| abstract |
An apparatus and method of measuring blood hematocrit which involves directing first and second wavelengths of light through a blood sample, determining the ratio between pulsatile and non-pulsatile diffuse transmittances measured at each of the first and second wavelengths of light from the blood sample, and determining blood hematocrit of the blood sample from the ratio between pulsatile and non-pulsatile diffuse transmittances measured at each of the first and second wavelengths of light from the blood sample. One of the first and second wavelengths of light is within the isobestic region of oxyhemoglobin and the other is within the isobestic region of deoxyhemoglobin. A tissue phantom for simulating optical properties of a perfused finger is used to test the method and apparatus. |