HISTORY AND RECENT DEVELOPMENTS IN PULSE OXIMETRY

To honour Siggaard-Andersen's role in the development of accurate bloo d oximetry, this paper was abstracted from a recent review and survey of over 750 publications of pulse oximetry [1]. Pulse oximetry usage h as become nearly universal during anesthesia and related critical care in the developed world during the last decade. More than 35 manufactu rers offer pulse oximetry. Costs of some have fallen to less than $150 0 per device, with no necessary on-going charges. Pulse oximeters are remarkable: Accuracy is +/-2 % down to 70 % SaO2 WithoUt any user cali bration, no drift, instantaneous readout, and almost no maintenance or safety problems. New developments include better understanding of man agement of premature infants, beginning use for fetal SaO2 during labo r, sophisticated methods of ignoring motion artifacts and room light i nterference, and awareness of sources of error. Oximetry use has cause d anesthesiologists and most critical care physicians to become far mo re able to avoid severe hypoxia in patients. Malpractice insurance rat es for anesthesiologists have dropped in the USA, and other evidence s uggests, although failing to prove, that anesthesia and critical care is now safer, probably due to oximetry.