if you want to remove an article from website contact us from top.

    what device measures the volume and flow of air during inspiration and expiration


    Guys, does anyone know the answer?

    get what device measures the volume and flow of air during inspiration and expiration from EN Bilgi.

    Respiratory Volumes and Capacities

    Respiratory Volumes and Capacities

    Under normal conditions, the average adult takes 12 to 15 breaths a minute. A breath is one complete respiratory cycle that consists of one inspiration and one expiration.

    An instrument called a spirometer is used to measure the volume of air that moves into and out of the lungs, and the process of taking the measurements is called spirometry. Respiratory (pulmonary) volumes are an important aspect of pulmonary function testing because they can provide information about the physical condition of the lungs.

    Respiratory capacity (pulmonary capacity) is the sum of two or more volumes.

    Factors such as age, sex, body build, and physical conditioning have an influence on lung volumes and capacities. Lungs usually reach their maximumin capacity in early adulthood and decline with age after that.

    « Previous (Mechanics of Ventilation)

    Next (Conducting Passages) »

    Source : training.seer.cancer.gov


    Wiki Loves Earth in Turkey photography contest has started!

    Visit WLE 2022 and upload your photos of natural monuments and Win!


    From Wikipedia, the free encyclopedia

    Jump to navigation Jump to search Spirometer

    Spirometer test

    Purpose measuring the volume of air inspired and expired by the lungs

    A spirometer is an apparatus for measuring the volume of air inspired and expired by the lungs. A spirometer measures ventilation, the movement of air into and out of the lungs. The spirogram will identify two different types of abnormal ventilation patterns, obstructive and restrictive. There are various types of spirometers that use a number of different methods for measurement (pressure transducers, ultrasonic, water gauge).


    1 Pulmonary function tests

    2 Reasons for testing

    3 History

    3.1 Early development

    3.2 Nineteenth century

    3.3 Twentieth century

    3.4 Interpreting Spirometry

    3.4.1 Standard Guidelines

    3.4.2 Motivations 3.4.3 Implications

    3.4.4 Altering interpretations

    4 Types of spirometer

    4.1 Whole body plethysmograph

    4.2 Pneumotachometer

    4.3 Fully electronic spirometer

    4.4 Incentive spirometer

    4.5 Peak flow meter

    4.6 Windmill-type spirometer

    5 See also 6 Footnotes 7 Further reading

    Pulmonary function tests[edit]

    Main article: Pulmonary function testing

    A spirometer is the main piece of equipment used for basic Pulmonary Function Tests (PFTs). Lung diseases such as asthma, bronchitis, and emphysema may be ruled out from the tests. In addition, a spirometer often is used for finding the cause of shortness of breath, assessing the effect of contaminants on lung function, the effect of medication, and evaluating progress for disease treatment.[1]

    Reasons for testing[edit]

    Diagnose certain types of lung disease (such as COVID-19, bronchitis, and emphysema)

    Find the cause of shortness of breath

    Measure whether exposure to chemicals at work affects lung function

    Check lung function before someone has surgery

    Assess the effect of medication

    Measure progress in disease treatment


    A simple float spirometer being used in a high school science demonstration

    Early development[edit]

    The earliest attempt to measure lung volume can be dated back to the period A.D. 129–200. Claudius Galen, a Roman physician and philosopher, did a volumetric experiment on human ventilation. He had a child breathe in and out of a bladder and found that the volume did not change. The experiment proved inconclusive.[2]

    1681, Borelli tried to measure the volume of air inspired in one breath. He assembled a cylindrical tube partially filled with water, with an open water source entering the bottom of the cylinder. He occluded his nostrils, inhaled through an outlet at the top of the cylinder and measured the volume of air displaced by water. Nowadays, this technique is very important in determining parameters of lung volume.[2]

    Nineteenth century[edit]

    1813, Kentish, E. used a simple "Pulmometer" to study the effect of diseases on pulmonary lung volume. He used an inverted graduated bell jar standing in water, with an outlet at the top of the bell jar controlled by a tap. The volume of air was measured in units of pints.[2]

    1831, Thackrah, C. T. described a "Pulmometer" similar to that of Kentish. He portrayed the device as a bell jar with an opening for the air to enter from below. There was no correction for pressure. Therefore, the spirometer not only measured the respiratory volume, but also the strength of the respiratory muscles.[2]

    1845, Vierordt in his book entitled "Physiologie des Athmens mit besonderer Rücksicht auf die Auscheidung der Kohlensäure" discussed his interest in measuring the volume of expiration accurately. He also completed accurate measures of other volume parameters by using his "Expirator". Some of the parameters he described are used today, including residual volume and vital capacity.[2]

    1846 The water spirometer measuring vital capacity was developed by a surgeon named John Hutchinson. He invented a calibrated bell inverted in water, which was used to capture the volume of air exhaled by a person. Hutchinson published his paper about his water spirometer and the measurements he had taken from more than 4,000 subjects,[2] describing the direct relationship between vital capacity and height and the inverse relationship between vital capacity and age. He also showed that vital capacity does not relate to weight at any given height. Hutchinson is regarded as the inventor of vital capacity because he found that with every inch of height vital capacity increased by eight cubic inches.[3] He also used his machine for the prediction of premature mortality. He coined the term 'vital capacity', which was claimed as a powerful prognosis for heart disease by the Framingham study. He believed that his machine should be used for actuarial predictions for companies selling life insurance.[4]

    Source : en.wikipedia.org



    It too is a spirometer that is attached directly to a smartphone, and it also generates charts to help patients and clinicians monitor changes in peak flow rate and take appropriate action.

