Jugular bulb oxyhemoglobin desaturation, S100 beta, and neurologic and cognitive outcomes after coronary artery surgery

We reported that a decline in cognitive performance 3 mo after coronary art ery bypass grafting surgery is associated with palpable aortic atheroma, bu t not postoperative jugular bulb oxyhemoglobin saturation (Sjo(2)) < 50%. H owever, the effect of Sjo(2) on clinical neurologic findings is not known. S100 beta is a possible surrogate biochemical marker of brain injury, and w e report here the scored clinical neurologic findings in 98 patients from o ur previous study in relation to Sjo(2), cognitive performance, aortic athe roma, and S100 beta. Patients underwent a scored neurologic examination and cognitive assessment the day before and 3 mo after coronary artery bypass grafting surgery. Intraoperatively, intermittent blood sampling was perform ed, and postoperatively, the area under the curve describing Sjo(2) < 50% i n relation to time was calculated from continuous jugular bulb reflectance oximetry. Palpation was used to assess the ascending aorta for the presence of atheroma. The jugular bulb concentration of S100 beta was measured 6 h after completion of surgery. The neurologic score 3 mo after surgery did no t correlate with either intra- or postoperative Sjo(2) (r = 0.111, P = 0.27 8; and r = -0.074, P = 0.467, respectively). The main determinant of neurol ogic score at 3 mo was the preoperative neurologic score (r(2) = 0.63, P < 0.001), whereas palpable atheroma of the ascending aorta made a small but s ignificant contribution (r(2) = 0.034, P = 0.004). Neurologic and cognitive scores correlated before surgery (r = 0.226, P = 0.022) and at 3 me after surgery (r = 0.348, P < 0.001). A preoperative neurologic deficit of two or more had a small but significant negative effect on cognitive performance at 3 mo (standardized beta = -0.097, P = 0.018). There was a significant un ivariate correlation between S100 beta and the 3-mo neurologic score (r = - 0.232, P < 0.05), but not a multivariate correlation (beta = -0.090, P = 0. 156).