Medivent International, The future of respiratory technology

Isn't the RTX Respirator just another negative pressure cuirass device?

NO!

Although it is true that the RTX Respirator uses a cuirass, it would not be accurate to describe the method of ventilation it uses as negative pressure, as the old cuirass ventilators were categorized.

Negative pressure ventilators - While the tank (iron lung) negative pressure ventilators (NPV) provided complete ventilation in some patients with normal lungs (polio, neuromuscular etc.), cuirass NPV per definition could only augment ventilation and could not provide complete ventilation. The reason for this was that whilst the inspiratory phase was active, the passive expiratory phase required time to recoil limiting frequency to most often no more than 30 cycles per minute. As the tidal volume by the cuirass is also limited, minute ventilation (tidal volume x frequency) was low and unable to provide complete ventilation. Furthermore NPV is known to aggrevate heart failure. For these reasons positive pressure replaced it as the preferred method of ventilation.

The RTX's method of ventilation is Biphasic Cuirass Ventilation (BCV) and works by controlling both the inspiratory and expiratory phases of the respiratory cycle. The RTX has frequencies ranging from 6 to 1200 cycles per minute, allowing it to also ventilate at high frequency.

As it is Biphasic it is possible to achieve both higher tidal volumes (the sum of the negative inspiratory tidal volume and positive expiratory tidal volume) as well as higher frequencies. Both of these allow for a much higher minute ventilation to be created thus it is often able to provide complete ventilation with normal and sick lungs. The RTX has managed to overcome many of the drawbacks of negative pressure ventilation. Furthermore, unlike the old negative pressure machines BCV has been shown in clinical studies, to increase cardiac output.

A further advantage in the RTX is its patented cuirass and seal system, which combines flexibility, strength and softness to provide more effective and comfortable ventilation to the patient than other cuirass predecessors which on the whole were much more rigid.

What is the difference between the RTX Respirator and Dr. Hayek's previous respirator, the Hayek Oscillator (H.O)?

More Advanced:
Whilst both the RTX Respirator and the Hayek Oscillator provide biphasic cuirass ventilation (BCV), the RTX is a more technologically advanced and powerful respirator.

More Control, Greater Efficiency & User Friendly:
The RTX is much smaller and lighter, with a TFT graphic display and monitoring capabilities. It has greater control over I:E ratios, can reach frequencies of up to 1200 cpm and reach the required pressures quicker and more efficiently than the Hayek Oscillator (H.O).

Triggered Modes: Greater patient comfort and improved results:
The RTX also has triggered modes; Respiratory triggered mode, respiratory synchronised mode and ECG triggered mode (See RTX Modes of Operation). These allow patients to be ventilated more comfortably in the case of the first two, and to improve cardiac output (even further than in the use of BCV without it) in patients being ventilated using the ECG triggered mode.

More Powerful and Sophisticated:
The RTX works using a blower and valve combination as opposed to the negative baseline method used in the H.O., where a negative pressure pump and bellows were used to generate the pressures and frequencies. This has enabled, along with advancements in computer technology, the RTX to be more powerful and sophisticated.

Superior Cuirass and Seal:
In addition, the RTX cuirass and seal allows for superior comfort for patients and better results through an improved seal, which as well as being more comfortable, is airtight and disposable, and through the RTX cuirass which is better shaped for the patient's comfort and ventilation.

What is the difference between High Frequency Chest Wall Compression (E.g. such as the Vest System) and BCV?

A Great deal!

Whilst both high frequency chest wall compression (HFCWC) systems, such as The Vest system, and Biphasic Cuirass Ventilation (BCV) systems, such as the RTX Respirator, provide secretion clearance treatment and can work at high frequencies, they are two totally different methods, which must be distinguished between.

Secretion Clearance
High frequency chest wall compression has only one active phase (on the chest) and compresses the chest from its initial lung volume (FRC) to below lung volume as it compresses, and then recoils back towards its initial lung volume. It has been shown in animal studies that this may cause reduction in FRC (Zidulka - High Frequency Chest Wall Compression Am Rev of Respir Dis 1983; 127: 709-713). This may not be favourable with patients that have some alveolar collapse, which many of the patients requiring secretion clearance treatment have.

The biphasic cuirass method has two active phases. One increases lung volume to above FRC (initial lung volume) by expanding the chest and only then compressing the chest to the desired level, preserving or augmenting lung volume (and thus avoiding lung collapse), and creating substantial expiratory airflow during secretion clearance and ventilation. This allows for the creation of a very efficient and physiological secretion clearance method.

To consider or describe BCV devices such as the Hayek Oscillator or the RTX Respirator as high frequency chest wall compression devices is absolutely incorrect, both in terms of the method used and in terms of the results achieved.

