The physics of human breathing: flow, timing, volume, and pressure parameters for normal, on-demand,
and ventilator respiration
Normal breathing for healthy humans is taken for granted; it occurs without conscious effort using
ambient (1-atmosphere) pressure with 21% oxygen (O 2 ) concentration. The body automatically adjusts
for stress, exercise, altitude, and mild disease by increasing the volume and frequency of
breathing. Longer term adaptations for exercise and altitude include increases in red blood cell
counts and higher concentrations of capillaries in muscle tissue. When more challenging external
environmental conditions or pulmonary illnesses exceed the capability for these adaptations, the
human system requires technology to mainta...
Source: Journal of Breath Research - September 26, 2021 Category: Respiratory Medicine Authors: Joachim D Pleil, M Ariel Geer Wallace, Michael D Davis and Christopher M Matty Source Type: research
Rationale for developing tunable laser spectroscopy (TLS) technology for high resolution real-time
carbon dioxide monitoring (capnography) in human breath
Real-time monitoring of exhaled carbon dioxide (CO 2 ), also known as capnography, is a valuable
hospital tool for assessing patient health during anesthesia and in both the emergency department
and critical care units. The fundamental measurement is referred to as end-tidal carbon dioxide
concentration that reflects pulmonary gas exchange of CO 2 representing systemic metabolism. The
shape of the exhaled CO 2 concentration for individual inhalation/exhalation breath cycles can offer
additional information regarding lung function, airway obstruction, alveolar ventilation, and
worsening disease. The most frequent use ...
Source: Journal of Breath Research - September 22, 2021 Category: Respiratory Medicine Authors: Joachim D Pleil and Lance E Christensen Source Type: research
Measurements of upper and lower airway nitric oxide in healthy adults
Introduction. Nasal nitric oxide (NO) measurement can be a useful tool for monitoring upper airway
diseases. However, there is a considerable lack of validation data. Aims. To evaluate the
repeatability and intra-subject variations of nasal NO output ( nV NO ) in healthy adults and to
study its correlation with lower airway NO parameters. Methods. nV NO was measured in healthy
non-smokers at baseline ( N = 31, age: 28 ± 6 years), after 1 h ( N = 15), 1 d ( N = 15), 1 week ( N
= 17), and compared using the Bland –Altman method. At baseline, lower airway NO parameters ( F ENO ,
flux of NO in the conducting airways a...
Source: Journal of Breath Research - September 21, 2021 Category: Respiratory Medicine Authors: Bal ázs Csoma, Filippa Beringer, Gergő Szűcs, András Bikov, Veronika Müller and Zsófia Lázár Source Type: research
Efficacy of face masks against respiratory infectious diseases: a systematic review and network
analysis of randomized-controlled trials
During the ongoing COVID-19 pandemic, face masks are among the most common and practical control
measures used globally in reducing the risk of infection and disease transmission. Although several
studies have investigated the efficacy of various face masks and respirators in preventing
infection, the results have been inconsistent. Therefore, we performed a systematic review and
network meta-analysis (NMA) of the randomized-controlled trials (RCTs) to assess the actual efficacy
of face masks in preventing respiratory infections. We searched nine electronic databases up to July
2020 to find potential articles. We acc...
Source: Journal of Breath Research - September 12, 2021 Category: Respiratory Medicine Authors: Thach Quang Tran, Esraa Mahmoud Mostafa, Gehad Mohamed Tawfik, Mohammed Soliman, Seshini Mahabir, Randi Mahabir, Vinh Dong, Rohanti Ravikulan, Suleiman Alhijazeen, Doha Ahmed Farrag, Shyam Prakash Dumre, Nguyen Tien Huy and Kenji Hirayama Source Type: research
Mycotic infection prevalence among patients undergoing bronchoalveolar lavage with search of
SARS-CoV-2 after two negative nasopharyngeal swabs
In this study
we evaluated mycotic isolation prevalence on bronchoalveolar lavage (BAL) of patients who underwent
bronchoscopy in search of severe acute respiratory coronavirus 2 (SARS-CoV-2) RNA. Moreover, we
described the clinical characteristics and main outcomes of these patients. We included 118
patients, 35.9% of them were immunosuppressed for different reasons: in 23.7% we isolated SARS-CoV-2
RNA, in 33.1% we identified at least one mycotic agent and both in 15.4%. On BAL we observed in
three cases Aspergillus spp, in six cases Pneumocystis and in 32 Candida spp. The prevalence of
significant mold infection w...
