Cystic fibrosis (CF) is characterised by the accumulation of thick, tenacious and infected secretions in the lungs.

Removing these secretions remains one of the cornerstones in caring for patients with cystic fibrosis. Physiotherapy is a way of clearing the thick, sticky mucus from the lung

Parents are taught how to do this for their children. Adults with CF can learn how to administer their own physiotherapy. (see the physiotherapy techniques section below)

As well as the physiotherapy to mobilise the secretions within the lungs the forced expiration technique or huff: is used to mobilise and clear secretions up the airways so you can cough them out

The Secretion Clearance mode on this works in a very unique and different way to all other secretion clearance devices on the market. Whilst being underpinned by the high frequency chest wall oscillation (HFCWO) technology, develop by Dr Z Hayek in 1984, it is the only true HFCWO machine on the market. This is because to achieve effective oscillation of the chest the device must have to ability to move between a negative pressure, which expands the lungs by sucking the chest wall out, and a positive pressure, which compresses the lungs.

This negative to positive pressure change means that as the lungs are inflated by the Medivent Hayek RTX the secretions are mobilised more effectively and efficiently. Whilst the cuirass/shell only goes over your chest secretions in all the areas of your lungs are effectively mobilised.

The other unique feature of the Medivent Hayek RTX, in relation to secretion clearance, is that, it incorporates a cough simulation element to the function. This replaces the ‘Huff’ techniques that you may perform to expel the mobilised secretion up the respiratory tract.

The second element is the cough simulator. This works by giving a long high pressure breathe in followed by a short sharp breath out forcing the secretions up the airways. This enables you to expel them more easily.

"it is remarkable that the patient expelled sputum whenever he was connected...far beyond that achievable by physiotherapy" Respiration and Circulation

The Medivent Hayek RTX not only provides the secretion clearance function for you, it also provides non-invasive ventilation should you require it. The method of ventilation it employs is proven to build up your respiratory muscle strength as it uses them to help you breathe (see the section on Biphasic cuirass ventilation (BCV) below for how this works).

Patients with CF are required to perform these airway clearance techniques both during acute respiratory exacerbations and periods of clinical stability (Orenstein D 2002) Despite the essential nature of airway clearance techniques, they are often an onerous task for patients with CF and have been associated with increased energy expenditure, oxygen desaturation, respiratory muscle fatigue, and dyspnoea.(Williams et al 2201, Miller et al 1995, Fauroux et al 1999, Cecins et al 1999) These effects are likely to be greatest during an acute exacerbation when energy expenditure is increased due to infection and inflammation, and bronchial obstruction and respiratory muscle performance are at their worst (Noah et al1993). These factors may compromise the patient’s ability to perform airway clearance techniques at a time when it is most crucial.

The Active Cycle of Breathing Techniques: (Pryor et al, 1979; Webber et al, 1986; Webber, 1990). This consists of a combination of deep breathing exercises (DBE); thoracic expansion exercises (TEE); forced expiratory technique (FET) and breathing control. The Active Cycle of Breathing Techniques (ACBT) is not a rigid treatment method and is modified to suit all ages and individual need.

Percussion, chest clapping and postural drainage are all important parts on manual chest physiotherapy that CF patients are required to undergo.

The Medivent RTX works using a unique Biphasic Cuirass Ventilation (BCV) technique. A negative pressure is generated within the chest cuirass, for inspiration or continuous inspiratory assistance, and applies a positive pressure within the cuirass inducing expiration. This positive expiratory pressure means that expiration is an active phase in the respiratory cycle this makes the RTX particularly efficient at CO2 clearance (Dolmage et al 1995, Segawa et al 1993)

Ventilation using the Medivent Hayek RTX is the closest method of ventilation we have to physiological respiration. It works by generating a negative pressure inside the cuirass/shell and sucking the diaphragm down and the intercostal muscles out. This in turn causes the pressure in the lungs to decrease and become lower than the surrounding atmosphere. This lower pressure causes the air outside to rush into the chest and expand the lungs. This is how we breathe normally. http://www.csmc.edu/6932.html

This in turn means that with this mode of ventilation your own respiratory muscles are being used to help your breathing and are in turn being strengthened.

‘We conclude that INPV may be effective in improving the functional reserve of the inspiratory muscles’ N Ambrosino et al

As ventilation is Biphasic, it is possible to achieve both higher tidal volumes (negative inspiratory tidal volume and positive expiratory tidal volume), higher frequencies -from 6 to 1200CPM, and also for the user to have proper and real control over I:E Ratio, without having to depend on passive recoil of the patient.

In addition, the patented technology used for the cuirass and its disposable seal in the RTX allows for a comfortable fit and seal of the air within the cuirass. These advantages allow for a much higher minute ventilation to be created and thus making complete ventilation possible in both normal and sick lungs.