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Plethysmography, Whole Body
A plethysmograph is an instrument for measuring changes in volume within an organ or whole body (usually resulting from fluctuations in the amount of blood or air it contains). The word is derived from the Greek "plethysmos" (increasing, enlarging, becoming full), and "graphein" (to write). Organs studied Lungs Pulmonary plethysmographs are commonly used to measure the functional residual capacity (FRC) of the lungs—the volume in the lungs when the muscles of respiration are relaxed—and total lung capacity. In a traditional plethysmograph (or "body box"), the test subject, or patient, is placed inside a sealed chamber the size of a small telephone booth with a single mouthpiece. At the end of normal expiration, the mouthpiece is closed. The patient is then asked to make an inspiratory effort. As the patient tries to inhale (a maneuver which looks and feels like panting), the lungs expand, decreasing pressure within the lungs and increasing lung volume. This, in turn, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Plethysmography Male Subject
Body may refer to: In science * Physical body, an object in physics that represents a large amount, has mass or takes up space * Body (biology), the physical material of an organism * Body plan, the physical features shared by a group of animals * Human body, the entire structure of a human organism ** Dead body, cadaver, or corpse, a dead human body * (living) matter, see: Mind–body problem, the relationship between mind and matter in philosophy * Aggregates within living matter, such as inclusion bodies In arts and entertainment In film and television * Body (2015 Polish film), ''Body'' (2015 Polish film), a 2015 Polish film * Body (2015 American film), ''Body'' (2015 American film), a 2015 American film * Body (Wonder Showzen episode), "Body" (''Wonder Showzen'' episode), a 2006 episode of American sketch comedy television series ''Wonder Showzen'' * "Body", an episode of the Adult Swim television series, ''Off the Air (TV series), Off the Air'' In literature and publishin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaginal Photoplethysmography
Vaginal photoplethysmography (VPG, VPP) is a technique using light to measure the amount of blood in the walls of the vagina. The device that is used is called a vaginal photometer. Use The device is used to try to obtain an objective measure of a woman's sexual arousal. There is an overall poor correlation (r = 0.26) between women's self-reported levels of desire and their VPG readings. Instrument The instrument used in the procedure is called vaginal photometer. The device has a clear shell, inside of which is a light source and a photocell, which senses reflected light. The use of the device is done with the assumption that the more light that is scattered back, and that the photocell senses, the more blood is in the walls of the vagina. The output of the VPG can be filtered into two types of signals, which have different properties. The direct current signal is a measure of vaginal blood volume (VBV) and reflects the total blood volume in the vaginal tissues.Hatch, J. P. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Therapy
A respiratory therapist is a specialized healthcare professional, healthcare practitioner trained in Intensive care medicine, critical care and cardio-pulmonary medicine in order to work therapeutically with people who have acute critical conditions, Cardiovascular disease, cardiac and Respiratory disease, pulmonary disease. Respiratory therapists graduate from a college or university with a degree in respiratory therapy and have passed a national board certifying examination. The NBRC (National Board for Respiratory Care) is responsible for credentialing as a CRT (Certified Respiratory Therapist, certified respiratory therapist), or RRT (Registered Respiratory Therapist, registered respiratory therapist), The specialty certifications of respiratory therapy include: CPFT and RPFT (Certified or Registered Pulmonary Function Technologist), ACCS (Adult Critical Care Specialist), NPS (Neonatal/Pediatric Specialist), and SDS (Sleep disorder specialist, Sleep Disorder Specialist). Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measuring Instruments
A measuring instrument is a device to measure a physical quantity. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item under study and the referenced unit of measurement. Measuring instruments, and formal test methods which define the instrument's use, are the means by which these relations of numbers are obtained. All measuring instruments are subject to varying degrees of instrument error and measurement uncertainty. These instruments may range from simple objects such as rulers and stopwatches to electron microscopes and particle accelerators. Virtual instrumentation is widely used in the development of modern measuring instruments. Time In the past, a common time measuring instrument was the sundial. Today, the usual measuring instru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Equipment
A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assurance before regulating governments allow marketing of the device in their country. As a general rule, as the associated risk of the device increases the amount of testing required to establish safety and efficacy also increases. Further, as associated risk increases the potential benefit to the patient must also increase. Discovery of what would be considered a medical device by modern standards dates as far back as c. 7000 BC in Baluchistan where Neolithic dentists used flint-tipped drills and bowstrings. Study of archeology and Roman medical literature also indicate that many types of medical devices were in widespread use during the time of ancient Rome. In the United States it wasn't until the Federal Food, Drug, and Cosmetic Act (FD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Inductance Plethysmography
Respiratory inductance plethysmography (RIP) is a method of evaluating pulmonary ventilation by measuring the movement of the chest and abdominal wall. Accurate measurement of pulmonary ventilation or breathing often requires the use of devices such as masks or mouthpieces coupled to the airway opening. These devices are often both encumbering and invasive, and thus ill suited for continuous or ambulatory measurements. As an alternative RIP devices that sense respiratory excursions at the body surface can be used to measure pulmonary ventilation. According to a paper by Konno and Mead "the chest can be looked upon as a system of two compartments with only one degree of freedom each". Therefore, any volume change of the abdomen must be equal and opposite to that of the rib cage. The paper suggests that the volume change is close to being linearly related to changes in antero-posterior (front to back of body) diameter. When a known air volume is inhaled and measured with a spiromet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoplethysmograph
