Hyperoxia vs Normoxia During Cardiopulmonary Bypass

Hyperoxia During Cardiopulmonary Bypass in Adult Cardiac Surgery: A Randomized Controlled Pilot Study

This single-center randomized controlled pilot trial evaluates the effects of intraoperative hyperoxia compared with normoxia during cardiopulmonary bypass (CPB) in adult patients undergoing elective cardiac surgery. The primary aim is to assess the impact on postoperative renal function. Secondary outcomes include inflammatory markers, cardiovascular and pulmonary complications, resource utilization, and short-term mortality.

This monocentric randomized controlled pilot trial enrolled adult patients undergoing elective cardiac surgery requiring CPB. Participants were randomized (1:1) to receive either normoxic (PaO₂ 70-150 mmHg) or hyperoxic (PaO₂ >300 mmHg) oxygenation strategies intraoperatively.

The study evaluates postoperative renal function using eGFR, NGAL, renal replacement therapy, and KDIGO classification. Secondary outcomes include IL-6 levels, arrhythmias, mechanical circulatory support, surgical complications, ventilation duration, ICU/hospital stay, and 28-day mortality.

Inclusion Criteria:

• adult patients (>18 years old)
• need for elective cardiac surgery requiring CPB (i.e., isolated valve repair/replacement, coronary artery bypass grafting, or ascending aorta surgery)
• Time frame from July 1st to September 15th 2025

Exclusion Criteria:

• refusal of consent,
• pregnancy,
• previous Intensive Care Unit (ICU) admission,
• history of cardiac surgery requiring CPB,
• signs of preoperative cardiogenic shock (defined as requiring inotropic support, intra-aortic balloon pump, or other mechanical circulatory assistance),
• intraoperative need for circulatory arrest.