    From: The Transformative Power of Mobile Medicine, 2019

    Related terms:

    Lung VolumesSpirometryVital CapacityChronic Obstructive Pulmonary DiseaseForced Expiratory VolumeForced Vital CapacityResidual Volume

    View all Topics

    Lung Volumes and Airway Resistance

    Joseph Feher, in Quantitative Human Physiology (Second Edition), 2017


    Spirometers can measure three of four lung volumes, inspiratory reserve volume, tidal volume, expiratory reserve volume, but cannot measure residual volume. Four lung capacities are also defined: inspiratory capacity, vital capacity, functional residual capacity, and the total lung capacity. Pulmonary ventilation is the product of tidal volume and respiratory frequency. The maximum voluntary ventilation is the maximum air that can be moved per minute. Spirometry also provides a measure of airway resistance by use of the forced expiratory volume test. The clinical spirogram presents the forced vital capacity differently. In laminar flow, pressure necessary to drive flow increases linearly with the flow. In turbulent flow, pressure increases with the square of the flow. The Reynolds number is used to estimate whether flow is laminar or turbulent. Airway resistance also increases inversely with lung volume because stretch of the lungs opens airways. Dynamic compression limits flow at high expiratory effort.

    View chapter Purchase book

    Pulmonary Function Testing

    Bruce H. Culver, in Clinical Respiratory Medicine (Fourth Edition), 2012

    Measurement by Helium Dilution

    A spirometer is prepared that contains a known volume and concentration of an inert gas, typically 10% helium (Figure 9-3). While the subject breathes through a mouthpiece with nose clipped, a valve is turned at end-tidal exhalation to connect the airway to this closed system. As normal tidal breathing continues over the course of a few minutes, the gas in the subject's lung equilibrates with gas in the spirometer, and the helium concentration, which is continuously monitored, falls to a new, lower, steady-state level. Carbon dioxide is removed from the closed system by soda lime absorption, and a low flow of oxygen is added to compensate for the subject's ongoing oxygen consumption by keeping the mixing chamber or spirometer volume constant. The ratio of the initial to the final concentration of helium allows calculation of the unknown volume (FRC) added to the system. A continuous tracing of the spirogram, including a maximum inspiratory and expiratory effort, allows calculation of the subdivisions of lung volume, and correction for any offset from the relaxed FRC at the moment the valve was opened to start the test.

    View chapter Purchase book

    Lung function testing

    Roger Hainsworth, in Foundations of Anesthesia (Second Edition), 2006

    Spirometer types

    A spirometer is a device for measuring the volumes of air that can be breathed. If the volume signal is differentiated, either electronically or by manual measurements from the volume–time traces, spirometers can also be used to derive the gas flow rates. The most accurate type of spirometer is the water-sealed bell spirometer. This is an inverted bell, sealed under water and counterbalanced (Fig. 50.1). Assuming the bell is a perfect cylinder, the displacement of the counterweight and the attached pen is directly related to the change in volume. If the recording kymograph is set to move rapidly, it is possible to determine the rate of change of volume and hence the expiratory and inspiratory flow rates.

    Although this type of spirometer is inherently very simple, there are a number of precautions relating to its use. Generally, the bell will have a diameter to match the calibration on the recording device or the supplied paper. Nevertheless, a check should be made by injecting known volumes of gas. The readout gives volumes at ambient pressure and temperature, although the volumes actually within the lung are at body temperature and atmospheric pressure saturated with water vapor (BTPS). This is usually about 10% greater than the measured volume, and should be corrected accordingly by applying the gas laws or by the use of appropriate tables.

    For accurate measurements of high flow rates the spirometer bell and counterweight should have minimum inertia, and bells constructed of lightweight plastic materials are preferred. Another problem may be leaks in the system; these can easily be checked by occluding the connecting tubing and applying a weight on the top of the bell. The bell should not continue to move.

    Water-filled spirometers have the disadvantages that they are heavy, subject to spillage, and that electronic outputs are not directly obtained. In attempts to solve these problems, various other devices have been introduced. One widely used device that is convenient and readily transported is the bellows or wedge spirometer. As gas moves into the bellows, the bellows move about the hinge and a pointer tracks over moving paper to define the expiratory volume–time trace. It does not, however, record tidal volume or inspiratory volumes. Bellows spirometers need to be carefully calibrated, with particular attention paid to the linearity of the readings.

    Source : www.sciencedirect.com

    Do you want to see answer or more ?
    James 10 month ago

    Guys, does anyone know the answer?

    Click For Answer