A spectroscopic approach will be developed for analysis ofblood during manned space missions directly through the skin by usinglight from a laser diode array reflected from a prominent vein near theskin surface in either the wrist or ankle region of the body. The laserdiodes will operate at low power, causing no tissue injury, and atspecific wavelengths in the red and near infrared, wavelengths at whichskin and venous tissue are known to be transparent to a depth of severalmillimeters. The reflected light at each of the selected probewavelengths will then be measured. The reflected intensities from eachprobe wavelength are analyzed in two modes: the specific reflectanceratios among the probe wavelengths will be determined and used toidentify blood components present in the monitored patient'scirculatory system; and if the ratios of key selected wavelengths remainunchanged, the reflectance intensity will be used to monitor changes inred cell (hematocrit) concentration.The product, a noninvasive blood monitor, would be widely useful in thepractice of medicine.noninvasive blood analysis, reflectance spectroscopySTATUS: Phase I Only
