Pulsatile Cardiopulmonary Bypass for Acute Kidney Injury Reduction in Cardiac Surgery

Cardiac surgery is a common but high-risk procedure that often involves the use of a heart-lung machine, or cardiopulmonary bypass (CPB). This machine helps to pump blood during the operation, but it can contribute to surgical risks by causing endothelial dysfunction and acute kidney injury (AKI). This happens because the machine typically generates a non-pulsatile blood flow, which is not normal and can lead to poor oxygen delivery to tissues. This study aims to observe if using a pulsatile blood flow in the CPB machine can improve endothelial function and reduce the risk of AKI. This is important because AKI can increase the risk of death after cardiac surgery, and over 400,000 people undergo surgery with CPB each year in the United States. In this observational study, patients undergoing cardiac surgery with CPB will be watched closely. Some patients will receive pulsatile CPB, while others will receive non-pulsatile CPB. The study will then compare the percent change in the flow mediated dilation of the brachial artery after cardiac surgery between these two groups. This measurement is an indicator of endothelial function, which is the main focus of the study. The goal is to see if pulsatile CPB can improve endothelial function and potentially reduce the risk of AKI.