24 patients in the MAP responsive group(66.7%)and 12 patients in the MAP non-responsive group(33.3%).The baseline Eadyn in the MAP responsive group was higher than that in the MAP nonresponsive group(0.93 ± 0.09 vs.0.72 ± 0.08,t = 6.931,P<0.001).Eadyn was an effective predictor of MAP changes after volume expansion in patients with volume loading septic shock,t=7.160,P<0.001.The area under the ROC curve was 0.96 for the prediction of volume loading on MAP for Eadyn at baseline(P< 0.001).The baseline Eadyn value ≥0.79 predicted an increase ≥10% in MAP after VE with a sensitivity of 91.67% and a specificity of 95.83%.2.In 36 patients with septic shock,there were 16 patients(44.4%)in the MAP responsive group and 20 patients(55.6%)in the MAP non-responsive group.Eadyn in the non-responding group was higher than the responding group before norepinephrine dosage reduction.(1.01 ± 0.15 vs.0.83 ± 0.09,t = 4.265,P<0.001).Eadyn was an effective predictor of MAP changes after norepinephrine dosage reduction in patients with septic shock,t=-2.974,P=0.005.Eadyn≤0.91 predicted a decrease of MAP when decreasing NE dose,with an area under the ROC curve of 0.895.The sensitivity was 95%and specificity was 75%.Conclusion: The MAP changes of patients with septic shock after the volume expansion and norepinephrine dosage reduction can be predicted by using Eadyn calculated by SVV measured by the color Doppler ultrasound and PPV measured by the pulse pressure waveform analysis of radial artery.This might help clinicians make decisions about volume expansion and norepinephrine dosage reduction.In the early stage of shock when Eadyn <0.79,the norepinephrine booster drug was applied as soon as possible to improve the arterial pressure of patients.In the shock recovery period,when Eadyn > 0.91,we might try to gradually reduce the dosage of norepinephrine in order to reduce the application of vasoactive drugs.