Correlation Between Monitoring Renal Hemodynamics by Esophageal Ultrasound and Acute Kidney Injury After Heart Surgery

Acute kidney injury (AKI) is a common complication of cardiac surgery, which seriously affects the postoperative complication rate and mortality of patients.Acute kidney injury occurs in 5-30% of patients after cardiac surgery, but severe acute kidney injury requiring dialysis is relatively rare.At present, the diagnosis of AKI is based on serum creatinine (Scr) or urine volume. However, the changes of serum creatinine value have hysteresis, and the increase of serum creatinine level lags behind kidney injury for 48 \~ 72 h.Some drugs can also affect creatinine levels.Urine volume is also affected by many factors.Due to the lack of sensitivity and specificity of SCr, it is very important to find and adopt new early AKI markers.Kidney is an important metabolic organ of human body. Different from cerebrovascular system, kidney lacks automatic regulation ability and is easily affected by perfusion flow.Previous experiments have shown that placing a multi-plane esophageal probe into the human stomach through the esophagus can monitor the changes of left renal blood flow before, during and after cardiovascular surgery extracorporeal circulation, and has good repeatability, which may become an effective means to monitor renal blood flow during cardiovascular surgery. In conclusion, this study intends to use esophageal ultrasound as a means to monitor renal blood flow, observe the changes of intraoperative renal hemodynamic indexes, and use KDIGO ( Kidney Disease:Improving Global Outcomes)as the standard of renal injury to explore the correlation between intraoperative hemodynamic changes and postoperative AKI, providing a new perspective for the pathophysiological study of AKI after cardiopulmonary bypass.