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

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.

Study Overview

• Status: Unknown
• Conditions: Postoperative Acute Kidney Injury

Detailed Description

The mechanism of acute kidney injury after CPB has not been fully elucidated, and current studies suggest that the main mechanisms are as follows:

(1) endogenous/exogenous nephrotoxic substances;(2) metabolic factors: mainly reflected in the preoperative status of patients, such as obesity, low body weight, etc.;(3) hemodynamic factors: hemodynamic instability is an important mechanism for further renal injury process such as ischemia reperfusion, which is mainly reflected in: a.preoperative and postoperative hypotension: cardiogenic shock caused by cardiac insufficiency and low cardiac displacement;Non-cardiogenic shock (vasoactive drugs/allergies/postoperative bleeding);b. hemodynamic instability of intraoperative intervention: deep anesthesia, intraoperative blood loss, CPB-related intraoperative low perfusion (long CPB time, low circulation flow, low mean arterial pressure in CPB), embolic release (atherosclerotic emboli/air emboli), aorta and distal arteriotomy;(4) neurohumoral system factors: hormones such as epinephrine, norepinephrine, renin and thyroxine change to varying degrees during cardiac surgery and CPB, thus affecting the body state and systemic blood vessels;(5) inflammation and oxidative stress.

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.For patients at high risk of postoperative acute kidney injury, appropriate intraoperative perfusion may reduce the incidence of postoperative acute kidney injury.

Esophageal ultrasound was used as a means of monitoring renal blood flow to observe the changes in intraoperative renal hemodynamic indexes. Meanwhile, KDIGO was used as the standard for renal injury. AKI was divided into two groups according to whether postoperative AKI occurred, and the correlation between intraoperative hemodynamic changes and postoperative AKI in the two groups was discussed.It provides new ideas for the early diagnosis of postoperative acute kidney injury.

• Study Type: Observational
• Enrollment (Anticipated): 60

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

60 patients undergoing elective cardiac surgery in the Affiliated Hospital of Xuzhou Medical University.

Description

Inclusion Criteria:

• Aged between 18 and 70;
• Elective cardiopulmonary bypass for patients undergoing cardiac surgery

Exclusion Criteria:

• Acute myocardial infarction surgery within 7 days
• Emergency surgery
• Known renal artery stenosis, renal malformation;Renal failure
• Congenital esophageal malformation
• Patients with previous history of stomach and esophagus should avoid intraoperative esophageal ultrasound examination
• Existing acute kidney injury, kidney transplantation, chronic kidney disease and glomerular filtration rate less than 30 ml/min,
• Pregnancy

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
AUC(RI)	ROC curve（receiver operating characteristic curve）will be drawn according to the incidence of renal resistance index (RI) monitored by TEE and the incidence of postoperative AKI in patients, and AUC value(Area Under Curve) will be statistically analyzed.	RI monitored 30 minutes after cardiopulmonary bypass termination
AUC(PI)	ROC curve will be drawn according to the incidence of renal pulsatility index (PI) monitored by TEE and the incidence of postoperative AKI in patients, and AUC value will be statistically analyzed.	PI monitored 30 minutes after cardiopulmonary bypass termination

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in biomarkers	Analysis of insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) concentrations (both induction factors for G1 cell cycle arrest are associated with acute kidney injury and are predicted as biomarkers).	Before surgery and at 4 hours, 12 hours, and 24 hours after surgery
Length of ICU stay	All patients are routinely transferred to ICU after surgery	an average of 2 days
Length of hospital stay	All patients are routinely transferred to ICU after surgery	an average of 10 days
Use of renal replacement therapy	The use of postoperative renal replacement therapy depends on the diagnosis and treatment of ICU staff.	Until 3 months after discharge
Survival rate	Record the survival rate after hospital discharged.	At 1, 7 and 30 days after discharge

Collaborators and Investigators

• Sponsor: Xuzhou Medical University
• Investigators: Study Director: Jin Dong Liu, M.S, The Affiliated Hospital of Xuzhou Medical University

Publications and helpful links

General Publications

• Weisse AB. Cardiac surgery: a century of progress. Tex Heart Inst J. 2011;38(5):486-90.
• Wang Y, Bellomo R. Cardiac surgery-associated acute kidney injury: risk factors, pathophysiology and treatment. Nat Rev Nephrol. 2017 Nov;13(11):697-711. doi: 10.1038/nrneph.2017.119. Epub 2017 Sep 4.
• Bellos I, Pergialiotis V, Kontzoglou K. Renal resistive index as predictor of acute kidney injury after major surgery: A systematic review and meta-analysis. J Crit Care. 2019 Apr;50:36-43. doi: 10.1016/j.jcrc.2018.11.001. Epub 2018 Nov 15.
• Regolisti G, Maggiore U, Cademartiri C, Belli L, Gherli T, Cabassi A, Morabito S, Castellano G, Gesualdo L, Fiaccadori E. Renal resistive index by transesophageal and transparietal echo-doppler imaging for the prediction of acute kidney injury in patients undergoing major heart surgery. J Nephrol. 2017 Apr;30(2):243-253. doi: 10.1007/s40620-016-0289-2. Epub 2016 Mar 19.

Study record dates

Study Major Dates

• Study Start (Anticipated): January 2, 2019
• Primary Completion (Anticipated): August 30, 2019
• Study Completion (Anticipated): September 30, 2019

Study Registration Dates

• First Submitted: January 1, 2019
• First Submitted That Met QC Criteria: January 4, 2019
• First Posted (Actual): January 9, 2019

Study Record Updates

• Last Update Posted (Actual): January 9, 2019
• Last Update Submitted That Met QC Criteria: January 4, 2019
• Last Verified: December 1, 2018

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Renal Insufficiency; Wounds and Injuries; Acute Kidney Injury
• Other Study ID Numbers: XYFY-2018-0008

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Individual Participant Data(IPD) will be available when this trial is finished and the article have been published.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No