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What is “normal”? And why is establishing an individualised baseline so critical?

  • When it comes to an individual patient’s measurement, “normal” can cover a wide range.
  • Establishing an individualised baseline shows you where each patient’s physiologic “normal” range begins and ends so that you can customise care for that individual.

The INVOS™ system customises care for each patient's “normal.”

  • The INVOS™ cerebral/somatic oximeter features a baseline setting that provides additional dimension and value to the rSO2 measurement.
  • Combine this baseline with continuous monitoring and the result is critical, early warnings of developing pathology and deteriorating patient condition.([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=],[LINK=]),([FOOTNOTE=Alie RF, Hymes W, Kooperman S. Intra-aortic balloon counterpulsation in an off-pump procedure shows improved cerebral perfusion by near-infrared spectroscopy. J Cardiothorac Vasc Anesth. 2010;24(2):300-302.],[ANCHOR=],[LINK=]),([FOOTNOTE=Joshi RK, Motta P, Horibe M, Mossad E. Monitoring cerebral oxygenation in a pediatric patient undergoing surgery for vascular ring. Ped Anesth. 2006;16:178-181],[ANCHOR=],[LINK=]),([FOOTNOTE=Schwartz JM, Vricella LA, Jeffries MA, Heitmiller ES. Cerebral oximetry guides treatment during Blalock-Taussig shunt procedure. J Cardiothorac Vasc Anesth. 2008;22(1):95-97. ],[ANCHOR=],[LINK=])
  • This is the kind of timely information you need—and can rely on—during surgery.

Unlike pulse oximetry, which measures arterial oxygen, the INVOS™ system measures rSO2, a reflection of cerebral venous saturation.

  • This is an important distinction, because cerebral saturation has a much wider range of normal values (45% to 75%) than arterial saturation, which has a very narrow range.
  • With this wider range of cerebral saturation, clinicians will make more informed decisions about intervention during surgery, based on the most individualised “normal” for each patient.
  • The end result? Studies have demonstrated that intervening based upon a relative drop of rSO2 from baseline improved patient outcomes.([FOOTNOTE=Murkin JM, Adams SJ, Novick RJ, et al. Monitoring brain oxygen saturation during coronary bypass surgery: a randomized, prospective study. Anesth Analg. 2007;104(1):51-58.],[ANCHOR=],[LINK=]),([FOOTNOTE=Casati A, Fanelli G, Pietropaoli P, et al. Continuous monitoring of cerebral oxygen saturation in elderly patients undergoing major abdominal surgery minimizes brain exposure to potential hypoxia. Anesth Analg. 2005;101(3):740-747.],[ANCHOR=],[LINK=])