Cerebral Oxygenation-Guided Indexed-Flow Normothermic Cardiopulmonary Bypass with Vasopressor-Sparing Pressure Management: A Retrospective Descriptive Cohort Study

ABSTRACT Context: Mean arterial pressure targets during cardiopulmonary bypass remain debated; vasopressor-driven pressure augmentation may not improve oxygen delivery.

Aims

The aim of the paper is to describe clinical outcomes and physiologic markers during normothermic cardiopulmonary bypass managed with indexed flow, cerebral oximetry, calculated indexed oxygen delivery (DO 2 i), and vasopressor-sparing pressure management. Settings and Design: Single-center retrospective descriptive cohort study at a cardiac surgery center. Material and Methods: Consecutive adults undergoing elective or urgent cardiac surgery with normothermic cardiopulmonary bypass from June 2023 to December 2025 were included if complete anesthesia–perfusion, regional cerebral oxygen saturation (rSO 2 ), circuit-derived venous oxygen saturation (SvO 2 ), DO 2 i, and early outcome data were available. Circulatory arrest was excluded. Indexed pump flow was 2.2–2.4 L/min/m². Mean arterial pressure was interpreted with indexed flow, rSO 2 , SvO 2 , DO 2 i, hemoglobin, acid–base status, venous return, and surgical context. Baseline rSO 2 was recorded before ventilation on room air; maximal relative decrease during bypass was recorded. Statistical Analysis Used: Descriptive statistics and Wilson 95% confidence intervals were used. No comparative testing or causal modeling was performed.