title: Relation between blood flow and tissue blood oxygenation in human fingertip skin.
abstract: BACKGROUND
  Tissue blood flow (BF) is thought to be involved in the regulation of tissue blood oxygenation (StO2). The purpose of the present study was to show the relation between BF and StO2 by measuring them simultaneously under different conditions.
  
  
  METHODS
  Twenty-one healthy subjects (age 21-30years) participated in this study. We measured BF and StO2 in a small area of skin (fingertip, palm, forearm) simultaneously using a laser Doppler flowmeter and a tissue oxygenation monitor. Three measurements were made at rest while performing mental arithmetic and during constriction of the ipsilateral upper arm.
  
  
  RESULTS
  At rest, BF and StO2 were higher in the fingertip than in the palm or forearm (p<0.01). Performing mental arithmetic produced significant decreases in BF, oxygenated hemoglobin, and StO2 in the fingertip (p<0.05). Constriction of the ipsilateral upper arm produced significant decreases in BF and StO2 (p<0.05) and an increase in oxygenated hemoglobin (p<0.05). Both procedures produced significant increases in deoxygenated hemoglobin (p<0.05), which was in antiphase to the decrease in StO2.
  
  
  CONCLUSIONS
  BF decrease produced a significantly decreased StO2 in fingertip skin. The results show that simultaneous measurement of BF and StO2 is beneficial for showing the close relation between them.
authors.affiliation: Division of Periodontology and Endodontology, Department of Oral Biology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. Electronic address: ikawa@dent.tohoku.ac.jp.
authors.forename: Motohide
authors.initials: M
authors.lastname: Ikawa
authors.affiliation: Division of Oral Diagnosis, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
authors.forename: Keishiro
authors.initials: K
authors.lastname: Karita
mesh_terms: D000328:Adult; D001132:Arm / Q000098:blood supply; D001783:Blood Flow Velocity; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006225:Hand / Q000098:blood supply; D006439:Hemodynamics; D006454:Hemoglobins / Q000737:chemistry; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008433:Mathematics; D010100:Oxygen / Q000737:chemistry; D010101:Oxygen Consumption; D012867:Skin / Q000098:blood supply* / Q000473:pathology; D013696:Temperature; D055815:Young Adult
chemical_list: D006454:Hemoglobins; C100003:deoxyhemoglobin; D010100:Oxygen
keywords: Blood flow; Human; Laser Doppler; Oxygenation; Skin