• Inhalation
  • in order to meet this requirement, the thoracic diaphragm has a tendency to lower to a greater extent during inhalation, which in turn causes an increase in lung volume. (wikipedia.org)
  • The most common clinical features of IPF include the following: Age over 50 years Dry, non-productive cough on exertion Progressive exertional dyspnea (shortness of breath with exercise) Dry, inspiratory bibasilar "velcro-like" crackles on auscultation (a crackling sound in the lungs during inhalation similar to Velcro being torn apart slowly, heard with a stethoscope). (wikipedia.org)
  • Vital capacity (VC) is the maximum amount of air a person can expel from the lungs after a maximum inhalation. (wikipedia.org)
  • Thorax
  • The gas pressure (P) needed to keep equilibrium between the collapsing force of surface tension (γ) and the expanding force of gas in an alveolus of radius r is expressed by the law of Laplace: P = 2 γ r {\displaystyle P={\frac {2\gamma }{r}}} Compliance is the ability of lungs and thorax to expand. (wikipedia.org)
  • Compared to the tissue conductivities of most other soft tissues within the human thorax, lung tissue conductivity is approximately five-fold lower, resulting in high absolute contrast. (wikipedia.org)
  • Diseases
  • Institute of Tuberculosis and Lung Diseases, Warsaw, Poland. (biomedsearch.com)
  • Despite aggressive public health initiatives aimed at discouraging the use of cigarettes, smoking-related lung diseases remain a significant cause of disability and death in the United States. (clinicaltrials.gov)
  • The results (in particular FEV1/FVC and FRC) can be used to distinguish between restrictive and obstructive pulmonary diseases: Lung capacity can be expanded through flexibility exercises such as yoga, breathing exercises, and physical activity. (wikipedia.org)
  • There is some evidence that viral infections may be associated with idiopathic pulmonary fibrosis and other fibrotic lung diseases. (wikipedia.org)
  • The pulmonologist begins the diagnostic process with a general review focusing on: hereditary diseases affecting the lungs (cystic fibrosis, alpha 1-antitrypsin deficiency) exposure to toxins (tobacco smoke, asbestos, exhaust fumes, coal mining fumes) exposure to infectious agents (certain types of birds, malt processing) an autoimmune diathesis that might predispose to certain conditions (pulmonary fibrosis, pulmonary hypertension) Physical diagnostics are as important as in the other fields of medicine. (wikipedia.org)
  • Brazilians use it internally to treat diseases of the lungs. (wikipedia.org)
  • Alveolar
  • VEGF expression was significantly reduced in the lung, particularly in the alveolar septal cells. (medsci.org)
  • It is hypothesized that the initial or repetitive injury in IPF occurs to the lung cells, called alveolar epithelial cells (AECs, pneumocytes), which line the majority of the alveolar surface. (wikipedia.org)
  • alveoli
  • This also helps all alveoli in the lungs expand at the same rate, as one that expands more quickly will experience a large rise in surface tension slowing its rate of expansion. (wikipedia.org)
  • This is due to the fact that a high compliant lung results in many collapsed alveoli which makes inflation difficult. (wikipedia.org)
  • Gas exchange in the lungs occurs in millions of small air sacs called alveoli in mammals and reptiles, but atria in birds. (wikipedia.org)
  • A system such as this creates dead space, a volume of air (about 150 ml in the adult human) that fills the airways after exhalation and is breathed back into the alveoli before environmental air reaches them. (wikipedia.org)
  • Residual Volume
  • Determination of the residual volume is more difficult as it is impossible to "completely" breathe out. (wikipedia.org)
  • Therefore, measurement of the residual volume has to be done via indirect methods such as radiographic planimetry, body plethysmography, closed circuit dilution (including the helium dilution technique) and nitrogen washout. (wikipedia.org)
  • Standard errors in prediction equations for residual volume have been measured at 579 mL for men and 355 mL for women, while the use of 0.24*FVC gave a standard error of 318 mL. (wikipedia.org)
  • hysteresis
  • This difference in inflation and deflation volumes at a given pressure is called hysteresis and is due to the air-water surface tension that occurs at the beginning of inflation. (wikipedia.org)
  • spirometer
  • This technique is based on the assumptions that a known volume and concentration of helium in air begin in the closed spirometer, that the patient has no helium in their lungs, and that an equilibration of helium can occur between the spirometer and the lungs. (wikipedia.org)
  • oxygen
  • This test allows the doctor to estimate how well the lungs move oxygen from the air into the bloodstream. (stlukes-stl.com)
  • the Himalayas) that person can develop a condition called altitude sickness because their lungs remove adequate amounts of carbon dioxide but they do not take in enough oxygen. (wikipedia.org)
  • Some people may benefit from long-term oxygen therapy or lung transplantation. (wikipedia.org)
  • The technique is based on the assumptions that the nitrogen concentration in the lungs is 78% and in equilibrium with the atmosphere, that the patient inhales 100% oxygen and that the oxygen replaces all of the nitrogen in the lungs. (wikipedia.org)
  • restrictive
  • This pattern of decline confirmed a restrictive pattern with an average loss of 2 percent per year of total lung capacity. (bio-medicine.org)
