Background: This study quantifies the time-varying flow rate during inspiration at rest and in sniffing, both predecongestion and postdecongestion. It aims to provide a better understanding of nasal airflow mechanics, for application to the physiological modeling of nasal respiration and to therapeutic drug delivery.
Methods: The temporal profiles of nasal inspiration were measured at high fidelity in 14 healthy individuals using simultaneous bilateral hot-wire anemometry. Peak nasal inspiratory flow (PNIF) rate, acoustic rhinometry (AR), and the sinonasal outcome test (SNOT) provided complementary clinical measurements. The impact of decongestion was also investigated.
Results: In the initial phase of inspiration, a rapid rise in flow rate was observed. Flow first exceeded 150 mL/second in either passage within a median time of approximately 120 ms for inspiration at rest and approximately 60 ms in sniffing (∼20 ms in the fastest sniffs). The mean sustained flow rate attained and the overall period of each measured inspiratory profile were analyzed. AR showed a significant change in nasal volume with decongestion, although these change were not manifest in the temporal profiles of inspiratory flow (barring a weak effect associated with the most vigorous sniffs).
Conclusion: Novel methods were applied to investigate the temporal profiles of nasal inspiration. Characteristic features of the profile were identified and found to be significantly different between inspiration at rest and sniffing. Decongestion was found to have little effect on the temporal profiles for the flow regimes studied.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/alr.20021 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Efficacy of Combined Visual-Olfactory Training With Patient-Preferred Scents as Treatment for Patients With COVID-19 Resultant Olfactory Loss: A Randomized Clinical Trial.
JAMA Otolaryngol Head Neck Surg
February 2023
Clinical Outcomes Research Office, Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine in St Louis, St Louis, Missouri.
Importance: The number of olfactory dysfunction cases has increased dramatically because of the COVID-19 pandemic. Identifying therapies that aid and accelerate recovery is essential.
Objective: To determine the efficacy of bimodal visual-olfactory training and patient-preferred scents vs unimodal olfactory training and physician-assigned scents in COVID-19 olfactory loss.
Delta-range coupling between prefrontal cortex and hippocampus supported by respiratory rhythmic input from the olfactory bulb in freely behaving rats.
bioRxiv
February 2021
Dept Psychiatry at BIDMC, Harvard Medical School.
An explosion of recent findings firmly demonstrated that brain activity and cognitive function in rodents and humans are modulated synchronously with nasal respiration. Rhythmic respiratory (RR) coupling of wide-spread forebrain activity was confirmed using advanced techniques, including current source density analysis, single unit firing, and phase modulation of local gamma activity, creating solid premise for investigating how higher networks use this mechanism in their communication. Here we show essential differences in the way prefrontal cortex (PFC) and hippocampus (HC) process the RR signal from the olfactory bulb (OB) allowing dynamic PFC-HC coupling utilizing this input.
View Article and Find Full Text PDF[The active butanol detection threshold remains the same during exercise].
Laryngorhinootologie
July 2020
Klinik für Hals-, Nasen- und Ohrenkrankheiten, Uniklinikum, Jena, Germany.
Background: The active butanol detection thresholds (B-DT), determined using the sniffin' sticks, show a high intra- and inter-individual test-retest reliability, although the internal stimulus concentration may vary considerably depending on the dilution of the external stimulus concentration with odorless ambient air during active sniffing. There are various hypotheses for this surprising result. In this study, it should be tested whether a larger respiratory effort (vigor) under physical stress changes the active B-DT.
View Article and Find Full Text PDFRole of deep breaths in ultrasonic vocal production of Sprague-Dawley rats.
J Neurophysiol
March 2020
Department of Physiology, College of Graduate Studies, Midwestern University, Glendale, Arizona.
Deep breaths are one of three breathing patterns in rodents characterized by an increased tidal volume. While humans incorporate deep breaths into vocal behavior, it was unknown whether nonhuman mammals use deep breaths for vocal production. We have utilized subglottal pressure recordings in awake, spontaneously behaving male Sprague-Dawley rats in five contexts: sleep, rest, noxious stimulation, exposure to a female in estrus, and exposure to an unknown male.
View Article and Find Full Text PDFLocal cortical activity of distant brain areas can phase-lock to the olfactory bulb's respiratory rhythm in the freely behaving rat.
J Neurophysiol
September 2018
Department of Neuroscience and Biomedical Neuroscience Institute, Universidad de Chile , Santiago , Chile.
An important unresolved question about neural processing is the mechanism by which distant brain areas coordinate their activities and relate their local processing to global neural events. A potential candidate for the local-global integration are slow rhythms such as respiration. In this study, we asked if there are modulations of local cortical processing that are phase-locked to (peripheral) sensory-motor exploratory rhythms.
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!