title: The relationship between hyperlactatemia and microcirculation in the thenar eminence as measured using near-infrared spectroscopy in patients with sepsis.
abstract: OBJECTIVE
  Near-infrared spectroscopy (NIRS)-derived variables during a vascular occlusion test (VOT) have recently been used to evaluate peripheral circulatory insufficiency in patients with sepsis. We investigated the relationship between NIRS-derived variables and the lactate concentration during sepsis.
  
  
  METHODS
  This was a prospective observational study. Forty-one patients with sepsis were divided into two groups according to their blood lactate concentration: a high lactate group (≥2.0 mmol/l; n=15) and a normal lactate group (<2.0 mmol/l; n=26). NIRS was used to evaluate the tissue oxygen index (TOI) at the thenar eminence before and after a VOT. VOT was performed by sphygmomanometer cuff inflation around upper arm for 3 min. The TOI value before VOT was defined as the TOI baseline, the TOI value immediately after VOT was defined as the minimum TOI and the TOI value after releasing the muscle from the VOT was defined as the TOI after VOT. The ΔTOI was defined as the difference between the TOI after VOT and minimum TOI.
  
  
  RESULTS
  NIRS-derived variables had significant differences between the normal lactate group and the high lactate group with respect to the TOI baseline (median: 65% vs 55%, p=0.01), TOI after VOT (median: 65% vs 46%, p<0.001) and ΔTOI (median: 19% vs 6%, p<0.001). The lactate concentration was significantly correlated with the TOI after VOT (R=0.594, p<0.001), TOI baseline (R=0.513, p<0.001), ΔTOI (R=0.488, p=0.001) and minimum TOI (R=0.377, p=0.02).
  
  
  CONCLUSIONS
  We revealed a significant correlation between NIRS-derived variables and the lactate concentration during sepsis.
authors.affiliation: Department of Emergency and Critical Care Medicine, Surugadai Nihon University Hospital, Tokyo, Japan.
authors.forename: Taketomo
authors.initials: T
authors.lastname: Soga
authors.affiliation: Department of Electrical and Electronics Engineering, Nihon University College of Engineering, Koriyama, Japan Department of Neurological Surgery, Nihon School of Medicine, Tokyo, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakatani
authors.affiliation: Department of Emergency and Critical Care Medicine, Surugadai Nihon University Hospital, Tokyo, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Yagi
authors.affiliation: Department of Emergency and Critical Care Medicine, Surugadai Nihon University Hospital, Tokyo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kawamorita
authors.affiliation: Department of Neurological Surgery, Nihon School of Medicine, Tokyo, Japan.
authors.forename: Atsuo
authors.initials: A
authors.lastname: Yoshino
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006225:Hand / Q000098:blood supply*; D006801:Humans; D065906:Hyperlactatemia / Q000503:physiopathology*; D007773:Lactates / Q000097:blood; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply; D010101:Oxygen Consumption / Q000502:physiology; D011446:Prospective Studies; D018805:Sepsis / Q000503:physiopathology*; D019265:Spectroscopy, Near-Infrared
chemical_list: D007773:Lactates
keywords: intensive care