Measurement of exhaled nitric oxide (eNO) offers a non-invasive means for assessment of airway inflammation. The currently available methods are difficult to apply in preschool children. We evaluated four methods potentially applicable for eNO measurement during tidal breathing in young children. eNO was assessed during tidal breathing in 24 children, 2-7 yr old, using a facemask which separated nasal and oral airflow. Facemasks with and without a one-way valve allowing exhalation through the nose were used. Expiratory flow control was not attempted. Measurements of eNO were performed both on-line and off-line. In 11 children, 8-12 yr old, measurements were compared with the standard single breath on-line method. eNO was significantly lower applying the one-way valve in on-line and off-line measurements in comparison with measurements without the valve [4.6 and 3.9 parts per billion (ppb) vs. 6.9 ppb and 6.5 ppb]. The mean within subject coefficient of variation (CV) was significantly lower in on-line measurements with the one-way valve (9.6%) compared with the other three methods (18.8, 27.7 and 29.3% respectively). Measurements with a facemask fitted with a one-way valve yielded similar eNO levels as the standard single breath method (7.0 ppb vs. 6.9 ppb) and reproducibility (9.8% vs. 7.1%). In conclusion, reproducible measurements of eNO can be obtained without control of expiration flow using a facemask fitted with a one-way valve on the nasal compartment. The likely explanation to this is that the one-way valve reduces the admixture of nasal NO, thereby improving the reliability of eNO measurements.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1399-3038.2005.00209.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Recapitulation of physiologic and pathophysiologic pulsatile CSF flow in purpose-built high-throughput hydrocephalus bioreactors.
Fluids Barriers CNS
December 2024
Department of Chemical Engineering and Materials Science, Wayne State University, 6135 Woodward Avenue, Rm 1413, Detroit, MI, 48202, USA.
Background: Hydrocephalus, an accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain, is often treated via a shunt system to divert the excess CSF to a different compartment; if left untreated, it can lead to serious complications and permanent brain damage. It is estimated that one in every 500 people are born with hydrocephalus. Despite more than 60 years of concerted efforts, shunts still have the highest failure rate of any neurological device requiring follow-up shunt revision surgeries and contributing to the $2 billion cost of hydrocephalus care in the US alone.
View Article and Find Full Text PDFFabrication and in vivo testing of a sub-mm duckbill valve for hydrocephalus treatment.
Microsyst Nanoeng
December 2024
Department of Electrical, Computer and Energy Engineering, Arizona State University, 650 E. Tyler Mall, Tempe, AZ, USA.
Hydrocephalus is characterized by the accumulation of excess cerebrospinal fluid (CSF) in the cranium due to an imbalance between production and absorption of CSF. The standard treatment involves the implantation of a shunt to divert excess CSF into the peritoneal cavity, but these shunts exhibit high failure rates over time. In pursuit of improved reliability and performance, this study proposes a miniaturized valve designed to mimic the natural one-way valve function of the arachnoid granulations and thereby replace the shunts.
View Article and Find Full Text PDFTricuspid Valve S-Curves and Chamber Views: Implications for Transcatheter Tricuspid and Pulmonary Valve Interventions, Part 2 of the S-Curves and Chamber Views Series.
JACC Cardiovasc Interv
December 2024
Division of Cardiology, Department of Medicine, Glen Hospital, McGill University Health Center, Montreal, Quebec, Canada. Electronic address:
Despite the challenges associated with periprocedural imaging, transcatheter tricuspid valve interventions have shown important impact on outcomes. A comprehensive understanding of the anatomy of the right heart and surrounding structures is crucial. One way to optimize these interventions is by identifying the optimal fluoroscopic viewing angles along the S-curve of the tricuspid valve.
View Article and Find Full Text PDFPrevention of Air Embolism in Extracorporeal Membrane Oxygenation Systems: An In Vitro Study on Protection of Central Venous Catheter Lumen.
Medicina (Kaunas)
November 2024
Center for Intensive Internal Medicine, University Medical Center, Zaloska 7, 1000 Ljubljana, Slovenia.
Article Synopsis
- * It found that using interventions like a closed three-way stopcock or clave significantly prevented air entry, while small volumes of air (1 mL) could still cause dysfunction at certain pump speeds.
- * Auditory cues, such as a hissing sound, were identified as important early warnings for detecting air presence in the circuit, contributing to the overall safety of ECMO systems and reducing the risk of air embolism.
Comparison of Efficacy and Safety of Different Types of One-Way Valves in Endoscopic Lung Volume Reduction in Patients with Severe Lung Emphysema.
Respiration
November 2024
Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Introduction: Endoscopic lung volume reduction (ELVR) with valves is an effective intervention in patients with severe lung emphysema. Two types of valves are established in clinical practice: Zephyr endobronchial valves (EBVs) and Spiration Valve System (SVS). We aimed to compare outcomes and the safety associated with these two types of one-way valves.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!