Hypertension as a risk factor for cerebral injury during cardiopulmonary bypass. Protein S100B and transcranial Doppler findings

• Published in: Anaesthesia 2001-08, Vol.56 (8), p.733-738
• Main Authors: SCHMIDT, M, SCHEUNERT, T, STEINBACH, G, SCHIRMER, U, MARX, T, FREITAG, N, REINELT, H
• Format: Article
• Language: English
• Subjects: Aged; Anesthesia; Anesthesia depending on type of surgery; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Biomarkers - blood; Blood Flow Velocity - physiology; Blood Pressure - physiology; Body Temperature - physiology; Calcium-Binding Proteins - blood; Cardiac Output - physiology; Cardiopulmonary Bypass; Cerebrovascular Circulation - physiology; Contraindications; Female; Humans; Hypertension - complications; Male; Medical sciences; Middle Aged; Middle Cerebral Artery - physiology; Nerve Growth Factors - blood; Risk Factors; S100 Calcium Binding Protein beta Subunit; S100 Proteins; Stroke - physiopathology; Stroke - prevention & control; Thoracic and cardiovascular surgery. Cardiopulmonary bypass; Ultrasonography, Doppler, Transcranial - methods
• ISSN: 0003-2409; 1365-2044
• DOI: 10.1046/j.1365-2044.2001.02105.x

We studied 22 patients aged 53-78 years scheduled for cardiac surgery under cardiopulmonary bypass. Blood pressure, cardiac output, transcranial Doppler blood flow velocity, arterial blood gases, body temperature and protein S100B, as a marker for cerebral integrity, were evaluated in normotensive and hypertensive patients. Pre-operative mean (SD) arterial blood pressure was 93 (11) mmHg in the normotensive group compared with 116 (15) mmHg in the hypertensive group. We found an increase in protein S100B levels in both groups. Serum protein S100B concentrations in the hypertensive group were significantly higher than in the normotensive group (p < 0.001). The highest mean (SD) values were 2.04 (0.65) micromol x l(-1) in the normotensive group and 7.02 (4.55) micromol x l(-1) in the hypertensive group. These results suggest that cardiopulmonary bypass is associated with a significantly higher rate of cerebral injury in hypertensive patients than in normotensive patients. This may be due to altered autoregulation and insufficient cerebral perfusion. Modifications of cardiopulmonary bypass management for hypertensive patients might be made to decrease the risk of cerebral injury.