Capnograph
Encyclopedia
A capnograph is an instrument used to measure the carbon dioxide
(CO2) concentration in an air sample. It does this by measuring the absorption
of infrared
light, which is absorbed particularly well by carbon dioxide
.
Capnographs (or capnometer) are frequently used in medicine for capnography
, measuring the carbon dioxide
content in inspired and expired air. It is a non-invasive device that measures the concentrations of respired gases using an infrared beam of light. The amount of light absorbed depends on the number of carbon dioxide molecules present in the exhaled and inhaled air. A capnograph is useful in detecting changes in carbon dioxide concentrations in patients who are hemodynamically stable, but not critically ill.
See capnography
.
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
(CO2) concentration in an air sample. It does this by measuring the absorption
Absorption (electromagnetic radiation)
In physics, absorption of electromagnetic radiation is the way by which the energy of a photon is taken up by matter, typically the electrons of an atom. Thus, the electromagnetic energy is transformed to other forms of energy for example, to heat. The absorption of light during wave propagation is...
of infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
light, which is absorbed particularly well by carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
.
Capnographs (or capnometer) are frequently used in medicine for capnography
Capnography
Capnography is the monitoring of the concentration or partial pressure of carbon dioxide in the respiratory gases. Its main development has been as a monitoring tool for use during anaesthesia and intensive care. It is usually presented as a graph of expiratory plotted against time, or, less...
, measuring the carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
content in inspired and expired air. It is a non-invasive device that measures the concentrations of respired gases using an infrared beam of light. The amount of light absorbed depends on the number of carbon dioxide molecules present in the exhaled and inhaled air. A capnograph is useful in detecting changes in carbon dioxide concentrations in patients who are hemodynamically stable, but not critically ill.
See capnography
Capnography
Capnography is the monitoring of the concentration or partial pressure of carbon dioxide in the respiratory gases. Its main development has been as a monitoring tool for use during anaesthesia and intensive care. It is usually presented as a graph of expiratory plotted against time, or, less...
.