title: Clinical evaluation of time-resolved spectroscopy by measuring cerebral hemodynamics during cardiopulmonary bypass surgery.
abstract: We developed a three-wavelength time-resolved spectroscopy (TRS) system, which allows quantitative measurement of hemodynamics within relatively large living tissue. We clinically evaluated this TRS system by monitoring cerebral circulation during cardiopulmonary bypass surgery. Oxyhemoglobin, deoxyhemoglobin, total hemoglobin and oxygen saturation (SO(2)) were determined by TRS on the left forehead attached with an optode spacing of 4 cm. We also simultaneously monitored jugular venous oxygen saturation (SjvO(2)) and arterial blood hematocrit (Hct) using conventional methods. The validity and usefulness of the TRS system were assessed by comparing parameters obtained with the TRS and conventional methods. Although the changes in SO(2) were lower than those in SjvO(2), SO(2) obtained by TRS paralleled the fluctuations in SjvO(2), and a good correlation between these values was observed. The only exceptions occurred during the perfusion period. Moreover, there was a good correlation between tHb and Hct values (r(2)=0.63). We concluded that time-resolved spectroscopy reflected the conditions of cerebral hemodynamics of patients during surgical operations.
authors.affiliation: Hamamatsu Photonics K.K., Central Research Laboratory, 5000 Hirakuchi, Hamamatsu, Shizuoka, 434-8601, Japan. etuko-o@crl.hpk.co.jp
authors.forename: Etsuko
authors.initials: E
authors.lastname: Ohmae
authors.forename: Motoki
authors.initials: M
authors.lastname: Oda
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Suzuki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kakihana
authors.forename: Akira
authors.initials: A
authors.lastname: Matsunaga
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kanmura
authors.forename: Mamoru
authors.initials: M
authors.lastname: Tamura
mesh_terms: D000368:Aged; D001785:Blood Gas Monitoring, Transcutaneous / Q000379:methods / Q000706:statistics & numerical data; D002560:Cerebrovascular Circulation; D001026:Coronary Artery Bypass; D003627:Data Interpretation, Statistical; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods* / Q000706:statistics & numerical data; D010100:Oxygen / Q000097:blood; D010108:Oxyhemoglobins / Q000378:metabolism; D019265:Spectroscopy, Near-Infrared / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin; D010100:Oxygen