title: [Changes in p50 and oxygen metabolism during mild hypothermia cardiopulmonary bypass].
abstract: OBJECTIVE
  To study the changes of p50 and oxygen metabolism during mild hypothermia cardiopulmonary bypass, arterial blood lactate(ABL) were measured, arterial and venous blood gas were analysed in 21 patients undergoing cardiac valve replacement.
  
  
  RESULTS
  p50, oxygen consumption(VO2), and oxygen extract rate(ERO2) were decreased during hypothermia and increased during rewarming, respectively (P < 0.05 or P < 0.01), while the change of SvO2 was adversed. PvO2 was decreased significantly during rewarming(P < 0.01), and ABL was continuously increased.
  
  
  CONCLUSIONS
  Both reduction in oxygen utilization during hypothermia and relative deficiency of oxygen supply during rewarming cause tissue hypoxia.
authors.affiliation: Department of Anesthesiology, Second Affiliated Hospital, Hunan Medical University, Changsha 410011.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Zhou
authors.forename: Q
authors.initials: Q
authors.lastname: Chen
mesh_terms: D000328:Adult; D001785:Blood Gas Monitoring, Transcutaneous; D002315:Cardiopulmonary Bypass; D005260:Female; D006349:Heart Valve Diseases / Q000097:blood / Q000601:surgery*; D006801:Humans; D007036:Hypothermia, Induced; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*