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Vasoactivity
A vasoactive substance is an endogenous agent or pharmaceutical drug that has the effect of either increasing or decreasing blood pressure and/or heart rate through its vasoactivity, that is, vascular activity (effect on blood vessels). By adjusting vascular compliance and vascular resistance, typically through vasodilation and vasoconstriction, it helps the body's homeostatic mechanisms (such as the renin–angiotensin system) to keep hemodynamics under control. For example, angiotensin, bradykinin, histamine, nitric oxide, and vasoactive intestinal peptide are important endogenous vasoactive substances. Vasoactive drug therapy is typically used when a patient has the blood pressure and heart rate monitored constantly. The dosage is typically titrated (adjusted up or down) to achieve a desired effect or range of values as determined by competent clinicians. Vasoactive drugs are typically administered using a volumetric infusion device (IV pump). This category of drugs requir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compliance (physiology)
Compliance is the ability of a hollow organ (vessel) to distend and increase volume with increasing transmural pressure or the tendency of a hollow organ to resist recoil toward its original dimensions on application of a distending or compressing force. It is the reciprocal of "elastance", hence elastance is a measure of the tendency of a hollow organ to recoil toward its original dimensions upon removal of a distending or compressing force. Blood vessels The terms elastance and compliance are of particular significance in cardiovascular physiology and respiratory physiology. In compliance, an increase in volume occurs in a vessel when the pressure in that vessel is increased. The tendency of the arteries and veins to stretch in response to pressure has a large effect on perfusion and blood pressure. This physically means that blood vessels with a higher compliance deform easier than lower compliance blood vessels under the same pressure and volume conditions. Venous complian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endogenous
Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, estradiol is an endogenous estrogen hormone produced within the body, whereas ethinylestradiol is an exogenous synthetic estrogen, commonly used in birth control pills Oral contraceptives, abbreviated OCPs, also known as birth control pills, are medications taken by mouth for the purpose of birth control. Female Two types of female oral contraceptive pill, taken once per day, are widely available: * The combi .... References External links *{{Wiktionary-inline, endogeny Biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monitoring (medicine)
In medicine, monitoring is the observation of a disease, condition or one or several medical parameters over time. It can be performed by continuously measuring certain parameters by using a medical monitor (for example, by continuously measuring vital signs by a bedside monitor), and/or by repeatedly performing medical tests (such as blood glucose monitoring with a glucose meter in people with diabetes mellitus). Transmitting data from a monitor to a distant monitoring station is known as telemetry or biotelemetry. Classification by target parameter Monitoring can be classified by the target of interest, including: * Cardiac monitoring, which generally refers to continuous electrocardiography with assessment of the patients condition relative to their cardiac rhythm. A small monitor worn by an ambulatory patient for this purpose is known as a Holter monitor. Cardiac monitoring can also involve cardiac output monitoring via an invasive Swan-Ganz catheter. * Hemodynamic m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choosing Wisely
Choosing Wisely is a United States-based health educational campaign, led by the ABIM Foundation ( American Board of Internal Medicine), about unnecessary health care. The campaign identifies over 500 tests and procedures and encourages doctors and patients to discuss, research, and possibly get second opinions, before proceeding with them. To conduct the campaign, the ABIM Foundation asks medical specialty societies to make five to ten recommendations for preventing overuse of a treatment in their field. The foundation then publicizes this information, and the medical specialty societies disseminate it to their members. The campaign has garnered both praise and criticism, and some of its ideas have spread to other countries. It does not include evaluation of its effects on costs, on discussions or on medical outcomes. Some doctors have said they lack time for the recommended discussions. History In 2002 the ABIM Foundation published ''Medical professionalism in the new millen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Disease
Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bronchioles, alveoli, pleurae, pleural cavity, the nerves and muscles of respiration. Respiratory diseases range from mild and self-limiting, such as the common cold, influenza, and pharyngitis to life-threatening diseases such as bacterial pneumonia, pulmonary embolism, tuberculosis, acute asthma, lung cancer, and severe acute respiratory syndromes, such as COVID-19. Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease. The study of respiratory disease is known as pulmonology. A physician who specializes in respiratory disease is known as a pulmonologist, a chest medicine specialist, a respiratory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxemia
