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Oxygen Saturation (medicine)
Oxygen saturation is the fraction of oxygen-saturated haemoglobin relative to total haemoglobin (unsaturated + saturated) in the blood. The human body requires and regulates a very precise and specific balance of oxygen in the blood. Normal arterial blood oxygen saturation levels in humans are 96–100 percent. If the level is below 90 percent, it is considered low and called hypoxemia. Arterial blood oxygen levels below 80 percent may compromise organ function, such as the brain and heart, and should be promptly addressed. Continued low oxygen levels may lead to respiratory or cardiac arrest. Oxygen therapy may be used to assist in raising blood oxygen levels. Oxygenation occurs when oxygen molecules () enter the tissues of the body. For example, blood is oxygenated in the lungs, where oxygen molecules travel from the air and into the blood. Oxygenation is commonly used to refer to medical oxygen saturation. Definition In medicine, oxygen saturation, commonly referred to as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse Oximeter
Pulse oximetry is a noninvasive method for monitoring blood oxygen saturation. Peripheral oxygen saturation (SpO2) readings are typically within 2% accuracy (within 4% accuracy in 95% of cases) of the more accurate (and invasive) reading of arterial oxygen saturation (SaO2) from arterial blood gas analysis. A standard pulse oximeter passes two wavelengths of light through tissue to a photodetector. Taking advantage of the pulsate flow of arterial blood, it measures the change in absorbance over the course of a cardiac cycle, allowing it to determine the absorbance due to arterial blood alone, excluding unchanging absorbance due to venous blood, skin, bone, muscle, fat, and, in many cases, nail polish. The two wavelengths measure the quantities of bound (oxygenated) and unbound (non-oxygenated) hemoglobin, and from their ratio, the percentage of bound hemoglobin is computed. The most common approach is ''transmissive pulse oximetry''. In this approach, one side of a thin part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Infrared Spectroscopy
Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 nm to 2500 nm). Typical applications include medical and physiological diagnostics and research including blood sugar, pulse oximetry, functional neuroimaging, sports medicine, elite sports training, ergonomics, Physical therapy, rehabilitation, neonatal research, brain computer interface, urology (bladder contraction), and neurology (neurovascular coupling). There are also applications in other areas as well such as pharmaceutical, food and agrochemical quality control, atmospheric chemistry, combustion propagation. Theory Near-infrared spectroscopy is based on molecular overtone and combination vibrations. Overtones and combinations exhibit lower intensity compared to the fundamental, as a result, the molar absorptivity in the near-IR region is typically quite small. (NIR absorption bands are typically 10–100 times weaker than the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extracorporeal Membrane Oxygenation
Extracorporeal membrane oxygenation (ECMO) is a form of extracorporeal life support, providing prolonged cardiac and respiratory system, respiratory support to people whose human heart, heart and human lung, lungs are unable to provide an adequate amount of oxygen, gas exchange or blood supply (perfusion) to sustain life. The technology for ECMO is largely derived from cardiopulmonary bypass, which provides shorter-term support with arrested native circulation. The device used is a membrane oxygenator, also known as an artificial lung. ECMO works by temporarily drawing blood from the body to allow artificial oxygenation of the red blood cells and removal of carbon dioxide. Generally, it is used either post-cardiopulmonary bypass or in late-stage treatment of a person with profound heart and/or lung failure, although it is now seeing use as a treatment for cardiac arrest in certain centers, allowing treatment of the underlying cause of arrest while circulation and oxygenation are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart Lung Machine
Cardiopulmonary bypass (CPB) or heart-lung machine, also called the pump or CPB pump, is a machine that temporarily takes over the function of the heart and lungs during open-heart surgery by maintaining the circulation of blood and oxygen throughout the body. As such it is an extracorporeal device. CPB is operated by a perfusionist. The machine mechanically circulates and oxygenates blood throughout the patient's body while bypassing the heart and lungs allowing the surgeon to work in a bloodless surgical field. Uses CPB is commonly used in operations or surgical procedures involving the heart. The technique allows the surgical team to oxygenate and circulate the patient's blood, thus allowing the surgeon to operate safely on the heart. In many operations, such as coronary artery bypass grafting (CABG), the heart is arrested, due to the degree of the difficulty of operating on a beating heart. Operations requiring the opening of the chambers of the heart, for example mitra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischemic
