Ludwig Engel Centre for Respiratory Research
Associate Professor John Wheatley is the Director of the Ludwig Engel Centre for Respiratory Research.
Our Respiratory Research is focussing on:
Obstructive Sleep Apnoea Syndrome
The main focus of our research program in sleep disordered breathing and upper airway physiology is the development of an understanding of the mechanisms underlying the obstructive sleep apnoea syndrome (OSA).
In this disorder, which occurs in about 5% of men and 2% of women over the age of 45 years, patients experience repetitive episodes of throat blockage during sleep. This leads to breathing difficulties including complete cessation of breathing for short periods of time.
Sleep disordered breathing leads to sleep disruption and episodes of poor oxygenation of the blood - it can happen hundreds of times each night in severe cases. This causes major disruption to daytime function including fatigue, poor concentration and mental abilities, excessive daytime sleepiness, and an increase in the occurrence of accidents (eg falling asleep at the wheel of a motor vehicle).
As the condition continues over the years other medical problems develop and links have been established between OSA and the occurrence of heart disease, high blood pressure and stroke.
Our researchers are working to understand the processes associated with the occurrence of obstructed breathing during sleep in order to improve the treatment of this important disorder.
Studies during sleep in patients with obstructive sleep apnoea demonstrated, for the first time, that lowering the surface tension of the liquid lining the upper airway leads to a reduction in the severity of sleep disordered breathing. This work opens a new therapeutic approach to the treatment of obstructive sleep apnoea.
Cystic fibrosis
Cystic fibrosis is the most common lethal inherited disease affecting Australians.
In CF, altered salt transport across the lining of the airways leads to drying of the airway surface which impedes the processes which remove mucus from the lungs. Mucus retention makes the lungs very susceptible to bacterial infections. People with CF experience repeated chest infections requiring constant medical care.
Our researchers are working to understand the processes by which mucus retention occurs in CF patients and to develop new treatments which will improve airway function in these patients leading to a longer life expectancy and improved quality of life for CF patients.
We have recently demonstrated that the human airway responds to a decrease in calcium concentration in the airway surface liquid (ASL) by an increase in potential difference (PD). This response was rapid, reversible and observed in both CF and non-CF subjects, suggesting that extracellular calcium modulates ion transport in both CF and non CF airway epithelia, possibly via a similar ion transport mechanism.
We are currently investigating the use of calcium chelators, which bind calcium, to further lower extracellular calcium. These chelators may improve mucous movement and lung function and consequently may prove to be a new effective treatment for CF lung disease.
Asthma
Asthma now affects the lives of over two million Australian children and adults. Despite decades of research into the causes and treatment of asthma the prevalence of asthma in the population continues to rise.
A major research interest in the Ludwig Engel Centre is the influence of mouth versus nose breathing on the occurrence of asthmatic symptoms in asthma patients. The nose warms, humidifies and filters inspired air, whereas mouth breathing exposes the lungs to unheated, dry, unfiltered air which may contribute to the occurrence or worsening of an asthmatic attack.
Early work has shown that mouth breathing is common during an asthmatic attack and that asthmatic patients will switch easily from nose to mouth breathing. Currently, researchers are investigating whether nose breathing can help to resolve an episode of airway narrowing.
Our research recognised that asthmatic subjects have altered perception of nasal obstruction, leading them to switch to mouth breathing more readily than healthy individuals and that mouth breathing in asthmatics may lead to the development of an asthma episode.
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