In summary, argon deaeration decreases the concentration and the variability of exhaled breath condensate partial pressure of CO2, but there is always some remaining CO2 that may still be a confounding factor in pH assessment. CO2 content has a marked influence on exhaled breath condensate pH and, since exhaled breath condensate partial pressure of CO2 varies even after deaeration, it leaves so...

Breath holding time is the time taken by the subject to hold his breath as long as he can. During voluntary breath holding, tissues continue to utilize oxygen and liberate carbon dioxide. Therefore during breath holding arterial pO2 falls and pCO2 rises. Since both these factors are powerful respiratory stimulants, a point is reached where the respiratory drive becomes so strong that the person...

Early detection of lung cancer is a key factor for increasing the survival rates of lung cancer patients. The analysis of exhaled breath is promising as a noninvasive diagnostic tool for diagnosis of lung cancer. We demonstrate the quantitative analysis of carbonyl volatile organic compounds (VOCs) and identification of lung cancer VOC markers in exhaled breath using unique silicon microreactor...

Helicobacter pylori infection is supposed to be one of the major causes of digestive and other diseases. Among a lot of invasive and non-invasive methods for its detection, none is ideal. The aim is an assessment of the Helicobacter pylori infection in the stomach using breath test and comparison to other diagnostic methods, as well as following up the effects of therapy. In 17 patients with di...

BACKGROUND Spectral characteristics of breath sounds in asthma and chronic obstructive pulmonary disease (COPD) have not previously been compared, although the structural differences in these disorders might be reflected in breath sounds. METHODS Flow standardised inspiratory breath sounds in patients with COPD (n = 17) and stable asthma (n = 10) with significant airways obstruction and in co...

AIMS The breath group can serve as a functional unit to define temporal and fundamental frequency (f0) features in continuous speech. These features of the breath group are determined by the physiologic, linguistic, and cognitive demands of communication. Reading and spontaneous speech are two speaking tasks that vary in these demands and are commonly used to evaluate speech performance for res...

The urge to breathe, as stimulated by hypercapnia, is generally considered to cause a breath-hold diver to end the breath-hold, and pre-breath hold hyperventilation has been suggested to cause hypoxic loss of consciousness (LOC) due to the reduced urge to breathe. Competitors hyperventilate before "Static Apnea", yet only 10% surface with symptoms of hypoxia such as loss of motor control (LMC) ...

The organic constituents of exhaled human breath are representative of blood-borne concentrations through gas exchange in the blood/breath interface in the lungs. The presence of specific compounds can be an indicator of recent exposure or represent a biological response of the subject. For volatile organic compounds (VOCs), sampling and analysis of breath is preferred to direct measurement fro...

The ratio of blood-alcohol concentration (BAC) to breath-alcohol concentration (BrAC) was determined for 799 individuals apprehended for driving under the influence of alcohol (DUI) in Sweden. The BrAC was determined with an infrared analyzer (Intoxilyzer 5000S) and venous BAC was measured by headspace gas chromatography. The blood samples were always taken after the breath tests were made and ...

The lactose hydrogen breath test is a commonly used, non-invasive method for the detection of lactose malabsorption and is based on an abnormal increase in breath hydrogen (H₂) excretion after an oral dose of lactose. We use a combined (13)C/H₂ lactose breath test that measures breath (13)CO₂ as a measure of lactose digestion in addition to H₂ and that has a better sensitivity and specificity t...