An Investigation Into the Effects of Pressure Oscillations on Airway Smooth Muscle in Chronic Asthma

aut.embargoNoen_NZ
aut.thirdpc.containsNoen_NZ
dc.contributor.advisorAl-Jumaily, Ahmed
dc.contributor.advisorLu, Jun
dc.contributor.advisorCairns, Simeon
dc.contributor.authorRoos, Kevin Lamar Turepu
dc.date.accessioned2018-11-14T01:42:03Z
dc.date.available2018-11-14T01:42:03Z
dc.date.copyright2018
dc.date.issued2018
dc.date.updated2018-11-12T23:40:35Z
dc.description.abstractThe hyperconstriction of airway smooth muscle (ASM) is the main driving mechanism during an asthmatic attack. The airway lumen is reduced, resistance to airflow increases, and normal breathing becomes more difficult. The tissue contraction can be temporarily relieved by using bronchodilator drugs which induce relaxation of the constricted airways. With one of the highest prevalence rates in the world, New Zealand’s costs for asthma treatments total an estimated NZD$825 million per year. While widely used in asthma therapies, pharmacological treatments vary in their effectiveness from one subject to another, as do the side effects of long-term usage. Studies have shown that application of mechanical oscillations which are equivalent to the physiological patterns of normal breathing and deep inspirations in healthy airways can induce airway relaxation. This type of relaxation response is not observed in asthmatics. Utilizing length oscillations (arising from positive pressure) in association with breathing patterns provides non-pharmacological options for augmenting treatment of the ASM hyperconstriction which is present in many respiratory diseases such as asthma. There is currently little known about the effects of applying superimposed pressure oscillations in combination with breathing patterns to healthy and asthmatic airways during an asthmatic attack. Results from in vivo studies of a chronic murine asthmatic model indicate that the use of superimposed pressure oscillations (SIPO) over normal breathing patterns facilitates relaxation during an induced asthmatic attack in healthy and asthmatic subjects. Oscillation patterns, physiological pressure equivalents, and their effects on key respiratory parameters are presented. Comparisons of healthy and asthmatic lung resistance (RL) and dynamic compliance (Cdyn) values are used as assessments of the changes in airway responses to applied mechanical pressure oscillations. Additionally, a standard respiratory constant is used to normalize acute and chronic asthmatic models’ data. Use of the constant assists in modeling the effects of SIPO by transforming RL and Cdyn data into Work and Power equivalents for use in interpreting ASM mechanics.en_NZ
dc.identifier.urihttps://hdl.handle.net/10292/11997
dc.language.isoenen_NZ
dc.publisherAuckland University of Technology
dc.rights.accessrightsOpenAccess
dc.subjectMechanical oscillationsen_NZ
dc.subjectSuperimposed pressure oscillationsen_NZ
dc.subjectAirway smooth muscleen_NZ
dc.subjectBreathingen_NZ
dc.subjectContractionen_NZ
dc.subjectRelaxationen_NZ
dc.subjectResistanceen_NZ
dc.subjectComplianceen_NZ
dc.titleAn Investigation Into the Effects of Pressure Oscillations on Airway Smooth Muscle in Chronic Asthmaen_NZ
dc.typeThesisen_NZ
thesis.degree.grantorAuckland University of Technology
thesis.degree.levelDoctoral Theses
thesis.degree.nameDoctor of Philosophyen_NZ
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
RoosKLT.pdf
Size:
3.47 MB
Format:
Adobe Portable Document Format
Description:
Thesis
License bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
license.txt
Size:
889 B
Format:
Item-specific license agreed upon to submission
Description:
Collections