Cerebral near-infrared spectroscopy in adult patients after cardiac surgery is not useful for monitoring absolute values but may reflect trends in venous oxygenation under clinical conditions

Objective: Cerebral near-infrared spectroscopy (NIRS) was evaluated for use in monitoring global oxygenation in adult patients after cardiac surgery. Design: Prospective, randomized clinical monitoring study. Setting: Intensive care unit for cardiac surgery; university hospital. Participants: The study included 35 patients scheduled for cardiac surgery with insertion of a pulmonary artery catheter; patients with known cerebral-vascular perfusion disturbances were excluded. Interventions: Noninvasive cerebral NIRS oxygen saturation (rSO(2)) and conventional intensive care monitoring parameters were assessed. Measurements and Main Results: Simple regression analysis was used to assess the correlation of rSO(2) to hemodynamic parameters. There was fair-to-moderate intersubject correlation to hemoglobin concentration (r = 0.45, p < 0.0001) and mixed venous oxygen saturation (SMVO2) (r = 0.33, p < 0.0001). Sensitivity and specificity of rSO(2) to detect substantial ( A standard deviation) changes in mixed venous oxygen saturation were 94% and 81%, respectively. Conclusions: Cerebral NIRS in adult patients might not be the tool to replace mixed venous oxygen monitoring. Further work has to be done to assess its potential to reflect intraindividual trends. (c) 2007 Elsevier Inc. All rights reserved.