Source: Journal of Breath Research - September 12, 2021 Category: Respiratory Medicine Authors: Filippo Patrucco, Chiara Airoldi, Zeno Falaschi, Mattia Bellan, Luigi Mario Castello, Francesco Filippone, Simone Matranga, Serena Masellis, Aurora Smeriglia, Paolo Solidoro, Piero Emilio Balbo and Francesco Gavelli Source Type: research
The potential role of SP-D as an early biomarker of severity of asthma
Surfactant decreases the surface tension of peripheral airways and modulates the immunological
responses of the lung. The alterations of surfactant due to the airway inflammation suggest a role
in the pathogenesis of asthma. We aim to test the hypothesis that serum levels of SP-A (Surfactant
Protein A) and SP-D (Surfactant Protein-D) are altered in patients with mild asthma compared to
healthy controls and those alterations are related to functional abnormalities of peripheral
airways, which are an early marker of progression of asthma. In this pilot study, we recruited 20
mild asthmatics and 10 healthy controls. We ...
Source: Journal of Breath Research - September 6, 2021 Category: Respiratory Medicine Authors: Stefania Principe, Alida Benfante, Salvatore Battaglia, Anke H Maitland Van Der Zee and Nicola Scichilone Source Type: research
The peppermint breath test benchmark for PTR-MS and SIFT-MS
A major challenge for breath research is the lack of standardization in sampling and analysis. To
address this, a test that utilizes a standardized intervention and a defined study protocol has been
proposed to explore disparities in breath research across different analytical platforms and to
provide benchmark values for comparison. Specifically, the Peppermint Experiment involves the
targeted analysis in exhaled breath of volatile constituents of peppermint oil after ingestion of
the encapsulated oil. Data from the Peppermint Experiment performed by proton transfer reaction mass
spectrometry (PTR-MS) and selected i...
Source: Journal of Breath Research - September 5, 2021 Category: Respiratory Medicine Authors: Ben Henderson, Gitte Slingers, Michele Pedrotti, Giovanni Pugliese, Michaela Mal ásková, Luke Bryant, Tommaso Lomonaco, Silvia Ghimenti, Sergi Moreno, Rebecca Cordell, Frans J M Harren, Jochen Schubert, Chris A Mayhew, Michael Wilde, Fabio Di Francesco, Source Type: research
Multi-omics study on biomarker and pathway discovery of chronic obstructive pulmonary disease
Chronic obstructive pulmonary disease (COPD) is a common heterogeneous respiratory disease
characterized by persistent and incompletely reversible airflow limitation. Due to the heterogeneity
and phenotype complexity of COPD, traditional diagnostic methods can only provide limited
information on predicted results and treatment, which are not sufficient for accurate diagnosis and
evaluation. With the development of omics technologies in recent years, genomics, proteomics and
metabolomics are widely used in the study of COPD, providing good tools for discovering biomarkers
to diagnose and elucidate the complex mechanis...
Source: Journal of Breath Research - August 31, 2021 Category: Respiratory Medicine Authors: Yuqing Tang, Zhengjun Chen, Zhiling Fang, Jinshun Zhao, Yuping Zhou and Chunlan Tang Source Type: research
Exhaled breath biomarkers of influenza infection and influenza vaccination
Respiratory viral infections are considered a major public health threat, and breath metabolomics
can provide new ways to detect and understand how specific viruses affect the human pulmonary
system. In this pilot study, we characterized the metabolic composition of human breath for an early
diagnosis and differentiation of influenza viral infection, as well as other types of upper
respiratory viral infections. We first studied the non-specific effects of planned seasonal
influenza vaccines on breath metabolites in healthy subjects after receiving the immunization. We
then investigated changes in breath content from ...
Source: Journal of Breath Research - August 19, 2021 Category: Respiratory Medicine Authors: Eva Borras, Mitchell M McCartney, Cai H Thompson, Robert J Meagher, Nicholas J Kenyon, Michael Schivo and Cristina E Davis Source Type: research
Discrimination of COPD and lung cancer from controls through breath analysis using a self-developed
e-nose
This work details the application of a metal oxide semiconductor (MOS) sensor based electronic nose
(e-nose) system in the discrimination of lung cancer and chronic obstructive pulmonary disease
(COPD) from healthy controls. The sensor array integrated with supervised classification algorithms
was able to detect and classify exhaled breath samples from healthy controls, patients with COPD,
and lung cancer by recognizing the amount of volatile organic compounds present in it. This paper
details the e-nose design, participant selection, sampling methods, and data analysis. The clinical
feasibility of the system was che...
