Relationship Between Afterload-related Cardiac Performance And Acute Kidney Injury In Patients With Septic Shock

BackgroundSepsis refers to the life-threatening organ dysfunction caused by the host’s abnormal re sponse to infection,and is one of the main causes of death in ICU patients.Sepsis shock is a more severe clinical manifestation of sepsis,accompanied by tissue hypoperfusion that can cause multiple organ dysfunction.The heart and kidneys being one of the most frequently affected organs in sepsis,and both often occurring in sequence or in combination.In 2010,the classification of cardiorenal syndrome(CRS)was proposed,with Type 5 of CRS being secondary cardiorenal syndrome and sep sis related cardiorenal syndrome included.This means that sepsis patients have acute renal injury while developing cardiac function damage.When sepsis patients are accompanied by cardiac and renal dysfunction,the short-term survival outcome is worse,and the organ dysfunction of surviving patients may transition to chronic,which is related to long-term adverse prognosis.Therefore,early identification of sepsis induced cardiomyopathy(SCM)and sepsis associated acute kidney injury(S-AKI)is particularly important for improving the prognosis of sepsis patients.As early as 2011,foreign scholars proposed the indicator and calculation formula of afterload-related cardiac performance(ACP)by studying the relationship between changes in systemic vascular resistance(SVR)and cardiac function.The ratio of the body’s actual cardiac output(CO)to the CO required to maintain an appropriate mean arterial pressure(MAP),which is not affected by afterload can quantitatively reflect the changes of cardiac function in sepsis.There have been a few research reports abroad and domestically,indicating that ACP is closely related to the cardiac function,severity,and prognosis of sepsis patients.Based on the mechanism of cardiac renal interaction,the relationship between ACP and S-AKI deserves further exploration.Objective:By exploring the correlation between ACP and acute kidney injury in patients with septic shock,we further clarify the diagnostic value of ACP as a predictor of high risk of AKI,in order to actively improve cardiac function,reduce the incidence of AKI,and improve patient prognosis in the early stage.Research object and method:This study adopts a retrospective analysis method to include adult septic shock patients who were adm itted to the Intensive Care Unit(ICU)of the Second Affiliated Hospital of Guangzhou Medical University from June 2016 to December 2021 and underwent PiCCO monitoring within 24 hours after admission,and early full volume resuscitation.According to previous relevant studies,SCM is defined as ACP<80%,while 60%≤ACP<80%and ACP<60%can be considered as mild and severe cardiac dysfunction,respectively.This study used smooth curve fitting to depict the relationship between ACP and S-AKI,and analyzed the independent correlation between ACP and S-AKI incidence using a multivariate logistic regression model to control confounding factors.Evaluate the effectiveness of ACP in predicting the risk of S-AKI using the receiver operating characteristic curve(ROC)and compare it with the predictive value of cardiac index(CI),cardiac Power Index(CPI),and MAP for S-AKI.Apply correlation analysis to study the correlation between ACP and traditional cardiac function indicators(CI,CPI),Multivariate analysis was conducted u sing Cox proportional risk regression to investigate the correlation between ACP and inpatient mortality in patients with septic shock.Kaplan Meier survival analysis was also used to demonstrate the survival curves of hospital mortality and 28-day mortality.Results1.A total of 160 patients with septic shock were included in this study.The median stay time in the ICU was 8(4,17)days,and the overall hospital mortality rate was 59.4%;The highest proportion of patients with lung infections(36.3%),with over one-third(37.5%)of patients being diagnosed with non-drug-resistant bacterial infections;when entering the ICU,the overall patient’s creatinine level was high,with 69.4%of patients experiencing AKI and 49.4%receiving continuous renal replacement therapy.In the overall population of this study,the incidence of CRS was 54.4%.After grouping according to the patient’s cardiac function,the incidence of AKI was 41.4%in the group with normal cardiac function and 85.3%in the group with decreased cardiac function.2.The ACP of AKI group patients was lower than that of non-AKI group patients(86.16%±12.27%vs 69.93%±1.3.71%,p<0.001).Smooth curve fitting revealed a negative linear relationship between ACP and S-AKI(p=0.482).Similarly,multivariate logistic regression showed a negative correlation between ACP and the incidence of AKI(OR=0.919,95%CI 0.879-0.960,p<0.001),indicating that as ACP increased,the incidence of S-AKI decreased.3.From the ROC curve,it can be,seen that ACP can effectively predict the occurrence of S-AKI(AUC=0.819,95%CI 0.751-0.875,p<0.001).The optimal diagnostic value of ACP is 79%,sensitivity is 76.58%,and specificity is 73.47%.In addition,through ROC comparison,it was found that ACP is superior to CI and MAP in predicting S-AKI,with higher specificity than CPI.Correlation analysis showed that ACP was positively correlated with CI and CPI,with Pearson correlation coefficients r of 0.524 and 0.816,respectively,p<0.001.4.Through Cox regression analysis,it was found that there is an independent correlation between ACP and inpatient mortality in patients with septic shock(HR=0.982,95%CI:0.965-0.999,p=0.036).The K-M survival curve shows that patients with severe cardiac dysfunction have a higher 28-day mortality risk(p=0.003)compared to patients with normal cardiac function.Conclusions1.There is an independent negative correlation between ACP and the incidence of S-AKI,that is,the incidence of S-AKI decreases with the increase of ACP.2.ACP has a good predictive value for acute kidney injury in patients with septic shock,significantly superior to CI and MAP.3.Septic shock patients with severe cardiac dysfunction have a higher risk of hospitalization and 28-day death.