Perioperative Anemia, Gender, Blood Transfusion and Urine Output during Cardiopulmonary Bypass: Risk Factors for Acute K. Injury

Abstract

Objective: The aim of current study was to find out the factors causing Acute Kidney Injury (AKI) in the postoperative period of cardiac surgery. This prospective study, Peri-operative Anemia, Urine Output, gender, need for Intra-operative blood transfusion were analyzed for association of AKI. Material and Method: The study was conducted at Cardiac Center, QAMC Bahawalpur from January, 2019 to June, 2021. A total of 180 patients who underwent cardiopulmonary bypass for IHD and Valve surgery were studied. CPB hemoglobin levels, Blood Transfusion in OR, Gender specificity, Peri-operative urine output (Group1 UO <4ml/kg/hr: Group 2 UO > 4ml/kg/hr) were correlated to establish their relationship in causing post-operative Acute Kidney Injury. The patients were divided into two groups one who had Acute Kidney Injury other who don’t. Results: Acute kidney injury developed in 20 out of 180 patients, current study showed insignificant relation between CPB time, X clamp time, Gender, Surgery type, MAP and Postoperative Acute Kidney Injury. Acute Kidney Injury was more associated with diabetes, need of blood transfusion, perioperative hemofiltration and reduced urine output. Conclusion: Current study showed that Acute Kidney injury is an avoidable complication if hemoglobin levels are kept above 8-9 gm/dl to ensure proper oxygen supply and need of Intraoperative hemofiltration and BT is reduced by reducing circuit length thus hemodilution and found a urine output less than 4 ml/kg/hr during cardiopulmonary bypass carries major risk for AKI. Keywords: AKI Acute Kidney injury CPB Cardiopulmonary bypass UO urine output MAP Mean Arterial Pressure

Effect of Shorter Cross Clamp Time vs. longer Cross Clamp time on cardiac enzyme levels in pts of CAD undergoing CABG

“…The cross clamp is used to temporarily stop blood flow through the aorta, the main artery that carries blood from the heart to the rest of the body, during certain cardiac procedures. Prolonged cross clamp time can result in reduced blood flow to the heart muscle, leading to ischemic injury and potential damage to the myocardium, which is the muscle tissue of the heart 21,22,23,24 . During the period of cross clamp time, the heart is deprived of oxygen and nutrients, and waste products build up in the cardiac tissue.…”

“…This can result in myocardial damage, including cell death, inflammation, and impaired cardiac function. Reperfusion injury, which occurs when the clamp is released and blood flow is restored, can also contribute to myocardial damage due to the sudden reintroduction of oxygen and other substances to the previously deprived tissue, potentially causing oxidative stress and inflammation 9,13,15,24 .…”