Objective. The aim of our prospective study was to investigate the applicability and the diagnostic value of near-infrared spectroscopy (NIRS) in SAH patients using the cerebral oximeter INVOS 5100C. Methods. Measurement of cerebral oximetry was done continuously after spontaneous SAH. Decrease of regional oxygen saturation (rSO2) was analyzed and interpreted in view of the determined intrinsic and extrinsic factors. Changes of rSO2 values were matched with the values of ICP, tipO2, and TCD and the results of additional neuroimaging. Results. Continuous measurement of rSO2 was performed in nine patients with SAH (7 females and 2 males). Mean measurement time was 8.6 days (range 2–12 days). The clinical course was uneventful in 7 patients without occurrence of CVS. In these patients, NIRS measured constant and stable rSO2 values without relevant alterations. Special findings are demonstrated in 3 cases. Conclusion. Measurement of rSO2 with NIRS is a safe, easy to use, noninvasive additional measurement tool for cerebral oxygenation, which is used routinely during vascular and cardiac surgical procedures. NIRS is applicable over a long time period after SAH, especially in alert patients without invasive probes. Our observations were promising, whereby larger studies are needed to answer the open questions.
Continuous Measurement of Nitrate Concentration in Whole Lettuce Plant by Visible-near-infrared Spectroscopy
