oxygen transport


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Related to oxygen transport: carbon dioxide transport

transport

 [trans´port]
1. movement of materials in biologic systems, particularly across the cell membrane into and out of cells or across epithelial layers.
2. in the nursing interventions classification, a nursing intervention defined as moving a patient from one location to another.
active transport see active transport.
oxygen transport the carrying of oxygen through the bloodstream bound to hemoglobin (see oxyhemoglobin).
passive transport the movement of materials, usually across cell membranes, by processes not requiring expenditure of metabolic energy. See also active transport.

oxygen transport

the process by which oxygen is absorbed by red blood cell hemoglobin in the lungs and carried to the peripheral tissues. Hemoglobin combines with oxygen when present at a high concentration, such as in the lungs, and releases oxygen when the concentration is low, such as in the peripheral tissues. See also hemoglobin.
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Oxygen transport

partial pressure

the component of the total gas pressure accounted for by one gas in a mixture of gases, e.g. in air at 1 standard atmosphere (1 bar, ∼101 kPa, 760 mmHg or torr), 21% is oxygen and the partial pressure of oxygen ( P O2) is ∼21 kPa or 160 mmHg (torr). Partial pressure ( syn tension) of a gas dissolved in a liquid is defined as the partial pressure of that gas in the gaseous phase with which the liquid is, has been or would be, in equilibrium. So, given near-perfect diffusion equilibrium across the alveolar-capillary membranes, blood leaves the lungs with virtually the same P O2 and P CO2 as in alveolar gas (normally close to 100 mmHg P O2 and 40 mmHg P CO2). When blood reaches capillaries in active tissues, the lower P O2 and higher P CO2 in tissue fluids cause net molecular movement towards equilibrium, so that O2 is removed from the blood and CO2 taken up. See also carbon dioxide, diffusing capacity, gas exchange, nitrogen, oxygen, oxyhaemoglobin dissociation curve.

oxygen delivery

the rate of supply of oxygen by the arterial blood to body organs and tissues, expressed as cardiac output (L.min-1)×oxygen content of the blood (L.L-1), e.g. typical resting value would be 5 × 0.2 = 1 L.min-1. This is four times the typical oxygen usage at rest, since only a quarter of the oxygen in the arterial blood is removed by the tissues, reducing haemoglobin saturation from 100% to 75%. See also oxyhaemoglobin dissociation curve.
Oxygen in the blood: the oxyhaemoglobin dissociation curve. a1, a2: arterial blood at altitudes of ∼2500m and ∼5000m.

oxyhaemoglobin dissociation curve

the graph which describes the relationship in the blood between partial pressure of oxygen ( P O2) and the percentage saturation of haemoglobin; it can also show the equivalent oxygen content of the blood when haemoglobin is in normal concentration. With normal lungs, saturation in arterial blood is determined by the P O2 in the alveolar gas with which pulmonary capillary blood equilibrates. The S-shape of the curve has important physiological advantages, e.g. a relatively small decrease in P O2 encountered where blood flows through tissues causes a 'steep' removal of oxygen from the blood; but there needs to be a relatively large decrease in P O2 in the inspired air (and therefore in the alveoli, e.g. at altitude or in a confined space) before there is a serious decline in haemoglobin saturation. ( See fig overleaf .)

oxygen

a chemical element, atomic number 8, atomic weight 15.999, symbol O. See Table 6. It is a colorless and odorless gas that makes up about 20% of the atmosphere. In combination with hydrogen, it forms water; by weight, 90% of water is oxygen. It is the most abundant of all the elements of nature. Large quantities of it are distributed throughout the solid matter of the earth, because the gas combines readily with many other elements. With carbon and hydrogen, oxygen forms the chemical basis of much organic material. Oxygen is essential in sustaining all kinds of life.

