title: Oxygenation and blood volume changes in flaps according to near-infrared spectrophotometry.
abstract: OBJECTIVE
  To test the ability of near-infrared spectrophotometry (NIRS) to predict vascular compromise in flaps postoperatively.
  
  
  METHODS
  Pilot study.
  
  
  METHODS
  Eleven denervated latissimus dorsi flaps were assessed in 8 pigs.
  
  
  METHODS
  Flaps were isolated on their vascular pedicle. We used NIRS to demonstrate tissue oxygen saturation and quantities of deoxygenated hemoglobin and oxygenated hemoglobin when flaps underwent venous or arterial occlusions. Oxygen saturation (percentage of oxygenated hemoglobin) was calculated as the difference between the 2 light intensities (860-750 nm) with the use of 2 time periods: preoperative (80%) oxygen saturation and during arterial occlusion (0%) oxygen saturation with NIRS. Blood volume changes within the flap were also measured.
  
  
  RESULTS
  Arterial occlusion resulted in significant decreases in oxygen saturation and in blood volume with immediate recovery. Venous occlusion resulted in an initial rapid increase in blood volume with no appreciable early deoxygenation.
  
  
  CONCLUSIONS
  Near-infrared spectrophotometry appears promising as a noninvasive, low-cost, portable bedside monitor that can demonstrate in real time changes in blood volume and oxygen saturation within a flap at a variety of tissue depths.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania School of Medicine, Philadelphia, USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Hayden
authors.forename: M A
authors.initials: MA
authors.lastname: Tavill
authors.forename: S
authors.initials: S
authors.lastname: Nioka
authors.forename: T
authors.initials: T
authors.lastname: Kitai
authors.forename: B
authors.initials: B
authors.lastname: Chance
mesh_terms: D000818:Animals; D001810:Blood Volume; D010100:Oxygen / Q000032:analysis*; D010865:Pilot Projects; D011184:Postoperative Period; D013055:Spectrophotometry, Infrared; D013524:Surgical Flaps / Q000502:physiology*; D013552:Swine
chemical_list: D010100:Oxygen