title: Assessment of macro- and micro-oxygenation parameters during fractional fluid infusion: A pilot study.
abstract: The main goal of this study was to assess whether maximal fluid infusion improves both oxygen delivery (DO2) and micro-circulatory parameters during hemodilution. The secondary objective was to assess the ability of baseline micro-circulatory parameters to predict oxygen consumption (VO2) response following fluid infusion.
  
  
  
  In a postoperative cardiac ICU, patients received repeated fluid infusion until stroke volume (SV) was maximized. Before and after each fluid expansion, macro- (DO2, VO2) and micro-circulatory oxygenation parameters were recorded [central venous oxygen saturation (ScVO2), blood lactate, difference in veno-arterial carbon dioxide tension (P(v-a)CO2), somatic and cerebral oxygen saturation (rSO2)]. Patients were classified as VO2-Responders or VO2-Non-Responders according to an increase in VO2above or below 15%, respectively.
  
  
  
  After maximal fluid infusion, all patients showed improved macro- and micro-circulatory oxygenation parameters, but VO2-Responders had lower values (especially for ScVO2and cerebral rSO2). Only baseline ScVO2and cerebral rSO2were useful to predict the VO2response to maximal fluid infusion (ROCAUC0.80 (95% CI: 0.54-0.95, P=0.012) and 0.83 (95% CI: 0.57-0.96, P=0.001).
  
  
  
  Maximal fluid infusion improves macro- and micro-circulatory oxygenation parameters. For VO2-Responders, only ScVO2and cerebral rSO2could serve as markers of tissue hypoxia.
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France; EA 4650, Université de Caen Normandie, Esplanade de la Paix, CS 14 032, F-14 000 Caen, France. Electronic address: fischer-mo@chu-caen.fr.
authors.forename: Marc-Olivier
authors.initials: MO
authors.lastname: Fischer
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: bonnet-v@chu-caen.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bonnet
authors.affiliation: Anesthesiology and Critical Care Department, Amiens University Hospital, Place Victor Pauchet, F-80 054 Amiens, France; INSERM ERI12, Jules Vernes University of Picardy, 12 rue des Louvels, F-80 000 Amiens, France. Electronic address: lorne.emmanuel@chu-amiens.fr.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Lorne
authors.affiliation: Division of Anaesthesia, Intensive Care, Pain and Emergency Medicine, University Hospital of Nîmes, Nîmes, France. Electronic address: jean-yves.lefrant@wanadoo.fr.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Lefrant
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: olivier.rebet@free.fr.
authors.forename: Olivier
authors.initials: O
authors.lastname: Rebet
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: benourt@gmail.com.
authors.forename: Benoît
authors.initials: B
authors.lastname: Courteille
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: charlotte.lemetayer@gmail.com.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Lemétayer
authors.affiliation: Department of Biostatistics and Clinical Research, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: parienti-jj@chu-caen.fr.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Parienti
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France. Electronic address: gerard-jl@chu-caen.fr.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Gérard
authors.affiliation: Service d'Anesthésie-Réanimation, Hôpital cardiologique Louis Pradel, Avenue du Doyen Lepine, F-69 677 Lyon, France; Faculty of Medicine, University of Lyon 1 Claude Bernard, F-69 008 Lyon, France. Electronic address: jean-luc.fellahi@chu-lyon.fr.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Fellahi
authors.affiliation: Pôle Réanimations Anesthésie SAMU/SMUR, CHU de Caen, Avenue de la Côte de Nacre, CS 30001, F-14 000 Caen, France; EA 4650, Université de Caen Normandie, Esplanade de la Paix, CS 14 032, F-14 000 Caen, France. Electronic address: hanouz-jl@chu-caen.fr.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Hanouz
mesh_terms: D000368:Aged; D019540:Area Under Curve; D013504:Cardiovascular Surgical Procedures; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D005440:Fluid Therapy; D006439:Hemodynamics; D006801:Humans; D020896:Hypovolemia / Q000628:therapy*; D008297:Male; D010100:Oxygen / Q000097:blood*; D010865:Pilot Projects; D011184:Postoperative Period; D011446:Prospective Studies
chemical_list: D010100:Oxygen
keywords: Cardiac output; Fluid loading; Oxygen consumption; Oxygen delivery