Source: Journal of Breath Research - August 2, 2021 Category: Respiratory Medicine Authors: V A Binson, M Subramoniam and Luke Mathew Source Type: research
A perspective on hospital-acquired (nosocomial) infection control of COVID-19: usefulness of spatial
separation between wards and airborne isolation unit
The coronavirus disease 2019 (COVID-19) pandemic has imposed a considerable burden on hospitals and
healthcare workers (HCWs) worldwide, increasing the risk of outbreaks and nosocomial transmission to
‘non-COVID-19’ patients, who represent the highest-risk population in terms of mortality, and HCWs.
Since HCWs are at the interface between hospitals on the one hand and the community on the other,
they are potential reservoirs, carriers, or victims of severe acute respiratory syndrome coronavirus
2 cross-transmission. In addition, there has been a paradigm shift in the management of viral
respiratory outbreaks, suc...
Source: Journal of Breath Research - July 29, 2021 Category: Respiratory Medicine Authors: Kazuyuki Mimura, Hideaki Oka and Makoto Sawano Source Type: research
Medical diagnosis at the point-of-care by portable high-field asymmetric waveform ion mobility
spectrometry: a systematic review and meta-analysis
Non-invasive medical diagnosis by analysing volatile organic compounds (VOCs) at the point-of-care
is becoming feasible owing to recent advances in portable instrumentation. A number of studies have
assessed the performance of a state-of-the-art VOC analyser (micro-chip high-field asymmetric
waveform ion mobility spectrometry, FAIMS) for medical diagnosis. However, a comprehensive
meta-analysis is needed to investigate the overall diagnostic performance of these novel methods
across different medical conditions. An electronic search was performed using the CAplus and MEDLINE
database through the SciFinder platform. T...
Source: Journal of Breath Research - July 27, 2021 Category: Respiratory Medicine Authors: J Diana Zhang, Merryn J Baker, Zhixin Liu, K M Mohibul Kabir, Vijaya B Kolachalama, Deborah H Yates and William A Donald Source Type: research
Oxidative biomarkers of exhaled breath condensate in adults exposed to traffic-related air
pollution: a case-control study
Traffic-related air pollution exposure (TRAP) is a major public health problem. The effects of TRAP
exposure on the oxidative biomarkers of exhaled breath condensate (EBC) of adults are seldom
studied. We compared the oxidative EBC biomarkers in a group of individuals exposed to TRAP with
those of individuals unexposed to TRAP. We conducted a case-control study in Bhopal City (Madhya
Pradesh, India). Adults with a history of exposure to TRAP were enrolled as cases and adults with
less exposure to TRAP were used as a control. Based on respiratory symptoms and smoking habits,
study subjects were stratified into six sub...
Source: Journal of Breath Research - July 21, 2021 Category: Respiratory Medicine Authors: Sajal De, Qmar Khan, Gagan Deep Singh Kushwah, Nalok Banerjee and Pradyumna Kumar Mishra Source Type: research
Pursuing breath research in unprecedented circumstances —report from the Breath Biopsy Conference
2020
The global outbreak of Sars-CoV-2 commencing early in 2020 had a dramatic impact on breath research,
imposing abrupt restrictions but also presenting unforeseen opportunities. Taking place against the
background of the COVID-19 pandemic, the 2020 Breath Biopsy Conference provided the breath research
community with a platform to showcase and discuss the latest findings, including COVID-19 related
research. As with most conferences under the present circumstance, it differed from its predecessor
meetings by shifting to a virtual format, but retained its broad scope and interactive nature. The
conference centred on four...
Source: Journal of Breath Research - June 29, 2021 Category: Respiratory Medicine Authors: Jonathan Lawson and Jonathan Beauchamp Source Type: research
Utility of fractional exhaled nitric oxide in interstitial lung disease
The majority of interstitial lung diseases (ILDs) develop rapidly and are associated with a poor
prognosis. Therefore, new noninvasive markers are needed to guide the classification and
prognostication of ILD. We enrolled 95 patients with ILD, including dermatomyositis-associated ILD (
n = 69), Sj ögren’s syndrome-associated ILD ( n = 7), mixed connective tissue disease-associated ILD
( n = 9), idiopathic pulmonary fibrosis ( n = 5) and hypersensitivity pneumonitis ( n = 5), 82
patients with connective tissue disease but without ILD as well as 24 healthy controls, then
evaluated fractional exhaled nitric oxide (Fe...
Source: Journal of Breath Research - June 14, 2021 Category: Respiratory Medicine Authors: Yu Zheng, Yueyan Lou, Feng Zhu, Xiaodong Wang, Wanlong Wu and Xueling Wu Source Type: research
