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Sturney S.C.,Respiratory Services | Storer M.K.,Syft Technologies Ltd. | Shaw G.M.,Christchurch Hospital | Shaw D.E.,Nottingham Respiratory Research Unit | Epton M.J.,Respiratory Services
Journal of Breath Research | Year: 2013

Analysis of breath acetone could be useful in the Intensive Care Unit (ICU) setting to monitor evidence of starvation and metabolic stress. The aims of this study were to examine the relationship between acetone concentrations in breath and blood in critical illness, to explore any changes in breath acetone concentration over time and correlate these with clinical features. Consecutive patients, ventilated on controlled modes in a mixed ICU, with stress hyperglycaemia requiring insulin therapy and/or new pulmonary infiltrates on chest radiograph were recruited. Once daily, triplicate end-tidal breath samples were collected and analysed off-line by selected ion flow tube mass spectrometry (SIFT-MS). Thirty-two patients were recruited (20 males), median age 61.5 years (range 26-85 years). The median breath acetone concentration of all samples was 853 ppb (range 162-11 375 ppb) collected over a median of 3 days (range 1-8). There was a trend towards a reduction in breath acetone concentration over time. Relationships were seen between breath acetone and arterial acetone (rs = 0.64, p < 0.0001) and arterial beta-hydroxybutyrate (rs = 0.52, p < 0.0001) concentrations. Changes in breath acetone concentration over time corresponded to changes in arterial acetone concentration. Some patients remained ketotic despite insulin therapy and normal arterial glucose concentrations. This is the first study to look at breath acetone concentration in ICU patients for up to 8 days. Breath acetone concentration may be used as a surrogate for arterial acetone concentration, which may in future have a role in the modulation of insulin and feeding in critical illness. © 2013 IOP Publishing Ltd. Source

Dummer J.,Respiratory Services | Dummer J.,University of Otago | Storer M.,Syft Technologies Ltd. | Swanney M.,Respiratory Services | And 6 more authors.
TrAC - Trends in Analytical Chemistry | Year: 2011

The analysis of volatile biomarkers of disease in breath is attractive because breath analysis is non-invasive and quick, and allows for repeated sampling. Challenges faced in the development of breath analysis include developing techniques that can measure analytes at very low concentrations, gaining an understanding of the exhalation physiology of individual volatiles, and determining the relationship between the proposed biomarker and the underlying condition. A small number of breath tests are used in clinical practice, but there is great potential for the development and wider application of clinical breath analysis in infection, inflammation, cancer and metabolic disease. © 2011 Elsevier Ltd. Source

Dummer J.,Respiratory Services | Storer M.,Syft Technologies Ltd. | Sturney S.,Respiratory Services | Scott-Thomas A.,University of Otago | And 3 more authors.
Journal of Breath Research | Year: 2013

Hydrogen cyanide (HCN) in exhaled breath has been proposed as a biomarker for airway inflammation, and also a marker of the presence in the airways of specific organisms, especially Pseudomonas aeruginosa. However the production of HCN by salivary peroxidase in the oral cavity increases orally exhaled concentrations, and may not reflect the condition of the lower airways. Using SIFT-MS we aimed to determine an appropriate single-exhalation breathing maneuver which avoids the interference of HCN produced in the oral cavity. We have established that the SIFT-MS Voice200™ is suitable for the online measurement of HCN in exhaled breath. In healthy volunteers a significantly higher end exhaled HCN concentration was measured in oral exhalations compared to nasal exhalations (mean ± SD) 4.5 ± 0.6 ppb versus 2.4 ± 0.3 ppb, p < 0.01. For the accurate and reproducible quantification of end exhaled HCN in breath a nasal inhalation to full vital capacity and nasal exhalation at controlled flow is recommended. This technique was subsequently used to measure exhaled HCN in a group of patients with chronic suppurative lung disease (CSLD) and known microbiological colonization status to determine utility of HCN measurement to detect P. aeruginosa. Median nasal end exhaled HCN concentrations were higher in patients with CSLD (3.7 ppb) than normal subjects (2.0 ppb). However no differences between exhaled HCN concentrations of subjects colonized with P. aeruginosa and other organisms were identified, indicating that breath HCN is not a suitable biomarker of P. aeruginosa colonization. © 2013 IOP Publishing Ltd. Source

Storer M.K.,Syft Technologies Ltd. | Dummer J.D.,University of Otago | Cook J.,Respiratory Services | McEwan M.,University of Canterbury | Epton M.J.,Respiratory Services
Journal of Breath Research | Year: 2011

The haloamines, including the chloramines (H2NCl, HNCl 2) and bromamine (H2NBr), are diffusible gases that are likely to be produced during inflammation and so may be present as markers of lung inflammation on breath. Although haloamines are quite reactive, it is possible to measure these compounds in humid samples using SIFT-MS. Until recently the quantification of haloamines in breath suffered from interference from other common breath compounds. This was overcome by heating the flow tube which removed major water cluster product ions. Despite the improvements to the method, previous attempts to measure the haloamines in breath samples from normal volunteers had found no evidence to support their presence. Since it is proposed that the haloamines may be present in higher concentrations during airways inflammation we have attempted to detect the compounds in the exhaled breath of patients with airways inflammatory conditions. On-line and off-line breath samples were analyzed; however, there was no discernable change to any of product ions when compared to ambient air or normal subjects. This suggests that despite sensitivity in the mid part per trillion range haloamines are not significantly raised in airways inflammation. © 2011 IOP Publishing Ltd. Source

Langford V.,Syft Technologies Ltd. | Gray J.,Syft Technologies Ltd. | Foulkes B.,Quintessence Developments Ltd. | Bray P.,Airborne | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2012

Honeys have a range of physicochemical and organoleptic properties, depending on the nectar source. Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) is an emerging technology that quantifies volatile organic compounds (VOCs) to low concentrations (usually parts-per-trillion (ppt) levels) and is here applied to monitor the aromas in the headspace of different New Zealand monofloral honeys. Honey aromas arise from VOCs in the honeys that differ according to the flower type from which they were derived. In this exploratory study, the headspaces of nine monofloral New Zealand honeys (beech honeydew, clover, kamahi, manuka, rata, rewarewa, tawari, thyme, and vipers bugloss) were analyzed using SIFT-MS without sample preparation. The purpose of the investigation was to identify the major volatiles in each of the honeys and to test the feasibility of using SIFT-MS to distinguish between New Zealand monofloral honeys. In the nine monofloral honeys sampled, a clear distinction was observed between them based on their aroma signatures. © 2012 American Chemical Society. Source

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