title: Normothermic cardiopulmonary bypass increases cerebral tissue oxygenation during combined valve surgery: a single-centre, randomized trial.
abstract: OBJECTIVE
  In cardiac surgery, the choice of temperature regimen during cardiopulmonary bypass (CPB) remains a subject of debate. Hypothermia reduces tissue metabolic demands, but may impair the autoregulation of cerebral blood flow and contribute to neurological morbidity. The aim of this study was to evaluate the effect of two different temperature regimens during CPB on the systemic oxygen transport and the cerebral oxygenation during surgical correction of acquired heart diseases.
  
  
  METHODS
  In a prospective study, we randomized 40 adult patients with combined valvular disorders requiring surgical correction of two or more valves into two groups: (i) a normothermic (NMTH) group (n = 20), in which the body core temperature was maintained at 36.6°C during CPB and (ii) a hypothermic (HPTH) group (n = 20), in which the body was cooled to a core temperature of 32°C maintained throughout the period of CPB. The systemic oxygen transport and the cerebral oxygen saturation (SctO2) were assessed by means of a PiCCO2 haemodynamic monitor and a cerebral oximeter, respectively. All the patients received standard perioperative monitoring. We assessed haemodynamic and oxygen transport parameters, the duration of mechanical ventilation and the length of the ICU and the hospital stays.
  
  
  RESULTS
  During CPB, central venous oxygen saturation was significantly higher in the HPTH group but SctO2 was increased in the NMTH group (P < 0.05). Cardiac index, systemic oxygen delivery and consumption increased postoperatively in both groups. However, oxygen delivery and consumption were significantly higher in the NMTH group (P < 0.05). The duration of respiratory support and the length of ICU and hospital stays did not differ between the groups.
  
  
  CONCLUSIONS
  During combined valve surgery, normothermic CPB provides lower central venous oxygen saturation, but increases cerebral tissue oxygenation when compared with the hypothermic regimen.
authors: Department of Anesthesiology and Intensive Care Medicine, City Hospital #1 of Arkhangelsk, Arkhangelsk, Russian Federation.
authors: Andrey I
authors: AI
authors: Lenkin
authors: Viktor I
authors: VI
authors: Zaharov
authors: Pavel I
authors: PI
authors: Lenkin
authors: Alexey A
authors: AA
authors: Smetkin
authors: Lars J
authors: LJ
authors: Bjertnaes
authors: Mikhail Y
authors: MY
authors: Kirov
mesh_terms: D000328:Adult; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods*; D002560:Cerebrovascular Circulation; D016009:Chi-Square Distribution; D006349:Heart Valve Diseases / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006351:Heart Valves / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects; D007362:Intensive Care Units; D007902:Length of Stay; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012121:Respiration, Artificial; D012426:Russia; D019265:Spectroscopy, Near-Infrared; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010100:Oxygen