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue, i.e., hypoxia and microvascular dysfunction. It also implies local hypoxia in a part of a body resulting from constriction (such as vasoconstriction, thrombosis, or embolism). Ischemia causes not only insufficiency of oxygen but also reduced availability of nutrients and inadequate removal of metabolic wastes. Ischemia can be partial (poor perfusion) or total blockage. The inadequate delivery of oxygenated blood to the organs must be resolved either by treating the cause of the inadequate delivery or reducing the oxygen demand of the system that needs it. For example, patients with myocardial ischemia have a decreased blood flow to the heart and are prescribed w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanosis
Cyanosis is the change of Tissue (biology), tissue color to a bluish-purple hue, as a result of decrease in the amount of oxygen bound to the hemoglobin in the red blood cells of the capillary bed. Cyanosis is apparent usually in the Tissue (biology), body tissues covered with thin skin, including the mucous membranes, lips, nail beds, and ear lobes. Some medications may cause discoloration such as medications containing amiodarone or silver. Furthermore, mongolian spots, large birthmarks, and the consumption of food products with blue or purple dyes can also result in the bluish skin tissue discoloration and may be mistaken for cyanosis. Appropriate physical examination and history taking is a crucial part to diagnose cyanosis. Management of cyanosis involves treating the main cause, as cyanosis is not a disease, but rather a symptom. Cyanosis is further classified into central cyanosis and peripheral cyanosis. Pathophysiology The mechanism behind cyanosis is different dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemia
Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin available for oxygen transport, or abnormalities in hemoglobin that impair its function. The name is derived . When anemia comes on slowly, the symptoms are often vague, such as Fatigue, tiredness, weakness, shortness of breath, headaches, and a Exercise intolerance, reduced ability to exercise. When anemia is acute, symptoms may include confusion, lightheadedness, feeling like one is going to pass out, Syncope (medicine), loss of consciousness, and polydipsia, increased thirst. Anemia must be significant before a person becomes noticeably Pallor, pale. Additional symptoms may occur depending on the underlying cause. Anemia can be temporary or long term and can range from mild to severe. Anemia can be caused by blood loss, decreased red blood cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arterial Blood Gas Test
An arterial blood gas (ABG) test, or arterial blood gas analysis (ABGA) measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle, but sometimes the femoral artery in the groin or another site is used. The blood can also be drawn from an arterial catheter. An ABG test measures the blood gas tension values of the arterial partial pressure of oxygen (PaO2), and the arterial partial pressure of carbon dioxide (PaCO2), and the blood's pH. In addition, the arterial oxygen saturation (SaO2) can be determined. Such information is vital when caring for patients with critical illnesses or respiratory disease. Therefore, the ABG test is one of the most common tests performed on patients in intensive-care units. In other levels of care, pulse oximetry plus transcutaneous carbon-dioxide measurement is a less invasive, alternative method of obtaining s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (medical)
Hypoxia is a condition in which the body or a region of the body is deprived of an adequate oxygen supply at the tissue (biology), tissue level. Hypoxia may be classified as either ''Generalized hypoxia, generalized'', affecting the whole body, or ''local'', affecting a region of the body. Although hypoxia is often a pathological condition, variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise. Hypoxia differs from hypoxemia and anoxemia, in that hypoxia refers to a state in which oxygen present in a tissue or the whole body is insufficient, whereas hypoxemia and anoxemia refer specifically to states that have low or no Oxygen saturation (medicine), oxygen in the blood. Hypoxia in which there is complete absence of oxygen supply is referred to as anoxia. Hypoxia can be due to external causes, when the breathing gas is hypoxic, or internal causes, such as reduced effectiveness of gas transfer in the lung ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperoxia
Hyperoxia is the state of being exposed to high levels of oxygen; it may refer to organisms, cells and tissues that are experiencing excessive oxygenation, or to an abnormally high oxygen concentration in an environment (e.g. a body of water). In medicine, it refers to excessive oxygen in the lungs or other body tissues, and results from raised alveolar oxygen partial pressure ― that is, alveolar oxygen partial pressure greater than that due to breathing air at normal (sea level) atmospheric pressure. This can be caused by breathing air at a pressure above normal or by breathing other gas mixtures with a high oxygen fraction, high ambient pressure or both. The body is tolerant of some deviation from normal inspired oxygen partial pressure, but a sufficiently elevated level of hyperoxia can lead to oxygen toxicity over time, with the mechanism related to the partial pressure, and the severity related to the dose. Hyperoxia is the opposite of hypoxia; hyperoxia refers to a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
