Intra-operative Fraction of Inspired Oxygen and Lung Injury in Coronary Artery Bypass Grafting Surgery

Intraoperative Fraction of Inspired Oxygen and Lung Injury in Coronary Artery Bypass Grafting Surgery

This study is a prospective observer blinded, central randomization controlled, multi-center clinical trial to assess the relationship between intraoperative FiO2 and postoperative pulmonary complications with lung injury.

Hyperoxia is common in cardiac surgery and is easy to prevent by adjusting FiO2. Since there is no prospective study on different FiO2 and postoperative pulmonary complications (PPCs) during cardiac surgery. We hypothesized that hyperoxia during cardiac surgery could lead to higher incidence of lung injury and PPCs than normoxia. The objective of this trial is to compare postoperative PPCs and other outcomes between hyperoxia and normoxia strategy by PaO2/FiO2 in CABG patients.

Inclusion Criteria:

• Age from 18 to 75
• BMI from 20 to 39.9
• ASA II/III
• Undergoing isolated selective on-pump CABG through median sternotomy
• Subsequent admission to an intensive care unit (ICU).

Exclusion Criteria:

• with severe chronic obstructive pulmonary disease (COPD)
• Pregnant woman.
• With current acute coronary syndrome (<1 week)
• Severe anemia (hemoglobin <10g/L)
• Preoperative supplemental oxygen requirement to maintain arterial O2 of 92%,
• Right to left shunt in heart
• Carotid stenosis defined as >50% stenosis of either carotid artery,
• Cardiac surgery that requires intraoperative circulatory arrest,
• Current use of dialysis,
• One-lung ventilation during surgery,
• Recent smoking (within 1 month),
• Non-respiratory reason to reintubate or delayed extubation such as bleeding or heart failure,
• Perioperative allogenic transfusion with red blood cell, plasma or platelet