This is an exciting use of old technology

Dame Helena Shovelton, BLF

The "vacuum study" was carried out to enable doctors to look at the endurance of breathing muscles, rather than their just their strength.

The test provides information on how the breathing muscles cope under a stressful load over a long period.

Symptoms

It is assumed that most lung disease symptoms are caused by damage to the lung tissue itself.

However, lung disease can also put an excessive load on the breathing muscles.

These muscles, of which the diaphragm is the best known, are responsible for movement of air into the chest cavity and breathing muscle dysfunction can result in breathlessness and even respiratory failure.

Although the strength of the breathing muscles can be readily measured, it may actually be more useful to measure their endurance.

This provides information on how the breathing muscles will cope under a stressful load over a prolonged period.

However, until now, tests of breathing muscle endurance have not made it into clinical practice due to difficulties in gaining data which can be reproduced.

Innovative solution

Doctors at the Royal Brompton, headed by Dr Michael Polkey, have used a vacuum cleaner to overcome this problem.

Basically, they measure the stress on the breathing muscles while the patient tries to breathe out against the negative pressure created by the vacuum cleaner.

The only drawback to the vacuum tests was that a small pressure-monitoring catheter had to be inserted into the food pipe to measure the pressure in the chest.

However, it was shown that pressure measured at the mouth reflected the pressure in the chest.

The doctors believe that future studies could be performed without this catheter in certain patients.

Dame Helena Shovelton, chief executive of the British Lung Foundation, said the experiments were "an innovative use of old technology".

She said: "Developing uses in technology is very important for better diagnosing and treatment of lung disease.

"Using a vacuum cleaner to test negative pressure is one example."

She said the more research using technology there was the better to help those living with a lung disease.

The research is published in the European Respiratory Journal (ERJ).