title: Regional oxygenation and systemic inflammatory response during cardiopulmonary bypass: influence of temperature and blood flow variations.
abstract: OBJECTIVE
  To evaluate the role of target temperature (28 degrees or 34 degrees C) in cardiac surgery on regional oxygenation during hypothermia and rewarming and systemic inflammatory response.
  
  
  METHODS
  Prospective, controlled, and randomized clinical study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Elderly patients (mean age 70 +/- 2 years) with acquired heart disease with an anticipated bypass time exceeding 120 minutes (n = 30).
  
  
  METHODS
  The patients were cooled to either 28 degrees C (n = 15) or 34 degrees C (n = 15). At hypothermia, bypass blood flow was reduced twice from full flow (2.4 L/min/m(2) body surface area [BSA]) to 2.0 L/min/m(2).
  
  
  RESULTS
  Hepatic and jugular venous oxygen tension and saturation were higher at 28 degrees C than at 34 degrees C. In comparison with the preoperative values, at 28 degrees C hepatic venous values were higher; whereas at 34 degrees C, they were lower. The reduction of pump blood flow during hypothermia, from 2.4 to 2.0 L/min/m(2)was accompanied by reductions of central, jugular, and hepatic oxygenation at both target temperatures. During rewarming, central and regional venous oxygenation decreased irrespective of the preceding temperature. The decrease was most pronounced in hepatic venous blood, with the lowest individual values <10%. Serum concentrations of C3a and IL-6 increased during hypothermia and increased further during rewarming irrespective of the preceding temperature.
  
  
  CONCLUSIONS
  During cardiopulmonary bypass, hypothermia at 28 degrees C increases regional and central venous oxygenation better than at 34 degrees C. In contrast, venous oxygenation decreases during rewarming irrespective of the preceding temperature. No significant difference in the systemic inflammatory response associated with target temperature was detected.
authors.affiliation: Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Göteborg, Sweden. lena.lindholm@vll.se
authors.forename: Lena
authors.initials: L
authors.lastname: Lindholm
authors.forename: Anders
authors.initials: A
authors.lastname: Bengtsson
authors.forename: Vigdis
authors.initials: V
authors.lastname: Hansdottir
authors.forename: Magnus
authors.initials: M
authors.lastname: Lundqvist
authors.forename: Lars
authors.initials: L
authors.lastname: Rosengren
authors.forename: Anders
authors.initials: A
authors.lastname: Jeppsson
mesh_terms: D000368:Aged; D002315:Cardiopulmonary Bypass; D015926:Complement C3a / Q000378:metabolism; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006331:Heart Diseases / Q000601:surgery*; D006439:Hemodynamics / Q000502:physiology; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects*; D007249:Inflammation / Q000276:immunology*; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D010100:Oxygen / Q000097:blood*; D011446:Prospective Studies; D012039:Regional Blood Flow / Q000502:physiology; D017694:Rewarming / Q000009:adverse effects*
chemical_list: D006454:Hemoglobins; D015850:Interleukin-6; D015926:Complement C3a; D010100:Oxygen