This research theme conducts research on the development, improvement and optimization of respiratory therapy methods and devices. Research is focused on therapy and relief within the conductive and terminal respiratory system and includes the peripheral sinuses, mouth and nasal cavity. Main areas of research include therapy devices for obstructive sleep apnea, respiratory distress syndrome, asthma and the treatment of sinus disorders. Internal research includes the investigation of a non-medicinal technique to relieve contracted airway passages such as those experienced during an asthma attack.
Research activities under this theme are focused on two areas, respiratory system dynamics and respiratory devices.
A. Respiratory System Dynamics
Respiratory disorders are common in both developed and developing countries. Many of these disorders are directly connected to the constrictions in the airways of the human respiratory system. Asthma and bronchitis are typical examples that arise from the constriction of airways. Asthma is a respiratory disease that is characterised by chronic inflammation, hypersensitivity, and obstruction of the airways. During an asthma attack contraction of airway smooth muscle and mucous production cause a reduction of the bronchial diameter, significantly changing the airflow resistance in and out of the lungs.
The main aim of this research is to identify non-conventional techniques of relieving constrictions in the airway passages, such as those caused by asthma to minimize or replace the use of medication.
- Relaxation of Airway Smooth Muscle by Length Oscillation
It has been proven that airway smooth muscle can be relaxed using length oscillation. The aim of this research is to identify which processes in airway smooth muscle are responsible for the relaxation, and to determine the amount of force reduction caused by length oscillation.
This involves developing a quantitative and integrated mathematical model of the smooth muscle tissue using finite element modelling with purpose built material models to describe force reduction due to vibrations. This definitive model can help identify actual processes responsible for force generation and relaxation in the airway smooth muscle cell.
- Combined Oscillation and Drug Relaxation of Airway Smooth Muscle
The aim of this project is to study the combined effects of vibration and medications on the contracted airway smooth muscle, thereby reducing the use of medications.
- Dynamic Investigation of Airways
The respiratory system consists of a series of branching tubes which become narrower, shorter and more numerous as they penetrate deeper into the lung. From a mechanics point of view, the walls of these passages are composed of viscoelastic material. A system that possesses mass and elastic properties exhibits natural frequencies at different modes of vibration, which are inherent to the system.
This research focuses on the area of the acoustic and vibration response of the lung. It is expected to develop a robust theoretical model, supported by experimental validation that predicts the dynamic characteristics of airways in terms of the natural frequencies of the branched tree structure.
- Upper Airway Dynamics
Obstructive sleep apnea (OSA) is considered one of the threatening diseases to the quality of life. It is considered the most worldwide common upper respiratory airway syndrome, and is one of the main sleep-disorder breathing diseases. OSA occurs due to obstruction in the upper airway (UA) region and characterized by repeated obstruction and collapse of the pharyngeal airway during sleep. OSA can result in many health implications such as hypertension, stroke, cardiovascular disease and low sexual drive in men.
UA collapse occurs when the forces of the airway muscles are less than those generated from the airway negative pressures during respiration. The tendency for the upper airway obstruction is increased when the patient sleeps in supine position, at which the gravitational forces may push the soft palate tip (uvula) and tongue towards the airway wall, which in turn reduces the gap between those tissues and airway wall, thus increases the chance for airway obstruction and collapse. Our research focuses on looking at various ways of physically stimulating the UA and determining the best conditions for improvement. This includes, but not limited to:
- Determining the vibration characteristic of the UA.
- Understanding the humidification process of the UA.
- Treatment of Chronic Rhinosinusitis
We have recently started working on the use of ultrasound, vibration and electrical field therapy for the treatment of chronic rhinosinusitis.
B. Respiratory Devices
This area focuses on modelling, optimisation and development of respiratory therapy devices. Over the last 17 years, IBTec has carried out more than 30 successful projects with Fisher and Paykel Healthcare on the development and improvement of CPAP systems. Some of the major projects currently include:
- Development of New Generation CPAP Devices
This project is completed.
- The Effect of Pressure Oscillations on Neonatal Breathing
This project aims to create a mathematical model of the neonatal respiratory system which is able to predict the mechanical response to pressure oscillations produced by the Bubble CPAP system. The model considers both the viscoelastic and surface tension effects within the respiratory system. These models are to be validated by trials on live subjects in both experimental and clinical settings.
- The effect of CPAP pressure on UA humidification
This project aims to understand the relationship between the CPAP titration pressure and the humidification of the UA.
- Acoustic and Vibration Characteristics of CPAP
This project focuses on investigating the acoustic and vibration characteristics of CPAP machine in order to identify critical design parameters for quieter CPAP.
- Understanding Upper Airway Humidification
This research is sponsored by F&P Healthcare to understand the correlation between CPAP applications and upper airway humidification.
- Development of Miniaturised Humidifier
Humidifiers are essential in many lung supportive devices including but is not limited to intensive care units, CPAP devices and others. This project looks at a new technology to get rid of old type convective types of humidifiers and replace it with compact miniaturised type humidifiers.