Pulse oximetry probes placed peripherally may fail to give accurate values of blood oxygen saturation when the peripheral circulation is poor. Because central blood flow may be preferentially preserved, we investigated the oesophagus as an alternative monitoring site. A reflectance blood oxygen saturation probe was developed and evaluated in 49 patients undergoing cardiothoracic surgery. The oe...

Microcirculatory dysfunction is very common in sepsis and may results in organ failure and increased risk of death. Analyzing oxygen utilization can potentially assess microcirculation function of an individual. In this study, a modified pulse oximeter is used to extract information signals due to absorption of red (R) and infrared (IR) light. IR and R signal are related to the overall blood vo...

Pulse oximetry is a non-invasive method for monitoring a person's O2 saturation. In its most common (transmissive) application mode, a sensor device is placed on a thin part of the patient's body, usually a fingertip orearlobe, or in the case of an infant, across a foot. The device passes two wavelengths of light through the body part to a photodetector. It measures the changing absorbance at e...

BACKGROUND A new eight-wavelength pulse oximeter is designed to measure methemoglobin and carboxyhemoglobin, in addition to the usual measurements of hemoglobin oxygen saturation and pulse rate. This study examines this device's ability to measure dyshemoglobins in human volunteers in whom controlled levels of methemoglobin and carboxyhemoglobin are induced. METHODS Ten volunteers breathed 50...

The measurement of tissue oxygen saturation with a pulse oximeter is of proved value in the hospital setting. The development of a portable oximeter has allowed this investigation to be performed during the prehospital phase of a patient's care. Pulse oximetry was performed at the roadside in 25 patients with abnormal trauma scores and found to be of benefit in detecting and monitoring hypoxia ...

Pulse oximeters have become standard equipment in both biomedical education and clinical settings. Since the operational principles of a pulse oximeter are straightforward, and since the analysis of these sensor data require basic computational and mathematical toolsets, this type of device is well suited to hands-on experiences geared toward both undergraduate and graduate students. However, t...