  • Compliance decreases in the following cases: Supine position Laparoscopic surgical interventions Severe restrictive pathologies Chronic restrictive pathologies Hydrothorax Pneumothorax High standing of a diaphragm Acute asthma attacks [Increased compliance also occurs, for an unclear reason] Lung compliance at the US National Library of Medicine Medical Subject Headings (MeSH) Compliance Nikischin W, Gerhardt T, Everett R, Bancalari E (1998). (wikipedia.org)
  • In restrictive lung disease the vital capacity is decreased. (wikipedia.org)
  • Adult
  • The average total lung capacity of an adult human male is about 6 litres of air. (wikipedia.org)
  • A typical adult human spirogram with the names given to the various excursions in volume the lungs can undergo is illustrated below (Fig. 3): Not all the air in the lungs can be expelled during maximally forced exhalation. (wikipedia.org)
  • pressures
  • To test this hypothesis, we studied four experienced normal subjects during fatiguing breathing tasks performed over a range of pressures and flows and at two different lung volumes. (biomedsearch.com)
  • rate of decline
  • Non-specific bronchial hyperresponsiveness (NSBH) is a known predictor of accelerated rate of decline in lung function in smokers. (bmj.com)
  • Based on these associations, we hypothesised that ADRB2 polymorphisms would be associated with NSBH and BDR as well as an accelerated rate of decline in lung function among smokers. (bmj.com)
  • Contrary to our hypothesis, no ADRB2 allele or haplotype was associated with NSBH, BDR, or rate of decline in lung function. (bmj.com)
  • Heterozygosity at position 27 may be protective against an accelerated rate of decline in lung function. (bmj.com)
  • The polymorphism at position 16 does not contribute to the rate of decline in lung function, measures of NSBH, or BDR in smokers. (bmj.com)
  • Using statistical modeling, we are able to predict the rate of decline of lung function. (bio-medicine.org)
  • Compliance
  • the decrease in dynamic lung compliance plays a definite but less important role. (biomedsearch.com)
  • Lung compliance is defined as the volume change per unit of pressure change across the lung. (wikipedia.org)
  • Pulmonary surfactant thus greatly reduces surface tension, increasing compliance allowing the lung to inflate much more easily, thereby reducing the work of breathing. (wikipedia.org)
  • Static lung compliance is the change in volume for any given applied pressure. (wikipedia.org)
  • Dynamic lung compliance is the compliance of the lung at any given time during actual movement of air. (wikipedia.org)
  • Low compliance indicates a stiff lung (one with high elastic recoil) and can be thought of as a thick balloon - this is the case often seen in fibrosis. (wikipedia.org)
  • Compliance is highest at moderate lung volumes, and much lower at volumes which are very low or very high. (wikipedia.org)
  • that is, the compliance is different on inspiration and expiration for identical volumes. (wikipedia.org)
  • Dynamic compliance is always lower than or equal to static lung compliance because PIP − PEEP is always greater than Pplat − PEEP. (wikipedia.org)
  • Low compliance indicates a stiff lung and means extra work is required to bring in a normal volume of air. (wikipedia.org)
  • Stroke Volume
  • assuming a heart rate of 70 beats/min, the stroke volume would be approximately 70 mL. (wikipedia.org)
  • 2D measurement of the diameter (d) of the aortic annulus allows calculation of the flow cross-sectional area (CSA), which is then multiplied by the VTI of the Doppler flow profile across the aortic valve to determine the flow volume per beat (stroke volume, SV). (wikipedia.org)
  • clinical
  • Differences such as measurement technique, equipment calibration, occupational factors, and selection bias must be considered when reference values from published reports are used for clinical or epidemiological purposes. (biomedsearch.com)
  • To determine the patterns of loss of lung function, the researchers analyzed 1,357 lung function results that were completed between January 1989 and January 2005 from 413 children with sickle cell disease (SCD) during routine sickle cell clinical visits. (bio-medicine.org)
  • The group suggested that non-invasive technique measurements were of sufficient accuracy to be tried in clinical practice. (wikipedia.org)
  • compute
  • Online calculators are available that can compute predicted lung volumes, and other spirometric parameters based on a patient's age, height, weight, and ethnic origin for many reference sources. (wikipedia.org)
  • The digital information was used to compute automatically the volume of the trunk and the position of any point on its surface and its cross-sectional shape at any level. (wikipedia.org)
  • decreases
  • 1 Animal and human studies have demonstrated that the administration of recombinant human Cu-Zn superoxide dismutase (rhSOD) decreases acute and chronic lung injury from hyperoxia. (ispub.com)
  • Assess
  • Movements of the grid are viewed by two digital cameras, digitalised, and processed to form a 3D model and can be interrogated to assess lung function. (wikipedia.org)
  • decline
  • However, there was a significant negative association between heterozygosity at position 27 and a fast decline in lung function (adjusted odds ratio 0.56, 95% CI 0.40 to 0.78, p=0.0007). (bmj.com)
  • We expected that children with sickle cell disease would show greater loss of lung function than other children, but this had never been quantified, nor was the pattern of decline clear. (bio-medicine.org)