Hypoxemia is an abnormally low level of oxygen in the blood. More specifically, it is oxygen deficiency in arterial blood. Hypoxemia has many causes, and often causes hypoxia as the blood is not supplying enough oxygen to the tissues of the body. Definition ''Hypoxemia'' refers to the low level of oxygen in blood, and the more general term ''hypoxia'' is an abnormally low oxygen content in any tissue or organ, or the body as a whole. Hypoxemia can cause hypoxia (hypoxemic hypoxia), but hypoxia can also occur via other mechanisms, such as anemia. Hypoxemia is usually defined in terms of reduced partial pressure of oxygen (mm Hg) in arterial blood, but also in terms of reduced content of oxygen (ml oxygen per dl blood) or percentage saturation of hemoglobin (the oxygen-binding protein within red blood cells) with oxygen, which is either found singly or in combination. While there is general agreement that an arterial blood gas measurement which shows that the partial pressure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart Failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, and leg swelling. The shortness of breath may occur with exertion or while lying down, and may wake people up during the night. Chest pain, including angina, is not usually caused by heart failure, but may occur if the heart failure was caused by a heart attack. The severity of the heart failure is measured by the severity of symptoms during exercise. Other conditions that may have symptoms similar to heart failure include obesity, kidney failure, liver disease, anemia, and thyroid disease. Common causes of heart failure include coronary artery disease, heart attack, high blood pressure, atrial fibrillation, valvular heart disease, excessive alcohol consumption, infection, and cardiomyopathy. These cause heart failure by alterin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphodiesterase Inhibitor
A phosphodiesterase inhibitor is a drug that blocks one or more of the five subtypes of the enzyme phosphodiesterase (PDE), thereby preventing the inactivation of the intracellular second messengers, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) by the respective PDE subtype(s). The ubiquitous presence of this enzyme means that non-specific inhibitors have a wide range of actions, the actions in the heart, and lungs being some of the first to find a therapeutic use. History The different forms or subtypes of phosphodiesterase were initially isolated from rat brains in the early 1970s and were soon afterward shown to be selectively inhibited in the brain and in other tissues by a variety of drugs. The potential for selective phosphodiesterase inhibitors as therapeutic agents was predicted as early as 1977 by Weiss and Hait. This prediction meanwhile has proved to be true in a variety of fields. Classification Nonselective PDE inhibitors Methy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostanoid
Prostanoids are active lipid mediators that regulate inflammatory response. Prostanoids are a subclass of eicosanoids consisting of the prostaglandins (mediators of inflammatory and anaphylactic reactions), the thromboxanes (mediators of vasoconstriction), and the prostacyclins (active in the resolution phase of inflammation). Prostanoids are seen to target NSAIDS which allow for therapeutic potential. Prostanoids are present within areas of the body such as the gastrointestinal tract, urinary tract, respiratory and cardiology systems, reproductive tract and vascular system. Prostanoids can even be seen with aid to the water and ion transportation within cells. Prostanoids help release prostaglandins upon activation, receptors may open possibilities for treatments within different systems. History Prostanoids were discovered through biological research studies conducted in the 1930s. The first discovery was seen through semen by a Swedish Physiologist Ulf von Euler, who assu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenergic Agonist
An adrenergic agonist is a drug that stimulates a response from the adrenergic receptors. The five main categories of adrenergic receptors are: α1, α2, β1, β2, and β3, although there are more subtypes, and agonists vary in specificity between these receptors, and may be classified respectively. However, there are also other mechanisms of adrenergic agonism. Epinephrine and norepinephrine are endogenous and broad-spectrum. More selective agonists are more useful in pharmacology. An ' agent is a drug, or other substance, which has effects similar to, or the same as, epinephrine (adrenaline). Thus, it is a kind of sympathomimetic agent. Alternatively, it may refer to something which is susceptible to epinephrine, or similar substances, such as a biological receptor (specifically, the adrenergic receptors). Receptors Directly acting adrenergic agonists act on adrenergic receptors. All adrenergic receptors are G-protein coupled, activating signal transduction pathways. The G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endothelin
Endothelins are peptides with receptors and effects in many body organs. Endothelin constricts blood vessels and raises blood pressure. The endothelins are normally kept in balance by other mechanisms, but when overexpressed, they contribute to high blood pressure (hypertension), heart disease, and potentially other diseases. Endothelins are 21-amino acid vasoconstricting peptides produced primarily in the endothelium having a key role in vascular homeostasis. Endothelins are implicated in vascular diseases of several organ systems, including the heart, lungs, kidneys, and brain. As of 2018, endothelins remain under extensive basic and clinical research to define their roles in several organ systems. Etymology Endothelins derived the name from their isolation in cultured endothelial cells. Isoforms There are three isoforms of the peptide (identified as ET-1, -2, -3), each encoded by a separate gene, with varying regions of expression and binding to at least four known e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
