title: Comparison of capillary and arterial lactate levels in patients with shock.
abstract: OBJECTIVE
  Several guidelines recommend point-of-care lactate measurements for therapeutic decision-making in patients with shock. The aim of the study was to validate capillary lactate measurements with a bedside micromethod in patients with shock.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  Capillary lactate levels measured by a micromethod (CAPI) and arterial lactate levels measured by a standard laboratory method (ARTs) were simultaneously and repeatedly assayed in consecutive ICU patients with shock. The validity and clinical acceptability of the CAPI method was assessed from its reproducibility, the arterio-capillary lactate difference (ACLD) and conventional diagnostic indicators.
  
  
  RESULTS
  Lactate measurements were available for 139 time-points in 37 patients. CAPI values correlated well with ARTs values (intraclass coefficient correlation: r2=0.92, P<0.001). CAPI had a sensitivity of 98%, a specificity of 36%, an accuracy of 88% and a positive predictive value of 89% to detect lactate values≥2mmol/L (P<0.0001). The mean bias between the two methods (ACLD: 0.56±2.21mmol/L) was mainly due to higher lactate concentration in capillary blood.
  
  
  CONCLUSIONS
  CAPI was correctly correlated to ARTs. The bias between the two methods is probably acceptable for triage purpose. Patients with elevated capillary lactate or in shock should be monitored with atrial-based lactate.
authors.affiliation: Pôle d'anesthésie, réanimation chirurgicale, Samu-Smur, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67000 Strasbourg, France; EA 3072, institut de physiologie, fédération de médecine translationnelle de Strasbourg (FMTS), faculté de médecine de Strasbourg, 67000 Strasbourg, France. Electronic address: Olivier.collange@chru-strasbourg.fr.
authors.forename: Olivier
authors.initials: O
authors.lastname: Collange
authors.affiliation: Pôle d'anesthésie, réanimation chirurgicale, Samu-Smur, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Garcia
authors.affiliation: Département de chirurgie cardiovasculaire, hôpitaux universitaires de Strasbourg, 67000 Strasbourg, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Kindo
authors.affiliation: Département de Santé publique, groupe méthode en recherche clinique, hôpitaux universitaires de Strasbourg, 67000 Strasbourg, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Meyer
authors.affiliation: Laboratoire de biochimie et biologie moléculaire, hôpitaux universitaires de Strasbourg, 67000 Strasbourg, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lavaux
authors.affiliation: Pôle d'anesthésie, réanimation chirurgicale, Samu-Smur, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67000 Strasbourg, France; EA 3072, institut de physiologie, fédération de médecine translationnelle de Strasbourg (FMTS), faculté de médecine de Strasbourg, 67000 Strasbourg, France.
authors.forename: Paul Michel
authors.initials: PM
authors.lastname: Mertes
authors.affiliation: Department of anesthesiology and pain management, university of Texas Southwestern medical center at Dallas, Texas, USA.
authors.forename: Girish P
authors.initials: GP
authors.lastname: Joshi
authors.affiliation: Pôle d'anesthésie, réanimation chirurgicale, Samu-Smur, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Diemunsch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000378:metabolism*; D002196:Capillaries / Q000378:metabolism*; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007773:Lactates / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012769:Shock / Q000097:blood*; D014218:Triage
chemical_list: D007773:Lactates
keywords: Lactate; Point-of-care testing; Shock; Triage