Utility of near-infrared spectroscopy in the diagnosis of lower extremity compartment syndrome

Objective: To determine the utility of near-infrared spectroscopy in the diagnosis of lower extremity compartment syndrome (CS). Methods: Nine patients with CS confirmed by physical examination and elevated compartment pressures (64 +/- 17 mm Hg) were evaluated before and after fasciotomy. Control readings were also performed on 33 surgical patients who had no evidence of CS. The deltoid muscle was used as a reference value. Results: The deltoid muscle oxygen saturation (Sto(2)) readings revealed a mean = 84 +/- 17% prefasciotomy and mean = 83 +/- 12% postfasciotomy in the CS group. The control group had a mean Sto(2) of 83 +/- 11%. In the CS group, the leg compartment with the highest pressure had a Sto(2) mean = 56 +/- 27% before fasciotomy. This value was statistically significantly lower (p < 0.05) than either the postfasciotomy mean Sto(2) in that compartment (82 +/- 16%) or the values found in matched control patients with no evidence of CS (87 +/- 7%). Conclusion: Near-infrared spectroscopy-dervied Sto(2) values in the lower extremities of trauma patients with CS were diminished relative to the control patients and usually normalized after fasciotomy. Near-infrared spectroscopy evaluation may offer a rapid, noninvasive method of assessing extremities at risk for CS.