• Exactly what does “absolute intervention threshold” or “absolute accuracy” mean? At this time, the FDA has no defined parameters for these marketing terms.
  • Current cerebral oximeter technology does not allow for “absolute” measurements. The only real way to measure “absolute” cerebral oxygenation levels is to sample blood from a patient’s brain, which oximeters don’t do.
  • “Absolute intervention thresholds” or “absolute accuracy” alone are not definitive of a patient’s full physiologic condition. Each patient is unique and there is a wide range of normal values for cerebral venous oxygenation, which is contrary to an absolute measurement threshold for intervention.([FOOTNOTE=Aron JH, Fink GW, Swartz MF, et al. Cerebral oxygen desaturation after cardiopulmonary bypass in a patient with Raynaud’s phenomenon detected by near-infrared cerebral oximetry. Anesth Analg. 2007;104(5):1034-1036.],[ANCHOR=View Abstract],[LINK=/content/covidien/websites/medtronic/com/en/covidien/support/clinical-evidence.html?id=297569])