IRCT20211101052940N1 IRCT 2022-02-05 Shahid Rajaei Cardiovascular Hospital The effect of moderate acidification of arterial blood pH by controlled inhalation of carbon dioxide on the rate of reperfusion injury in the early minutes after aortic clamp opening during heart valve surgery: A Pilot Study The effect of moderate acidification of arterial blood pH by controlled inhalation of carbon dioxide on the rate of reperfusion injury in the early minutes after aortic clamp opening during heart valve surgery: A Pilot Study 2022-02-20 anticipated 60 Complete https://irct.ir/trial/60002 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Not used, Assignment: Other, Purpose: Prevention, Randomization description: Patients are divided into two groups of 30 based on randomized block size 4. A list of how patients are crashed into a closed envelope is provided to the researcher and patients are assigned to each of the intervention and control groups before the aortic clamp is opened. Performed by the researcher, Blinding description: In this study, the intensive care unit nurse who is responsible for caring for the patient is kept blind. N/A The effect of moderate arterial blood acidosis during reperfusion in valvular heart surgery. Intervention 1: Intervention group: Temporary respiratory acidosis is induced for the reperfusion phase by intentional inhalation of Carbon dioxide gas into the oxygenator, and therapeutic hypercapnia (partial pressure of carbon dioxide = 50-60) is performed to establish a pH in the range of 7.25 to 7.30. In contrast, 6 minutes before reperfusion, gas is added to the mixture of oxygen and air, and after opening the aortic clamp, it continues for 2 minutes after reperfusion. Intervention 2: Control group: In this group of patients, reperfusion will be performed with normal pH, ie between 7.35 and 7.45. No - There is not a plan to make this available Justification or reason for not sharing IPD is Based on the consent obtained from patients, their information remains confidential.