Cardiopulmonary Bypass Mean Global Oxygen Delivery May Be Associated with Neurocognitive Preservation during...

The purpose of this retrospective research was to investigate the relationship between mean global oxygen delivery (DO₂) and neurocognitive function in adult patients who presented for aortic surgery with deep hypothermic circulatory arrest using cardiopulmonary bypass (CPB). From a pool of 132 patients, data from 100 CPB patients from 2012 to 2014 aged 50 years or older were randomly selected and analyzed, and global DO₂ on CPB was used to categorize patients into those for whom the mean indexed cerebral oxygen delivery (DO₂i) was either ≥272 mL O₂/min/m² (critical DO₂ [DO_2crit]) or less than DO_2crit. Ten patients experienced either stroke or expired in the perioperative course. The proportion of patients with evidence of neurocognitive preservation was 98.3% in the group in which the DO_2crit was met, compared with 80.6% in the group where DO_2crit was not met (X [1, 100] = 3.27, p = .07). Potentially, because of causes other than DO₂, the subset of patients with stroke and/or death were removed, and data from 90 cases were analyzed, and a global mean DO₂i value of 239.9 mL O₂/min/m² was identified. A larger sample size with controls may yield deeper insights into the hypothesis that a mean global CPB DO₂i of 239.9 mL O₂/min/m² may play a role in predicting neurocognitive preservation in this patient population.