Isn't the RTX Respirator just another negative pressure cuirass device?
NO! Although it is true that the RTX Respirator uses a cuirass, it would not be accurate to describe the method of ventilation it uses as negative pressure, as the old cuirass ventilators were categorized. Negative pressure ventilators - While the tank (iron lung) negative pressure ventilators (NPV) provided complete ventilation in some patients with normal lungs (polio, neuromuscular etc.), cuirass NPV per definition could only augment ventilation and could not provide complete ventilation. The reason for this was that whilst the inspiratory phase was active, the passive expiratory phase required time to recoil limiting frequency to most often no more than 30 cycles per minute. As the tidal volume by the cuirass is also limited, minute ventilation (tidal volume x frequency) was low and unable to provide complete ventilation. Furthermore NPV is known to aggrevate heart failure. For these reasons positive pressure replaced it as the preferred method of ventilation. The RTX's method of ventilation is Biphasic Cuirass Ventilation (BCV) and works by controlling both the inspiratory and expiratory phases of the respiratory cycle. The RTX has frequencies ranging from 6 to 1200 cycles per minute, allowing it to also ventilate at high frequency.
As it is Biphasic it is possible to achieve both higher tidal volumes (the sum of the negative inspiratory tidal volume and positive expiratory tidal volume) as well as higher frequencies. Both of these allow for a much higher minute ventilation to be created thus it is often able to provide complete ventilation with normal and sick lungs. The RTX has managed to overcome many of the drawbacks of negative pressure ventilation. Furthermore, unlike the old negative pressure machines BCV has been shown in clinical studies, to increase cardiac output. A further advantage in the RTX is its patented cuirass and seal system, which combines flexibility, strength and softness to provide more effective and comfortable ventilation to the patient than other cuirass predecessors which on the whole were much more rigid.
What is the difference between the RTX Respirator and Dr. Hayek's previous respirator, the Hayek Oscillator (H.O)?
	More Advanced: Whilst both the RTX Respirator and the Hayek Oscillator provide biphasic cuirass ventilation (BCV), the RTX is a more technologically advanced and powerful respirator. More Control, Greater Efficiency & User Friendly: The RTX is much smaller and lighter, with a TFT graphic display and monitoring capabilities. It has greater control over I:E ratios, can reach frequencies of up to 1200 cpm and reach the required pressures quicker and more efficiently than the Hayek Oscillator (H.O). Triggered Modes: Greater patient comfort and improved results: The RTX also has triggered modes; Respiratory triggered mode, respiratory synchronised mode and ECG triggered mode (See RTX Modes of Operation). These allow patients to be ventilated more comfortably in the case of the first two, and to improve cardiac output (even further than in the use of BCV without it) in patients being ventilated using the ECG triggered mode. More Powerful and Sophisticated: The RTX works using a blower and valve combination as opposed to the negative baseline method used in the H.O., where a negative pressure pump and bellows were used to generate the pressures and frequencies. This has enabled, along with advancements in computer technology, the RTX to be more powerful and sophisticated. Superior Cuirass and Seal: In addition, the RTX cuirass and seal allows for superior comfort for patients and better results through an improved seal, which as well as being more comfortable, is airtight and disposable, and through the RTX cuirass which is better shaped for the patient's comfort and ventilation.
What is the difference between High Frequency Chest Wall Compression (E.g. such as the Vest System) and BCV?
A Great deal! Whilst both high frequency chest wall compression (HFCWC) systems, such as The Vest system, and Biphasic Cuirass Ventilation (BCV) systems, such as the RTX Respirator, provide secretion clearance treatment and can work at high frequencies, they are two totally different methods, which must be distinguished between. Secretion Clearance High frequency chest wall compression has only one active phase (on the chest) and compresses the chest from its initial lung volume (FRC) to below lung volume as it compresses, and then recoils back towards its initial lung volume. It has been shown in animal studies that this may cause reduction in FRC (Zidulka - High Frequency Chest Wall Compression Am Rev of Respir Dis 1983; 127: 709-713). This may not be favourable with patients that have some alveolar collapse, which many of the patients requiring secretion clearance treatment have. The biphasic cuirass method has two active phases. One increases lung volume to above FRC (initial lung volume) by expanding the chest and only then compressing the chest to the desired level, preserving or augmenting lung volume (and thus avoiding lung collapse), and creating substantial expiratory airflow during secretion clearance and ventilation. This allows for the creation of a very efficient and physiological secretion clearance method. To consider or describe BCV devices such as the Hayek Oscillator or the RTX Respirator as high frequency chest wall compression devices is absolutely incorrect, both in terms of the method used and in terms of the results achieved.

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