Article

Noninvasive cerebral oximetry: Is there light at the end of the tunnel?

Department of Neurocritical Care, The National Hospital for Neurology and Neurosurgery, University College London Hospitals, Queen Square, London, UK.
Current opinion in anaesthesiology (Impact Factor: 2.53). 10/2010; 23(5):576-81. DOI: 10.1097/ACO.0b013e32833e1536
Source: PubMed

ABSTRACT There is increasing interest in the application of near infrared spectroscopy (NIRS) as a noninvasive monitor of cerebral oxygenation. This review will briefly describe the principles of NIRS and examine current evidence for its clinical application as a monitor of the adequacy of cerebral oxygenation in adults.
There has been a recent surge of interest in the clinical application of NIRS following studies that have quantified the benefits of NIRS-guided management of cerebral oxygenation during cardiopulmonary bypass. However, there are limited data to support its widespread application in other clinical scenarios. New NIRS systems are being introduced to the market and technological advancements have improved their accuracy and extended the range of variables measured.
NIRS offers noninvasive monitoring of cerebral oxygenation over multiple regions of interest in a wide range of clinical scenarios. It has many potential advantages over other neuromonitoring techniques, but further technological advances are necessary before it can be introduced more widely into clinical practice.

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    • "Furthermore, as compared to fMRI, fNIRS provides a more direct measure of changes in HbO, HbR, and total hemoglobin (HbT), and the time series are sampled at high temporal resolution . It has therefore proved to be an effective tool for studying physiological mechanisms in the healthy brain and in cerebrovascular disease (Highton et al., 2010; Wolf et al., 2012; Obrig, 2014). It is also finding unique applications in clinical areas, including bedside monitoring of infants, and studies of auditory and language systems (Lloyd-Fox et al., 2010; Eggebrecht et al., 2014). "
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    • "Conversely to the commercially available devices, they supply measures of HbO 2 and HbH in addition to rSO 2 through nonadhesive sensors that can be more easily placed in various regions of the head. The use of these various instruments or systems makes it difficult to interpret findings between studies (Highton et al., 2010). Nonetheless, the Invos 5100B and Niro 300 devices have been shown to produce very similar results with overall bias of À2.1% (limits of agreement of AE14.7%) (Thavasothy, Broadhead, 523 Innovating in Pain Assessment of the Critically Ill Elwell, Peters, & Smith, 2002). "
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    • "Conversely to the commercially available devices, they supply measures of HbO 2 and HbH in addition to rSO 2 through nonadhesive sensors that can be more easily placed in various regions of the head. The use of these various instruments or systems makes it difficult to interpret findings between studies (Highton et al., 2010). Nonetheless, the Invos 5100B and Niro 300 devices have been shown to produce very similar results with overall bias of À2.1% (limits of agreement of AE14.7%) (Thavasothy, Broadhead, 523 Innovating in Pain Assessment of the Critically Ill Elwell, Peters, & Smith, 2002). "
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