[Effects of perfusion pressure on cerebral blood flow and oxygenation during normothermic cardiopulmonary bypass].
BACKGROUND
Central nervous system dysfunction after cardiopulmonary bypass (CPB) is an important cause of morbidity and mortality after cardiac surgery. Perfusion pressure (PP) during CPB could be one of the important determinants of cerebral blood flow (CBF). The objective of the present study was to determine the effect of PP on CBF and cerebral oxgenation during normothermic CPB.


METHODS
Twelve adult patients undergoing coronary artery bypass graft surgery were randomly assigned to one of two groups based on PP (High and Low group). Patients in High group received phenylephrine immediately after the onset of CPB to maintain PP between 60 and 80 mmHg. Oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb), tissue oxygenation index (TOI), and oxidized cytochrome aa3 (CtOx) were measured by near-infrared spectroscopy, and internal jugular venous bulb blood oxygen saturation (SjvO2) was measured simultaneously. S-100 beta protein concentrations were also measured before and after CPB.


RESULTS
SjvO2 in High group increased significantly during CPB. CtOx in Low group decreased significantly during CPB, whereas TOI was unchanged. Although S-100 beta increased significantly at the end of CPB, there was no difference between the groups.


CONCLUSIONS
These results suggest that maintaining high PP is benefical for CBF during normothermic CPB.
Department of Anesthesiology and Critical Care, Division of Clinical Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551.
Hiroshi
H
Hamada
Itsuo
I
Nakagawa
Fumihiko
F
Uesugi
Takashi
T
Kubo
Takeshi
T
Hiramatsu
Tomoko
T
Kai
Shozo
S
Hidaka
Kaoru
K
Hamaguchi
D000368:Aged; D015415:Biomarkers / Q000097:blood; D001831:Body Temperature; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D002560:Cerebrovascular Circulation; D001026:Coronary Artery Bypass; D003576:Electron Transport Complex IV / Q000097:blood; D006801:Humans; D002534:Hypoxia, Brain / Q000175:diagnosis / Q000209:etiology; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009414:Nerve Growth Factors; D010092:Oximetry; D010101:Oxygen Consumption; D010477:Perfusion / Q000009:adverse effects*; D011312:Pressure; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000097:blood*; D019265:Spectroscopy, Near-Infrared
D015415:Biomarkers; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D003576:Electron Transport Complex IV