Video shows the ‘violent’ physical processes in bronchioles that cause wheezing,
A team of Cambridge University bio-engineers have developed a video representation of the oscillations of the bronchioles that for the basis of wheeze.
Applying the complex mathematics of fluid mechanics to airflow within flexible tubes, they produced a model of the bronchioles undergoing the oscillatory motions that produce the characteristic sound of wheezing.
The engineers said that although wheezing has been used to make diagnoses for airways disease for centuries, the physical mechanisms responsible for the onset of wheezing were poorly understood, and there was no model for predicting it.
To mimic the lungs in the lab, the researchers modified a piece of equipment called a Starling resistor, in which airflow is driven through thin elastic tubes of various lengths and thicknesses.
They also developed a multi-camera stereoscopy technique to film air being forced through the tubes at different degrees of tension, in order to observe the physical mechanisms that cause wheezing.
“It surprised us just how violent the mechanism of wheezing is,” said lead author Dr Alastair Gregory.
“We found that there are two conditions for wheezing to occur: the first is that the pressure on the tubes is such that one or more of the bronchioles nearly collapses, and the second is that air is forced though the collapsed airway with enough force to drive oscillations.”
“Our findings allow for a predictive tool for wheezing in lungs, which could lead to better diagnosis and treatment of lung diseases,” they concluded.
Lung Foundation wants action on flavourings
Lung Foundation Australia is calling on politicians to regulate and tax the chemical flavourings used in e-cigarettes, which are especially popular among young people.
CEO Mark Brooke is calling on parliament to take urgent action on the vape liquid flavourings, as most chemicals used in them have not been tested for safety when heated and inhaled.
A recent Australian study found that more than 60% of vape liquids contained chemicals likely to be toxic if vaped repeatedly.
“It is not safe to assume that because a chemical flavouring is used in food or soap, it is safe to inhale,” said Mr Brooke.
“No one’s lungs should be compromised by exposure to unknown and untested aerosols.”
Seven recommendation on nebuliser use to avoid COVID-19 transmission
Asthma Australia has released new cautionary advice to users of nebulisers in the wake of an incident in Melbourne where use of a nebuliser by a man in hotel quarantine was blamed for transmission of COVID-19. The advice explains when it may be appropriate to use a nebuliser – and alternatives such as spacers – and how to minimise the risk of infection transmission if and when they are used. The list of seven things that people with asthma should consider when using a nebuliser at home; includes tips such as making sure other people do not enter the room for at least 30 minutes after use.