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Respiratory Compensation
Respiratory compensation is the modulation by the brainstem respiratory centers, which involves altering alveolar ventilation to try and bring the plasma pH back to its normal value (7.4) in order to keep the acid-base balance in the body. It usually occurs within minutes to hours and is much faster than renal compensation (takes several days), but has less ability to restore normal values. In metabolic acidosis, chemoreceptors sense a deranged acid-base balance with a plasma pH of lesser than normal (7.4). The chemoreceptors send afferent fibers to the brainstem respiratory centers. The brainstem respiratory centers decrease alveolar ventilation (hypoventilation) to create a rise in arterial carbon dioxide () tension, resulting in a decrease of plasma pH. However, as there is limitation for decreasing respiration, respiratory compensation is less efficient at compensating for metabolic alkalosis than for acidosis. The respiratory brainstem centers can only compensate for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonology
Pulmonology (, , from Latin ''pulmō, -ōnis'' "lung" and the Ancient Greek, Greek suffix "study of"), pneumology (, built on Greek πνεύμων "lung") or pneumonology () is a specialty (medicine), medical specialty that deals with Respiratory disease, diseases involving the respiratory tract.ACP: Pulmonology: Internal Medicine Subspecialty . Acponline.org. Retrieved on 2011-09-30. It is also known as respirology, respiratory medicine, or chest medicine in some countries and areas. Pulmonology is considered a branch of internal medicine, and is related to intensive care medicine. Pulmonology often involves managing patients who need life support and mechanical ventilation. Pulmonologists are specially trained in diseases and conditions of the chest, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Center
The respiratory center is located in the medulla oblongata and pons, in the brainstem. The respiratory center is made up of three major respiratory groups of neurons, two in the medulla and one in the pons. In the medulla they are the dorsal respiratory group, and the ventral respiratory group. In the pons, the pontine respiratory group includes two areas known as the pneumotaxic centre and the apneustic centre. The respiratory centre is responsible for generating and maintaining the rhythm of respiration, and also of adjusting this in homeostatic response to physiological changes. The respiratory center receives input from chemoreceptors, mechanoreceptors, the cerebral cortex, and the hypothalamus in order to regulate the rate and depth of breathing. Input is stimulated by altered levels of oxygen, carbon dioxide, and blood pH, by hormonal changes relating to stress and anxiety from the hypothalamus, and also by signals from the cerebral cortex to give a conscious contro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Ventilation
Breathing (or ventilation) is the process of moving air into and from the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxygen. All aerobic creatures need oxygen for cellular respiration, which extracts energy from the reaction of oxygen with molecules derived from food and produces carbon dioxide as a waste product. Breathing, or "external respiration", brings air into the lungs where gas exchange takes place in the alveoli through diffusion. The body's circulatory system transports these gases to and from the cells, where "cellular respiration" takes place. The breathing of all vertebrates with lungs consists of repetitive cycles of inhalation and exhalation through a highly branched system of tubes or airways which lead from the nose to the alveoli. The number of respiratory cycles per minute is the breathing or respiratory rate, and is one of the four primary vital signs of life. Under normal conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid–base Homeostasis
Acid–base homeostasis is the homeostatic regulation of the pH of the body's extracellular fluid (ECF). The proper balance between the acids and bases (i.e. the pH) in the ECF is crucial for the normal physiology of the body—and for cellular metabolism. The pH of the intracellular fluid and the extracellular fluid need to be maintained at a constant level. The three dimensional structures of many extracellular proteins, such as the plasma proteins and membrane proteins of the body's cells, are very sensitive to the extracellular pH. Stringent mechanisms therefore exist to maintain the pH within very narrow limits. Outside the acceptable range of pH, proteins are denatured (i.e. their 3D structure is disrupted), causing enzymes and ion channels (among others) to malfunction. An acid–base imbalance is known as acidemia when the pH is acidic, or alkalemia when the pH is alkaline. Lines of defense In humans and many other animals, acid–base homeostasis is mainta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renal Compensation
Renal compensation is a mechanism by which the kidneys can regulate the plasma pH. It is slower than respiratory compensation, but has a greater ability to restore normal values. In respiratory acidosis, the kidney produces and excretes ammonium (NH4+) and monophosphate, generating bicarbonate in the process while clearing acid. In respiratory alkalosis, less bicarbonate In inorganic chemistry, bicarbonate (IUPAC-recommended nomenclature: hydrogencarbonate) is an intermediate form in the deprotonation of carbonic acid. It is a polyatomic anion with the chemical formula . Bicarbonate serves a crucial biochemi ... (HCO3−) is reabsorbed, thus lowering the pH. References {{Renal physiology Acid–base disturbances ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Acidosis
