Surgery – Respiratory method or device – Means for mixing treating agent with respiratory gas
Patent
1998-04-27
2000-08-08
Lewis, Aaron J.
Surgery
Respiratory method or device
Means for mixing treating agent with respiratory gas
12820314, A61M 1500
Patent
active
060986182
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND
The present invention relates to an inhalation device for providing a substance in a dispersed state.
Inhalable pharmaceutically active substances are generally used for the treatment of diseases in the bronchial and pulmonary areas, such as asthma and chronic bronchitis. Various kinds of inhalation devices are used for this purpose.
One kind of inhalation device is the breath-actuated inhaler, particularly but not necessarily a dry powder inhaler, which contains multiple doses of powder containing an active substance. One such inhaler is the Turbuhaler.RTM. dry powder inhaler. Such an inhaler has a rotatable grip portion for providing a dose of powder for inhalation. Inhalers of this kind are disclosed in EP-A-0069715 and EP-A-0237507.
SUMMARY OF THE INVENTION
The operation of this inhaler relies on the creation of an air flow resulting from inhalation by a user. The air flow draws up the powder containing active substance and disperses the same therewithin. Deagglomeration of agglomerates must also be achieved during inhalation; agglomerates always occurring in fine powders, especially finely divided powders of the kind suitable for inhalation.
Some patients such as small children and the elderly with bronchial diseases are, however, not able to use breath-actuated inhalers as these patients cannot develop the necessary inhalation flow rates, typically about 30-60 l/min. These patients have to use pressurised metered dose inhalers which use a propellant such as freon (CFC). Such inhalers suffer from many known disadvantages, particularly undesirable side effects both for the environment and the patients.
In order to facilitate the inhalation of pharmaceutically active substances which are delivered by the use of pressurised metered dose inhalers, it is known to use dispersion chambers of considerable volume, typically up to 2000 ml, into which the substance entrained in the pressurised gas is dispersed. These devices are generally known as spacers. GB-A-1565029 discloses a typical spacer.
Inhalation devices which include dispersion chambers have also been developed for dry-powder inhalers of the above-mentioned kind. One such an inhalation device is disclosed in EP-A-0548152. This device comprises a reservoir of powder containing active substance (which reservoir can be part of a dry powder inhaler disposed within the inhalation device) and a dispersion chamber. The dispersion chamber has a movable wall which varies the volume of the dispersion chamber between minimum and maximum volumes so as to draw powder containing active substance into the dispersion chamber. The movable wall is provided as a piston which when moved creates a negative pressure within the dispersion chamber. When dispersed, a patient can then inhale the powder containing active substance through a face mask or mouthpiece.
It is an aim of the present invention to ensure that powder containing active substance does not accumulate on internal surfaces of the inhalation device.
According to the present invention there is provided an inhalation device for providing a substance in a dispersed state, comprising: internal surfaces for ducting said substance and for containing said substance in a dispersed state; and a mechanism for creating vibrations in at least some of said internal surfaces so as to ensure that substance does not accumulate on the at least some of the internal surfaces.
According to the present invention there is also provided a method of ensuring that substance does not accumulate on internal surfaces of an inhalation device for providing said substance in a dispersed state, the method comprising the step of: creating vibrations in at least some of the internal surfaces so as to dislodge substance therefrom.
In this way, any small amounts of substance which deposit on the internal surfaces are dislodged into the air within the inhalation channel. Preferably, the vibrations are caused immediately prior to use, such that the dislodged substance is carried away, thereby minimizing the possibility of retention
REFERENCES:
patent: 2470296 (1949-05-01), Fields
patent: 2573918 (1951-11-01), McCuiston
patent: 3858583 (1975-01-01), Hallworth et al.
patent: 3948264 (1976-04-01), Wilke et al.
patent: 4524769 (1985-06-01), Wetterlin
patent: 4739754 (1988-04-01), Shaner
patent: 5082148 (1992-01-01), Dunning
patent: 5372128 (1994-12-01), Haber et al.
patent: 5437271 (1995-08-01), Hodson et al.
patent: 5522383 (1996-06-01), Calvert et al.
patent: 5694920 (1997-12-01), Abrams et al.
patent: 5758637 (1998-06-01), Ivri et al.
International Search Report.
Jennings Douglas
Jeppsson Magnus
Astra Aktiebolag
Lewis Aaron J.
Mitchell Teena
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