A photoplethysmogram (PPG) is an optically obtained plethysmogram that can be used to detect blood volume changes in the microvascular bed of tissue. A PPG is often obtained by using a pulse oximeter which illuminates the skin and measures changes in light absorption. A conventional pulse oximeter monitors the perfusion of blood to the dermis and subcutaneous tissue of the skin. With each cardiac cycle the heart pumps blood to the periphery. Even though this pressure pulse is somewhat damped by the time it reaches the skin, it is enough to distend the arteries and arterioles in the subcutaneous tissue. If the pulse oximeter is attached without compressing the skin, a pressure pulse can also be seen from the venous plexus, as a small secondary peak. The change in volume caused by the pressure pulse is detected by illuminating the skin with the light from a light-emitting diode (LED) and then measuring the amount of light either transmitted or reflected to a photodiode. Each c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optoelectronic Plethysmography
Optoelectronic plethysmography is a method to evaluate ventilation through an external measurement of the chest wall surface motion. A number of small reflective markers are placed on the thoraco-abdominal surface by hypoallergenic adhesive tape. A system for human motion analysis measures the three-dimensional coordinates of these markers and the enclosed volume is computed by connecting the points to form triangles. From optoelectronic plethysmography it is thus possible to obtain volume variations of the entire chest wall and its different compartments. The chest wall can be modeled as being composed of three different compartments: pulmonary rib cage, abdominal rib cage, and the abdomen. This model is the most appropriate for the study of chest wall kinematics in the majority of conditions, including exercise. It takes into consideration the fact that the lung- and diaphragm-apposed parts of the rib cage are exposed to substantially different pressures on their inner surface du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Sclerosis
Multiple (cerebral) sclerosis (MS), also known as encephalomyelitis disseminata or disseminated sclerosis, is the most common demyelinating disease, in which the insulating covers of nerve cells in the brain and spinal cord are damaged. This damage disrupts the ability of parts of the nervous system to transmit signals, resulting in a range of signs and symptoms, including physical, mental, and sometimes psychiatric problems. Specific symptoms can include double vision, blindness in one eye, muscle weakness, and trouble with sensation or coordination. MS takes several forms, with new symptoms either occurring in isolated attacks (relapsing forms) or building up over time (progressive forms). In the relapsing forms of MS, between attacks, symptoms may disappear completely, although some permanent neurological problems often remain, especially as the disease advances. While the cause is unclear, the underlying mechanism is thought to be either destruction by the immune system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronic Cerebrospinal Venous Insufficiency
Chronic cerebrospinal venous insufficiency (CCSVI or CCVI) is a term invented by Italian researcher Paolo Zamboni in 2008 to describe compromised flow of blood in the veins draining the central nervous system. Zamboni hypothesized that it might play a role in the cause or development of multiple sclerosis (MS). Zamboni also devised a surgical procedure which the media nicknamed a liberation procedure or liberation therapy, involving venoplasty or stenting of certain veins. Zamboni's ideas about CCSVI are very controversial, with significantly more detractors than supporters, and any treatments based on his ideas are considered experimental. There is no scientific evidence that CCSVI is related to MS, and there is no good evidence that the surgery helps MS patients. Zamboni's first published research was neither blinded nor did it have a comparison group. Zamboni also did not disclose his financial ties to Esaote, the manufacturer of the ultrasound specifically used in CCSVI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airway Resistance
In respiratory physiology, airway resistance is the resistance of the respiratory tract to airflow during inhalation and exhalation. Airway resistance can be measured using plethysmography. Definition Analogously to Ohm's Law: :R_ = \frac Where: : = P_ - P_A So: :R_ = \frac Where: *R_ = Airway Resistance *P = Pressure Difference driving airflow *P_ = Atmospheric Pressure *P_A = Alveolar Pressure *\dot V = Volumetric Airflow (not minute ventilation which, confusingly, may be represented by the same symbol) N.B. PA and \dot V change constantly during the respiratory cycle. Determinants of airway resistance There are several important determinants of airway resistance including: *The diameter of the airways *Whether airflow is laminar or turbulent Hagen–Poiseuille equation In fluid dynamics, the Hagen–Poiseuille equation is a physical law that gives the pressure drop in a fluid flowing through a long cylindrical pipe. The assumptions of the equation are that the flow is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirometry
Spirometry (meaning ''the measuring of breath'') is the most common of the pulmonary function tests (PFTs). It measures lung function, specifically the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled. Spirometry is helpful in assessing breathing patterns that identify conditions such as asthma, pulmonary fibrosis, cystic fibrosis, and COPD. It is also helpful as part of a system of health surveillance, in which breathing patterns are measured over time. Spirometry generates pneumotachographs, which are charts that plot the volume and flow of air coming in and out of the lungs from one inhalation and one exhalation. Indications Spirometry is indicated for the following reasons: * to diagnose or manage asthma * to detect respiratory disease in patients presenting with symptoms of breathlessness, and to distinguish respiratory from cardiac disease as the cause * to measure bronchial responsiveness in patients suspected of having asthma * to diagnose and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
