title: In vivo optical spectroscopy monitoring in a new model of muscular compartment syndrome.
abstract: BACKGROUND
  Muscular compartment syndrome (MCS) is a rare but serious postoperative complication. In vivo optical spectroscopy (INVOS) monitors continuously and non-invasively regional oxygen saturation (rSO(2)), and could predict the development of MCS.
  
  
  METHODS
  In 10 healthy volunteers, we inflated a tourniquet to the mean arterial pressure to produce slight venous congestion and arterial hypoperfusion. Comparisons were made between the relative reduction in rSO(2) with baseline (deltaINVOS) and the time to observe motor nerve block (with non-invasive electromyography). Neurological symptoms, pain, and invasive intracompartmental pressure (ICP) were assessed.
  
  
  RESULTS
  In the eight volunteers completing the protocol, we observed a profound motor nerve conduction block, immediately reversible. Baseline values were: [mean (sd)] INVOS: 73.3 (8.9)% and ICP: 16.9 (8.6) mm Hg. At the time of the block, values were: INVOS: 46.4 (10.9)%, deltaINVOS: 28.7 (10.6)%, and ICP: 70.0 (5.5) mm Hg. The time to reach the block was 33.0 (10.9) min, and to a deltaINVOS>10%: 27.4 (10.4) min. Receiver-operating characteristic curves demonstrated a similar accuracy of ICP and INVOS to predict the occurrence of the block. Twenty minutes with a deltaINVOS>10% or ICP>30 mm Hg were associated with a sensitivity and a specificity of 95% and 70%; or 91% and 65%, respectively.
  
  
  CONCLUSIONS
  We have developed a model of acute immediately reversible MCS. Monitoring using the INVOS technology is as accurate as measurement of ICP, and could be a useful tool to prevent development of intraoperative MCS.
authors: Department of Anesthesiology, Cliniques universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium. forgetpatrice@yahoo.fr
authors: P
authors: P
authors: Forget
authors: F
authors: F
authors: Ponchon
authors: M
authors: M
authors: Vanhoonacker
authors: G G
authors: GG
authors: Stoquart
authors: T M
authors: TM
authors: Lejeune
authors: F
authors: F
authors: Lois
authors: D
authors: D
authors: Kahn
authors: J L
authors: JL
authors: Schils
authors: M
authors: M
authors: De Kock
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D003161:Compartment Syndromes / Q000175:diagnosis*; D004576:Electromyography; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D009135:Muscular Diseases / Q000175:diagnosis*; D009407:Nerve Block; D010092:Oximetry; D010100:Oxygen / Q000097:blood; D010147:Pain Measurement / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011312:Pressure; D012372:ROC Curve; D013057:Spectrum Analysis
chemical_list: D010100:Oxygen