title: Tissue oxygenation as a target for goal-directed therapy in high-risk surgery: a pilot study.
abstract: BACKGROUND
  Tissue hypoperfusion occurs frequently during surgery and may contribute to postoperative organ dysfunction. There is a need for perioperative treatment protocols aiming at improving tissue oxygenation (StO2). We hypothesised that intra-operative optimisation of StO2 improves tissue perfusion and thus reduces postoperative complications. Furthermore, we evaluated the feasibility of the optimisation algorithm used.
  
  
  METHODS
  We randomized 50 high-risk patients, all >65 years with ASA physical status III, who underwent major abdominal surgery under standardized balanced general anesthesia combined with epidural analgesia. Throughout surgery StO2 was monitored at the thenar eminence using near-infrared spectroscopy. All patients were treated according to a standard care algorithm. In addition, patients in the intervention group were treated with dobutamine if necessary to keep or raise StO2 ≥ 80%. Data were recorded continuously and complications were recorded during hospital stay with a maximum of 28 days.
  
  
  RESULTS
  The number of complications was not significantly different between groups (11 vs 20; p = 0.23). Eleven patients in the intervention group had no complication, versus 7 in the control group. There was no significant difference between groups in length of stay in ICU or in hospital. Only ten patients in the intervention group received dobutamine. Administration of dobutamine resulted in a moderate 6 [-3 to 10] % increase of StO2. The overall protocol adherence was 94%.
  
  
  CONCLUSIONS
  No statistically significant difference in outcome was realized through intraoperative optimization of StO2 values in this pilot study. The protocol used may be considered feasible for clinical practice. Further research is obligatory to define both the optimal StO2 threshold and intervention to treat tissue hypoperfusion.
  
  
  BACKGROUND
  ClinicalTrials.gov identifier: NCT01342900. Registered 21 April 2011.
authors.affiliation: Department of Anesthesiology, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, the Netherlands.
authors.forename: Paul A
authors.initials: PA
authors.lastname: van Beest
authors.affiliation: Department of Anesthesiology, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, the Netherlands.
authors.forename: Jaap Jan
authors.initials: JJ
authors.lastname: Vos
authors.affiliation: Department of Anesthesiology, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, the Netherlands.
authors.forename: Marieke
authors.initials: M
authors.lastname: Poterman
authors.affiliation: Department of Anesthesiology, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, the Netherlands.
authors.forename: Alain F
authors.initials: AF
authors.lastname: Kalmar
authors.affiliation: Department of Anesthesiology, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, the Netherlands.
authors.forename: Thomas W L
authors.initials: TW
authors.lastname: Scheeren
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015360:Analgesia, Epidural / Q000379:methods; D000768:Anesthesia, General / Q000379:methods; D004280:Dobutamine / Q000008:administration & dosage; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D007902:Length of Stay; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D010865:Pilot Projects; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D004280:Dobutamine; D010100:Oxygen
keywords: Goal-directed therapy; High-risk surgery; Near-infrared spectroscopy; Postoperative complications; Tissue oxygenation