oxygen analyzer
an instrument that measures the concentration of oxygen in a gas mixture.
oxygen deficiency
significant cause of losses in cultivated finfish in enclosed dams, but also in rivers and estuaries, caused by lack of natural aeration of the water or to heavy algal blooms, bushfire ash deposits and overcast conditions leading to respiration rather than photosynthesis or a high concentration of organic matter and leading to the development of a bacterial bloom; a high temperature exacerbates the development.
oxygen flux equation
a calculation that determines the rate at which oxygen is made available to tissues, based on cardiac output and arterial oxygen content.
oxygen-hemoglobin dissociation curve
a graphic explanation of the release and acquisition of oxygen from and to the hemoglobin in the blood in varying circumstances of oxygen partial pressure in the environment.
oxygen regulator
see reducing valve.
oxygen saturation
the amount of oxygen bound to hemoglobin in the blood expressed as a percentage of the maximal binding capacity.
oxygen saturation curve
graphical representation describing the relationship (usually curvilinear) between fraction of oxygen-binding sites (of a protein) that have oxygen bound to them and the partial pressure (concentration) of free oxygen.
oxygen tank
the heavy metal cylinder in which medical gases are compressed at high pressure. Called also oxygen cylinder.
oxygen tension
see tension (2).
oxygen tent
an enclosed space or plastic canopy used for oxygen therapy, humidity therapy or aerosol therapy.
oxygen therapy
supplemental oxygen administered for the purpose of relieving hypoxemia and preventing damage to the tissue cells as a result of oxygen lack (hypoxia). Companion animals are usually placed in a special cage with oxygen piped to it. A mask is used for short-term administration. Large animals can be supplied by a nasal tube taped in place to deliver oxygen into the pharynx.
oxygen toxicity
tissue damage may occur with exposure to high concentrations of oxygen for long periods. See also retrolental fibroplasia.
oxygen-transfer chain
a functional chain describing the transfer of oxygen from the external environment to the metabolizing tissue; includes uptake in the respiratory system, binding to hemoglobin, transport through the circulatory system, diffusion and dissociation in tissues and utilization in mitochondria, i.e. oxidatable substrates and enzymes.
oxygen transport
process of transfer of oxygen around the body either attached to hemoglobin or myoglobin.
References in periodicals archive ?
The group combines the hydrogen transport membrane (HTM) and oxygen transport membrane (OTM) technologies CoorsTek, Ceramatec, and Protia (both CoorsTek companies) have been developing over the past two decades and are now commercializing with energy and chemical producers.
The oxygen transport potential of blood specimens was calculated as the ratio of haematocrit to blood viscosity (11).
Cook and Knight (2003a) suggested that such arbitrary definitions of the aeration limit are unlikely to be universal, as oxygen transport rate in relation to the consumptive sinks will actually determine an upper limit in concepts such as LLWR, and alternative modelling approaches may be better if they can account for the consumptive sinks.
The researchers compared the properties of blood pigment haemocyanin, responsible for oxygen transport, of Antarctic, Temperate and Warm-Adapted octopods.
Innes, AJ and Wells RMG: Respiration and oxygen transport functions of the blood from an intertidal fish, Helcogramma medium (Tripterygiidae).
In the clinical setting it is vitally important to consider Hb levels when evaluating oxygen transport to the tissues.
Oxygen Transport in Hybrid Layer With Oil Ratio 70/30 Coated on Different Substrates
Specific threats to tissue oxygen supply occur whenever cardiac output, oxygen transport or arterial oxygen saturation are altered.
In this revision of the 1995 edition, Watchie (an independent health, wellness and fitness professional, Los Angeles) and several other contributing physical therapists explain why the oxygen transport system is so important to therapists working with patients with cardiovascular or pulmonary problems.
The oxygen transport process continues when right ventricular systole ejects mixed-venous blood into the pulmonary circulation for another encounter with alveolar gas.
The final equation for oxygen transport can be given as follows; taking into account Equation 3 and noting that the volumetric consumption of the oxygen within the waste dump is controlled by first-order kinetics.
623 was predicted as oxygen transporter activity for molecular function and oxygen transport for biological process, indicating complete recovery.