Pulse oximetry is a non-invasive method which allows health care providers to monitor the oxygenation of a patient's blood. The term non-invasive in medicine has two meanings: A medical procedure which does not penetrate or break the skin or a body cavity, i. ... Oxygenation refers to the amount of oxygen in a medium. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...

A sensor is placed on a relatively thin part of the patient's anatomy, usually a fingertip or earlobe, and red and infrared light is passed from one side to the other. Based upon the ratio of absorption of the red and infrared light caused by the difference in color between oxygen-bound (red) and unbound (blue) hemoglobin in the capillary bed, an approximation of oxygenation can be made. Anatomical drawing of the human muscles from the Encyclopédie. ... For the network protocol, see finger protocol. ... For an alternative meaning, see ear (botany). ... 3-dimensional structure of hemoglobin. ... Capillaries are the smallest of a bodys blood vessels, measuring 5-10 μm. ... Oxygenation refers to the amount of oxygen in a medium. ...

This is especially useful in an intensive care setting, for assessment of emergency patients, determining the effectiveness of or need for supplemental oxygen, as well as monitoring during anesthesia and during post-anesthetic care. Assessing a pateint's need for supplemental oxygen is useful in the detection and prevention of hypoxemia. Although pulse oximetry is used to monitor oxygenation, it is possible that it can also be used to detect abnormalities in ventilation. However, the use of pulse oximetry to detect hypoventilation is impaired with the use of supplemental oxygen, as it is only when patients breathe room air that abnormalities in respiratory function can be detected reliably with its use. Therefore, the routine administration of supplemental oxygen may be unwarranted if the patient is able to maintain adequate oxygenation in room air, since it can result in hypoventilation going undetected. Intensive care medicine or critical care medicine is concerned with providing greater than ordinary medical care and observation to people in a critical or unstable condition. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... Cetacaine, a typical topical anesthetic Anesthesia or anaesthesia (see spelling differences), is the process of blocking the perception of pain and other sensations. ... Hypoxia is a pathological condition in which the body as a whole (generalized hypoxia) or region of the body (tissue hypoxia) is deprived of adequate oxygen supply. ... In medicine, hypoventilation exists when ventilation is inadequate (hypo) to perform gas exchange. ...

It should be noted that this is a measure solely of oxygenation, not of ventilation, and is not a substitute for blood gases checked in a laboratory as it gives no indication of carbon dioxide levels, blood pH, or sodium bicarbonate levels. While oximetry does indicate the patient's pulse rate, it does not measure pulse intensity and therefore should not substitute for more accurate methods of pulse reading. Ventilation good and very bad Ventilation is air circulation of air, typically between a room, a tunnel, etc. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ... The title of this article should be pH. The initial letter is capitalized due to technical restrictions. ... Sodium bicarbonate NaHCO3, or sodium hydrogen carbonate, also known as baking soda, bread soda, or bicarbonate of soda, is a soluble white anhydrous or crystalline chemical compound, with a slight alkaline taste resembling that of sodium carbonate. ...

Falsely low readings may be caused by hypoperfusion of the extremity being used for monitoring (often due to the part being cold or from vasoconstriction secondary to the use of vasopressor agents); incorrect sensor application; highly caloused skin; and movement (such as shivering), especially during hypoperfusion. To ensure accuracy, the sensor should return a steady pulse and/or pulse waveform. Falsely high or falsely low readings will occur when hemoglobin is bound to something other than oxygen. In cases of carbon monoxide poisoning, the falsely high reading may delay the recognition of hypoxemia (low blood oxygen level). Cyanide poisoning can also give a false high reading. In medicine, shock (hypoperfusion) is a life-threatening medical emergency characterized by inability of the body to supply enough oxygen to meet tissue requirements. ... The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... In medicine, shock (hypoperfusion) is a life-threatening medical emergency characterized by inability of the body to supply enough oxygen to meet tissue requirements. ... Carbon monoxide, chemical formula CO, is a colorless, odorless, tasteless, flammable and highly toxic gas. ... Hypoxia is a pathological condition in which the body as a whole (generalized hypoxia) or region of the body (tissue hypoxia) is deprived of adequate oxygen supply. ... A space-filling model of the cyanide ion A cyanide is any chemical compound that contains the cyano group -C≡N, with the carbon atom triple-bonded to the nitrogen atom. ...

See also

• Oxygen sensor
• Oxygen saturation
• Pulse oximeter

An oxygen sensor is an electronic device that measures the proportion of oxygen in the gas or liquid being analyzed. ... Oxygen saturation is a relative measure of the amount of oxygen that is dissolved or carried in a given medium. ... A portable saturometer (for emergencies) Measure by optic properties through the nail A pulse oximeter is a medical device that indirectly measures the amount of oxygen in a patients blood. ...

External links

• Learn how an oximeter works by building an optical heart rate monitor