title: Relationship between near infrared spectroscopy and intra-compartmental pressures.
abstract: BACKGROUND
  Near infrared spectroscopy (NIRS) has been suggested as a possible means for detecting perfusion deficits in patients with acute compartment syndrome (ACS).
  
  
  OBJECTIVE
  To longitudinally examine NIRS in an ACS model to determine its responsiveness to decreasing perfusion pressure.
  
  
  METHODS
  A NIRS sensor pad was placed under a tourniquet over the anterior compartment in the mid-tibia region on 20 volunteers. Initial perfusion pressures and NIRS values were recorded. The tourniquet pressure was sequentially raised by 10 mm Hg in 10-min intervals until systolic pressure was surpassed. NIRS values and perfusion pressure were determined at the end of each 10-min interval.
  
  
  RESULTS
  There was no change in mean NIRS values from the initial baseline until 30 mm Hg of perfusion pressure was reached. Additionally, a statistically significant drop in mean NIRS values was observed as perfusion pressures dropped from 10 mm Hg to 0 mm Hg, and again with subsequent decreases of 10 mm Hg perfusion pressure until systolic pressure was surpassed.
  
  
  CONCLUSIONS
  These results coincide with previously published studies using alternative methods of measuring blood flow or perfusion. NIRS values were responsive to decreasing perfusion pressures over a longitudinal period of time in an ACS model. These results suggest that NIRS may be useful for continuous, non-invasive monitoring of patients for whom ACS is a concern. Additional studies on traumatized patients are required.
authors.affiliation: Emory University, Atlanta, GA 30606, USA.
authors.forename: William M
authors.initials: WM
authors.lastname: Reisman
authors.forename: Michael S
authors.initials: MS
authors.lastname: Shuler
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Kinsey
authors.forename: Ashley L
authors.initials: AL
authors.lastname: Cole
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Whitesides
authors.forename: Maria G
authors.initials: MG
authors.lastname: Davila
authors.forename: Emily K
authors.initials: EK
authors.lastname: Smith
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Moore
mesh_terms: D000208:Acute Disease; D000328:Adult; D003161:Compartment Syndromes / Q000503:physiopathology*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply; D008297:Male; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000098:blood supply*; D011446:Prospective Studies; D012039:Regional Blood Flow / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared; D014111:Tourniquets