Metabolic acidosis is a serious electrolyte disorder characterized by an imbalance in the body's acid-base balance. Metabolic acidosis has three main root causes: increased acid production, loss of bicarbonate, and a reduced ability of the kidneys to excrete excess acids. Metabolic acidosis can lead to acidemia, which is defined as arterial blood pH that is lower than 7.35. Acidemia and acidosis are not mutually exclusive – pH and hydrogen ion concentrations also depend on the coexistence of other acid-base disorders; therefore, pH levels in people with metabolic acidosis can range from low to high. Acute metabolic acidosis, lasting from minutes to several days, often occurs during serious illnesses or hospitalizations, and is generally caused when the body produces an excess amount of organic acids (ketoacids in ketoacidosis, or lactic acid in lactic acidosis). A state of chronic metabolic acidosis, lasting several weeks to years, can be the result of impaired kidney function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemoreceptors
A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance ( endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemoreceptor is a neuron, or in the form of a neurotransmitter that can activate a nerve fiber if the chemoreceptor is a specialized cell, such as taste receptors, or an internal peripheral chemoreceptor, such as the carotid bodies. In physiology, a chemoreceptor detects changes in the normal environment, such as an increase in blood levels of carbon dioxide (hypercapnia) or a decrease in blood levels of oxygen (hypoxia), and transmits that information to the central nervous system which engages body responses to restore homeostasis. In bacteria, chemoreceptors are essential in the mediation of chemotaxis. Cellular chemoreceptors In prokaryotes Bacteria utilize complex long helical proteins as chemoreceptors, permitting signals to travel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Center
The respiratory center is located in the medulla oblongata and pons, in the brainstem. The respiratory center is made up of three major respiratory groups of neurons, two in the medulla and one in the pons. In the medulla they are the dorsal respiratory group, and the ventral respiratory group. In the pons, the pontine respiratory group includes two areas known as the pneumotaxic centre and the apneustic centre. The respiratory centre is responsible for generating and maintaining the rhythm of respiration, and also of adjusting this in homeostatic response to physiological changes. The respiratory center receives input from chemoreceptors, mechanoreceptors, the cerebral cortex, and the hypothalamus in order to regulate the rate and depth of breathing. Input is stimulated by altered levels of oxygen, carbon dioxide, and blood pH, by hormonal changes relating to stress and anxiety from the hypothalamus, and also by signals from the cerebral cortex to give a conscious contro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperventilation
Hyperventilation is irregular breathing that occurs when the rate or tidal volume of breathing eliminates more carbon dioxide than the body can produce. This leads to hypocapnia, a reduced concentration of carbon dioxide dissolved in the blood. The body normally attempts to compensate for this homeostatically, but if this fails or is overridden, the blood pH will rise, leading to respiratory alkalosis. The symptoms of respiratory alkalosis include: dizziness, tingling in the lips, hands or feet, headache, weakness, fainting, and seizures. In extreme cases it may cause carpopedal spasms, a flapping and contraction of the hands and feet. Factors that may induce or sustain hyperventilation include: physiological stress, anxiety or panic disorder, high altitude, head injury, stroke, respiratory disorders such as asthma, pneumonia, or hyperventilation syndrome, cardiovascular problems such as pulmonary embolisms, anemia, an incorrectly calibrated medical respirator, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. It is a trace gas in Earth's atmosphere at 421 parts per million (ppm), or about 0.04% by volume (as of May 2022), having risen from pre-industrial levels of 280 ppm. Burning fossil fuels is the primary cause of these increased CO2 concentrations and also the primary cause of climate change.IPCC (2022Summary for policy makersiClimate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA Carbon dioxide is soluble in water and is found in groundwater, lakes, ice ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winters' Formula
Winters' formula, named after Dr. R.W. Winters, is a formula used to evaluate respiratory compensation when analyzing acid-base disorders in the presence of metabolic acidosis. It can be given as: P_ = (1.5 \times HCO_\sgn) + 8 \pm 2, where − is given in units of mEq/L and P will be in units of mmHg. Winters' formula gives an expected value for the patient's P; the patient's actual (measured) P is then compared to this. If the two values correspond, respiratory compensation is considered to be adequate. If the measured P is higher than the calculated value, there is also a primary respiratory acidosis. If the measured P is lower than the calculated value, there is also a primary respiratory alkalosis Respiratory alkalosis is a medical condition in which increased respiration elevates the blood pH beyond the normal range (7.35–7.45) with a concurrent reduction in arterial levels of carbon dioxide. This condition is one of the four primary dis .... References Res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Alkalosis
Metabolic alkalosis is a metabolic condition in which the pH of tissue is elevated beyond the normal range (7.35–7.45). This is the result of decreased hydrogen ion concentration, leading to increased bicarbonate, or alternatively a direct result of increased bicarbonate concentrations. The condition typically cannot last long if the kidneys are functioning properly. Signs and symptoms Mild cases of metabolic alkalosis often cause no symptoms. Typical manifestations of moderate to severe metabolic alkalosis include abnormal sensations, neuromuscular irritability, tetany, abnormal heart rhythms (usually due to accompanying electrolyte abnormalities such as low levels of potassium in the blood), coma, seizures, and temporary waxing and waning confusion. Causes The causes of metabolic alkalosis can be divided into two categories, depending upon urine chloride levels. Chloride-responsive (Urine chloride < 25 mEq/L) * Loss of hydrogen ions – Most often occurs via ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
