China
Africa
Explore chapters and articles related to this topic
Diagnostic Devices
Published in Laurence J. Street, Introduction to Biomedical Engineering Technology, 2023
Simple spirometers consist of a breathing tube for the patient, and a bellows or piston mechanism that can move when air from the patient’s breathing enters or leaves the system. The movement can be indicated by a pointer and calibrated strip, or by a pen moving against a chart recorder or drum recorder.
Pulmonary Function Tests
Published in Robert B. Northrop, Non-Invasive Instrumentation and Measurement in Medical Diagnosis, 2017
Spirometers basically measure the respiratory volumes, or in the case of modern units, respiratory volume flow rate which is integrated to determine the volume. Some of the common parameters used in spirometry are: FVC (forced vital capacity): This is the total volume of air a patient can exhale after a maximum effort inspiration. Patients with restrictive lung disease (RLD) have a lower FVC than do patients with obstructive lung disease (OLD).FEV1 (forced expiratory volume in 1 s) (also, FEV1/2): The volume of air expired in the first second following the beginning of maximum expiratory effort. FEV1 is reduced from normal in both OLDs and RLDs, but for different reasons; increased airway resistance in OLD, and decreased vital capacity in RLD.FEV1/FVC: This ratio is about 0.7 in healthy subjects. It can be as low as 0.2–0.3 in patients with OLD. Patients with RLD have near-normal ratios.FEF (25%–75%) (forced mid-expiratory flow rate): The average rate of flow during the middle of the FVC maneuver.Reduced in both OLD and RLD.DLCO (diffusion capacity of the lung for carbon monoxide): The poison gas, CO, can be used to measure the diffusion capacity of the alveoli. The diffusion capacity of the lung is decreased in parenchymal diseases, such as emphysema. It is normal in asthma. (Other gases can be used.)FRC (functional residual capacity): The volume of air remaining in the lungs and trachea after an exhale in normal breathing.RV (residual volume): The volume of air left in the lungs after a maximum FVC exhale. It is the “dead space” of the respiratory system; mostly combined trachea and bronchial tube volumes. It cannot be measured directly.TV (tidal volume): The volume exchanged in normal, relaxed breathing.AV (alveolar volume): Total volume of all the minute alveoli in the lung parenchyma.
Acute responses to sprint-interval and continuous exercise in adults with and without exercise-induced bronchoconstriction
Published in Journal of Sports Sciences, 2019
Joshua Good, Eric Viana, Kirsten A Burgomaster, Shilpa Dogra
Throughout each session, participants completed lung function measurements using a handheld spirometer (EasyOne diagnostic spirometer, ndd Medizintechnik AG, Switzerland). Lung function measurements assessed were FEV1, and FEV1% predicted based on the Third National Health and Nutrition Examination Survey (NHANES III) reference values (NCHS, 2001). For baseline measurements, participants performed a minimum of three trials, in accordance with the ATS Guidelines (Miller et al., 2005). For measurements during the SIE and CE sessions and following all sessions, two acceptable trials were performed. During SIE, spirometry was performed 3 min following each sprint (minutes 3.5, 8.5, 13.5, and 18.5) and at corresponding time points during CE to assess the EIBC response during exercise. Following all sessions, spirometry was performed at 1, 5, 10, 15, and 20 min post-session. The decline in FEV1 was calculated as follows: