Breath operated inhaler

BREATH OPERATED INHALERS AND OTHER DEVICE ENHANCEMENTS... 

Very young children and older people have significant difficulty coordinating their actuation of the device with breathing in Ref.. Patients who have this coordination difficulty can either be supplied with a dry powder inhaler (where the inspiration through the device is also responsible for the release and aero-solization of the powdered drug so that coordination is no longer an issue), or they may be be prescribed a Breath Operated Inhaler (BOI). 

Hardy J, Jasuja A, Frier M, Perkins A. A small volume spacer for use with a breath-operated pressurised metered dose inhaler. Int J Pharm 1996 142 129-133. 

Figure 2 presents a snggestion for the choice of device in varions age groups. In brief, nebnUzers are rarely indicated for maintenance treatment. pMDI and spacer with face mask or mouthpiece is the preferred device for maintenance treatment until the child is sufficiently mature to reliably use a dry-powder inhaler (DPI) or breath-operated pMDI (12). 

Pover G, Langdon C, Jones S, Fidler C. Evaluation of a breath operated powder inhaler. J Int Med Res 1988 16 201-203. 

Phosgene [75-44-5] M 98.9, b 8.2 /756mm. Dried with Linde 4A molecular sieves, degassed and distilled under vacuum. This should be done in a closed system such as a vacuum line. HIGHLY TOXIC, should not be inhaled. If it is inhaled operator should lie still and made to breath ammonia vapour which reacts with phosgene to give urea. 

Results clearly indicated effects of diesel exhausts from different engine operating conditions on the cells already after 1 h of exposure. However, a 1-h continuous exposure to a therapeutic aerosol is probably of limited clinical relevance. To study the effect of drugs administered by typical pharmaceutical single-dose inhalers (MDI, DPI) effective deposition of one puff within the time of one breathing maneuver ( 5 s) is probably more relevant. 

All operations should be carried out with good ventilation and contact with eyes and skin should be avoided. In case of eye contact, the eyes should be flushed with water for 15 min and a physician should be consulted. Soap and water should be used to wash azobisnitriles from skin. If these compounds are inhaled, particularly the decomposition products of Vazo 64, the victim should be removed to fresh air and oxygen should be administered. If the victim is not breathing, cardiopulmonary resuscitation should be administered. A physician should be called in either case. Small quantities of waste Vazo should be disposed of by incineration, preferably by dissolving first in a waste liquid. Large quantities of waste Vazo should be returned to the manufacturer for disposal. 

The Autohaler has been devised as a breath-activated pressurised inhaler system because of the difficulty experienced by some patients in coordinating manual operation of an aerosol with inhalation. The Autohaler is activated by the negative pressure created during the inhalation phase of respiration and is specifically designed to respond to shallow inhalation in those with restricted pulmonary capacity. 

Operative Period.—As soon as this stage is reached, the gas is removed. The pulse at once becomes slower and fuller the respiration also recovers rapidly and the asphyxial symptoms disappear. The anesthesia lasts some twenty-two to thirty seconds after the gas is removed and it is during this period that the operation must be performed. The total time between the beginning of the administration and complete recovery is therefore one hundred to one hundred and twenty seconds. The duration of the after-anesthesia increases with the duration of the administration. This may be prolonged to several minutes by giving the patient an occasional breath of pure air (every fifth inhalation) or by admitting a little air into the mask. The admission of air, however, makes the anesthesia uneven and unsatisfactory. 

Riker Laboratories, now 3M Healthcare, invented the pressurised metered dose inhaler (MDI) in 1955 when they combined the atomising power of CFCs and a metering valve design. The great majority of valves still use this basic retention valve principle, and hence pressurised MDIs (pMDIs) are all similar in appearance and operation when used with a standard actuator in the normal press and breathe manner. 

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