Automatic end-expiratory air sampling device for breath hydrogen test in infants

Yeung, Ching‐Hei; Wong, F. H. W.; Tam, A. Y. C.; Ma, Yangyang; Kwan, Haowen; Fung, K. W.

doi:10.1016/0140-6736(91)90746-c

Cited by 6 publications

(4 citation statements)

References 20 publications

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“…The end tidal carbon monoxide (ETCO) was measured using the similar device as in earlier studies. [7,8] The ETCO obtained was shown to correlate well with the percentage HbCO in the present study. This is consistent with another study using a different collection method as reported recently.…”

supporting

confidence: 78%

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End tidal carbon monoxide concentration in childhood haemolytic disorders

Chan

Lau

Yeung

1998

J Paediatrics Child Health

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supporting

confidence: 78%

“…We have developed a simple method for collection of the end tidal breath from neonates[7] and children[8] (Fig. 1).…”

mentioning

confidence: 99%

End tidal carbon monoxide concentration in childhood haemolytic disorders

Chan

Lau

Yeung

1998

J Paediatrics Child Health

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“…Several methods have been proposed and all depend on monitoring either physical or chemical characteristics of the exhaled gas directly during breathing. Common or possible parameters for controlled sampling are endogenous carbon dioxide [27] or specific VOCs such as acetone [20], gas volume or flow [28], e.g. spirometry, gas humidity [29] and physically 'slicing' exhaled fractions, e.g.…”

Section: Selecting Breath Phases (Ii2)mentioning

confidence: 99%

Towards standardization in the analysis of breath gas volatiles

Herbig

Beauchamp

2014

J. Breath Res.

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Despite growing interest and considerable progress in breath research over the last decade, standardized practices for the sampling and analysis of breath gas volatiles remain elusive. The primary reasons for this are (a) the rich chemical diversity of exhaled breath that covers an extensive range of volatile organic compounds at highly varied concentrations, (b) the vast disparity in the analytical tools employed, (c) diverse study goals and (d) the presence of (unidentified) confounders. These aspects place stringent but divergent demands on sampling and analysis: each analytical tool, target compound and concentration range requires its own specific protocol and in many cases the latter two are not even known a priori. The ongoing rapid developments and constant discoveries in the field of breath research and the lack of established best practices in breath gas sampling and analysis currently preclude an acceptable overall standardization of these methods. This paper addresses these manifold issues and suggests a framework that separately considers individual stages of sampling and analysis with a view to establishing standardization in the analysis of breath gas volatiles to suit different target compounds and analytical technologies.

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“…Instrumental approaches to isolating alveolar breath have been developed as an enhancement to the use of Haldane-Priestley tube. These have involved hot wire anemometers, 22 Carbon dioxide sensors 17 and timed sampling pumps. 23 The issue of exogenous VOCs and the need for reproducibility Prospecting studies and metabolomic methodologies require data that are obtained under more or less constant experimental conditions, and as such there are many confounding factors that need to be addressed in these areas of research.…”

Section: Voc Extraction and Recovery From Exhaled Breathmentioning

confidence: 99%

An adaptive breath sampler for use with human subjects with an impaired respiratory function

Basanta

Koimtzis

Singh

et al. 2007

Analyst

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An adaptive sampler for collecting 2.5 dm(3) samples of exhaled air from human subjects with an impaired respiratory function is described. Pressure in the upper respiratory tract is continuously monitored and the data used to control an automated system to collect select portions of the expired breathing cycle onto a mixed bed Tenax(trade mark) and Carbotrap(trade mark) adsorbent trap for analysis by GC-MS. The sampling approach is intended for use in metabolomic profiling of volatiles in human breath at concentrations greater than microg m(-3). The importance of experimental reproducibility in metabolomic data is emphasised and consequently a high purity air supply is used to maintain a stable exogenous volatile organic compound profile at concentrations in the range 5 to 30 microg m(-3). The results of a 90 day stability study showed that exogenous VOCs were maintained at significantly lower levels (40 times lower for isopropyl alcohol) and with significantly higher reproducibility (80 times lower standard deviation for isopropyl alcohol) than would have been be the case if ambient air had been used. The sampling system was evaluated with healthy controls alongside subjects with chronic obstructive pulmonary disease. Subjects were able to breathe normally with control subjects observed to breathe at a rate of 9 to 17 breaths per minute, compared to 16 to 30 breaths per minute for subjects with COPD. This study presents, for the first time, observations and estimates of intra-subject breath sample reproducibility from human subjects. These reproducibility studies indicated that VOCs in exhaled breath exhibit a variety of dynamic behaviours, with some species recovered with a RSD <30%, while other species were observed to have significantly more variable concentrations, 30 to 130% RSD. The approach was also demonstrated to reliably differentiate the differences in the VOC profiles between alveolar and dead space air.

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Automatic end-expiratory air sampling device for breath hydrogen test in infants

Cited by 6 publications

References 20 publications

End tidal carbon monoxide concentration in childhood haemolytic disorders

End tidal carbon monoxide concentration in childhood haemolytic disorders

Towards standardization in the analysis of breath gas volatiles

An adaptive breath sampler for use with human subjects with an impaired respiratory function

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