title: Performance evaluation of a new pulse oximeter during mild hypothermic cardiopulmonary bypass.
abstract: Newly developed pulse oximeters (POs) are designed to display accurate SpO(2) during motion and hypoperfusion. We compared the performance of a new PO, the Masimo SET Radical (M), with a conventional PO, the Nihon Kohden AY-900P (N), during hypothermic cardiopulmonary bypass. Eighteen patients were studied prospectively. PO failure was defined as failure to show no SpO(2) value or show incorrect SpO(2) values for longer than 3 min continuously. PO failure occurred in 4 and 14 patients with M and N, respectively (P = 0.0022). All 4 patients in whom PO failure developed with M were among the 14 patients with N. No SpO(2) was provided for 4% +/- 12% of the duration of aorta cross-clamping with M and 36% +/- 39% with N (P = 0.002). Skin temperature and mean arterial blood pressure when PO failure started to occur and ended were similar between M and N. PO failure easily developed in patients with preoperative diuretic therapy or with intraoperative hyperlactatemia in N, but not in M. M was able to display accurate SpO(2) values significantly more frequently and longer than N during mild hypothermic cardiopulmonary bypass with nonpulsatile flow, suggesting that M is more useful for monitoring SpO(2) during hypoperfusion.
  
  
  CONCLUSIONS
  We compared the performance of a new pulse oximeter with that of a conventional pulse oximeter during hypothermic cardiopulmonary bypass with nonpulsatile flow. The newly developed device displayed accurate SpO(2) significantly more frequently and longer than a conventional oximeter. Newly developed pulse oximeters seem to be more useful for monitoring SpO(2) during hypoperfusion.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. irita@kuaccm.med.kyushu-u.ac.jp
authors.forename: Kazuo
authors.initials: K
authors.lastname: Irita
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kai
authors.forename: Kozaburo
authors.initials: K
authors.lastname: Akiyoshi
authors.forename: Yukako
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Shosuke
authors.initials: S
authors.lastname: Takahashi
mesh_terms: D000368:Aged; D001011:Aorta / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D001831:Body Temperature / Q000502:physiology; D002315:Cardiopulmonary Bypass / Q000379:methods*; D003250:Constriction; D004868:Equipment Failure; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood; D011446:Prospective Studies
chemical_list: D010100:Oxygen