Optics: measuring and testing – Blood analysis – Hemoglobin concentration
Patent
1989-05-30
1990-11-06
Mis, David
Optics: measuring and testing
Blood analysis
Hemoglobin concentration
356 42, 356243, 2502521, 128633, G01N 3348
Patent
active
049681370
ABSTRACT:
A device and method for calibration of pulse oximeters is disclosed. A standard specimen that has optical characteristics of hemoglobin of a known oxygen saturation is placed in the light path of a pulse oximeter probe. The image of a pulse is created by a filter that periodically increases and decreases the amount of light allowed to reach the sensor of the probe. In one embodiment, the filter comprises a pair of polarizing filters rotated with respect to one another under the control of a digital computer with a motor interface device. In another embodiment, a wedge of a light-attenuating medium, such as a cuvette containing oxygenated blood, is reciprocated in the light path, the wide portions of the wedge attenuating a greater amount of light than the narrow portions. Such a cuvette can include filler openings, with outwardly extending tubes at both the wide and narrow ends. For comparison testing, the cuvette can include a sample of blood from a test subject, the blood having been oxygenated to a known oxygen content. A light-attenuating layer, with light transmissivity characteristics that are additive to those of the filter, can be provided in the light path to simulate an abnormal blood condition, such as the presence of carboxyhemoglobin, methemoglobin, or venous blood.
REFERENCES:
patent: 4167331 (1979-09-01), Nielsen
patent: 4650327 (1987-03-01), Ogi
patent: 4744656 (1988-05-01), Moran et al.
Mark Yelderman and William New, "Evaluation of Pulse Oximetry", The Journal of Anesthesiology, vol. 59:349-352 (Oct. 1983).
"Smart Oximeter Helps Trim Saturation Speculation", Anesthesiology Topics, vol. 3, No. 3 (May-Jun. 1984).
M. Chung, M.D. et al., "Transcutaneous Monitoring of PO.sub.2 and PCO.sub.2 During One-Lung Anesthesia", Anesthesiology, vol. 61, No. 3A, A164 (Sep. 1984 Supplement).
Christopher Glazener, M.D. et al., "Hypoxemia in Children Following General Anesthesia", anesthesiology, vol. 61, No. 3A, A164 (Sep. 1984 Supplement).
D. P. Lobo, M.D. et al., "Monitoring High Frequency Jet Ventilation During Anesthesia", Anesthesiology, vol. 61, No. 3A, A171 (Sep. 1984 Supplement).
F. G. Mihm, M.D. et al., "Non-Invasive Monitoring of Respiratory Failure with Pulse Oximetry and Capnography", Anesthesiology, vol. 59, No. 3, A136 (Sep. 1983 Supplem't).
Frank Monaco, et al., "Continuous Noninvasive Oxygen Saturation Monitoring in Sick Newborns", Respiratory Care, vol. 28, No. 10 (Oct. 1983).
M. S. Shulman, M.D., et al., "Non-Invasive Pulse Oximetry During One-Lung Ventilation", Anesthesiology, vol. 61, No. 3A, A98 (Sep. 1984 Supplement).
David B. Swedlow and Sydney Stern, "Continuous Non-Invasive Oxygen Saturation Monitoring in Children with a New Pulse-Oximeter", Critical Care Medicine, vol. 12, No. 3 (Mar. 1983).
Andrew R. Wilkerson, et al., "Continuous in Vivo Oxygen Saturation in Newborn Infants with Pulmonary Disease", Critical Care Medicine, vol. 7, No. 5 (May 1979).
Andrew R. Wilkerson, et al., "In Vivo Oxygen Dissociation Curves in Transfused and Untransfused Newborns with Cardiopulmonary Disease", American Review of Respiratory Disease, 122:629-634 (1980).
Mis David
The State of Oregon Acting by and through the State Board of Hig
LandOfFree
Devices and procedures for in vitro testing of pulse oximetry mo does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Devices and procedures for in vitro testing of pulse oximetry mo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Devices and procedures for in vitro testing of pulse oximetry mo will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1303756