title: Pulse oximetry.
abstract: OBJECTIVE
  Pulse oximetry is now a ubiquitous and essential tool of modern medicine, and while it is a relatively recent invention, the technology has rapidly matured since the first commercially available oximeters were introduced in the 1970s. This review seeks to provide an overview of the basic physical operation of the probe and discuss its limitations, sources of error and some current advances in the use of multi-wavelength probes.
  
  
  RESULTS
  New multi-wavelength oximeters and plethysmographic waveform analysis may expand the information that we can collect and use non-invasively. This includes distinguishing between haemoglobinopathies, monitoring volume status and volume loss, and potentially monitoring cardiac output non-invasively.
  
  
  CONCLUSIONS
  The pulse oximeter, like any basic tool, must be used properly. There is considerable misunderstanding and lack of education among junior clinicians as to the use and interpretation of pulse oximeters. The introduction of the pulse oximeter has demonstrated a cost saving, although the cost-benefit of new multi-wavelength probes remains unproven.
authors: Rotunda Hospital, Dublin, Ireland, UK. Roger_McMorrow@Bigfoot.com
authors: Roger Cn
authors: RC
authors: McMorrow
authors: Michael G
authors: MG
authors: Mythen