aerosol

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aerosol

 [ār´o-sol″]
a colloid system in which solid or liquid particles are suspended in a gas, especially a suspension of a drug or other substance to be dispensed in a cloud or mist. See also aerosol therapy.
aerosol clearance removal of particles that have been deposited in the respiratory tissues. Clearance may occur by ciliary transport, by phagocytosis, by encapsulation and immobilization in a deposit of fibrous tissue (in which case the particles remain in the body), and by dissolving in tissue fluid and subsequently diffusing into the general circulation where the particles are metabolized.
aerosol deposition the depositing of aerosol particles onto a nearby surface, especially deposition or retention of the particles within the respiratory system. Closely related to aerosol penetration and affected by the same factors.
aerosol penetration the maximum distance aerosol particles can be carried into the respiratory tract by inhaled air. Depth of penetration increases as particle size decreases. Factors affecting where aerosol particles will be deposited and how deeply they can penetrate are: gravity, kinetic activity of gas molecules, inertial impaction, physical nature of the particle, and the ventilatory pattern.
aerosol therapy use of an aerosol for respiratory care in the treatment of bronchopulmonary disease. The major purpose of this is the delivery of medications or humidity or both to the mucosa of the respiratory tract and pulmonary alveoli. Agents delivered by aerosol therapy may act in a number of ways: (1) to relieve spasm of the bronchial muscles and reduce edema of the mucous membranes, (2) to render bronchial secretions more liquid so that they are more easily removed, (3) to humidify the respiratory tract, and (4) to administer antibiotics locally by depositing them in the respiratory tract.

Physical and chemical substances used as medical aerosols include drugs that act as bronchodilators and decongestants, such as epinephrine, ephedrine, isoproterenol, atropine, and the steroids. Wetting agents administered as aerosols to render the bronchial secretions more liquid include tyloxapol and acetylcysteine. The choice of antibiotics to be given as aerosol therapy is determined by the patient's specific condition and the preference of the health care provider. Most standard antibiotic drugs are available in aerosol form.

In general, the respiratory therapist is concerned with factors that affect how deeply aerosol particles can penetrate into the bronchial tract and the locations at which these particles are deposited on the bronchial mucosa and alveolar tissues. Depth of penetration is affected by particle size. Particles as large as 100 μm and as small as 5 μm are trapped in the nose. Those 2 to 5 μm in size are deposited somewhere in the respiratory tract proximal to the alveoli. Deposition in the alveoli is 90 to 100 per cent for particles 1 to 2 μm in size.

Because aerosol particles are so small, they present the phenomenon of brownian movement as they are bombarded by the molecules of the gas in which they are carried. The velocity with which these particles move about directly affects their diffusion and deposition onto nearby surfaces. Thus the type of aerosol generator used in aerosol therapy is of primary importance.

Another factor affecting penetration and deposition of aerosol particles that should be of concern to respiratory therapists and other members of the health team who are teaching patients the techniques of effective aerosol therapy is that of ventilatory pattern. The ideal pattern of breathing for optimum delivery of aerosol particles is that of slow, moderate deep breathing with breath holding at the end of each inhalation.

aer·o·sol

(ār'ō-sol),
1. Liquid or particulate matter dispersed in air, gas, or vapor in the form of a fine mist for therapeutic, insecticidal, or other purposes.
2. A product that is packaged under pressure and contains therapeutically or chemically active ingredients intended for topical application, inhalation, or introduction into body orifices.
[aero- + solution]

aerosol

/aer·o·sol/ (ār´o-sol) a colloid system in which solid or liquid particles are suspended in a gas, especially a suspension of a drug or other substance to be dispensed in a fine spray or mist.

aerosol

[er′əsol′]
Etymology: Gk, aer; L, solutus, in dissolved
1 nebulized particles suspended in a gas or in air.
2 a pressurized gas containing a finely nebulized medication for inhalation therapy.
3 a pressurized gas containing a nebulized chemical agent for sterilizing the air of a room.

aerosol

Epidemiology A particulate suspension of infectious agents which may remain pathogenic for long periods of time; a fine mist or spray containing minute particles from soil, clothes, bedding or floors when moved, cleaned or blown by wind; aerosolized material includes fungal spores–infective agents themselves–bits of infected feces, or particles of dirt or soil that have been contaminated with a pathogen. See Droplet nuclei Occupational medicine A suspension of particles in air. See Acid aerosol, Airborne transmission, Inhalant,  Flammable aerosol, Sclerosol® (talc powder) intrapleural aerosol Therapeutics A suspension or dispersion of fine particles, ranging 10–6-10–9 in diameter, of a solid or liquid in a gas, which is atomized into a fine mist for inhalation therapy, or for a nebulizer and inhaled.

aer·o·sol

(ār'ō-sol)
1. Liquid or particulate matter in the form of a stable suspension for therapeutic, insecticidal, or other purposes, including bioterrorism and bioweapons; forms include dusts, smokes, mists, clouds, fumes, and fogs.
2. A product that is packaged under pressure and contains therapeutically or chemically active ingredients intended for topical application, inhalation, or introduction into body orifices.

aerosol

A suspension of very small droplets of a liquid or particles of a solid, in air. A range of drugs can be given in aerosol form for inhalation. Many sufferers from ASTHMA rely heavily on inhalers or aerosol dispensers.

aerosol

pressurized therapeutic agent forming a fine powder on release

aer·o·sol

(ār'ō-sol)
1. Invisible airborne particles dispersed into the surrounding environment by dental equipment (e.g., handpieces, electronic instruments). Microorganisms in aerosols have been shown to survive up to 24 hours.
2. Liquid or particulate matter dispersed in air, gas, or vapor in the form of a fine mist for therapeutic, insecticidal, or other purposes.
3. A product that is packaged under pressure and contains therapeutically or chemically active ingredients intended for topical application, inhalation, or introduction into body orifices.
[aero- + solution]

aerosol (er´əsôl),

n 1. the suspension of materials in a gas or vapor (e.g., saliva vaporized in air-water spray from a high-speed handpiece).
2. a substance dispensed as a constituent of a gas or vapor suspension.

aerosol

a colloid system in which solid or liquid particles are suspended in a gas, especially a suspension of a drug or other substance to be dispensed in a cloud or mist.

aerosol clearance
removal of particles that have been deposited in the respiratory tissues. Clearance may occur by ciliary transport, by phagocytosis, by encapsulation and immobilization in a deposit of fibrous tissue (in which case the particles remain in the body), and by dissolving in tissue fluid and subsequently diffusing into the general circulation where the particles are metabolized.
aerosol deposition
the depositing of aerosol particles onto a nearby surface, especially deposition or retention of the particles within the respiratory system. Closely related to aerosol penetration and affected by the same factors.
aerosol penetration
the maximum distance aerosol particles can be carried into the respiratory tract by inhaled air. Depth of penetration increases as particle size decreases. Factors affecting where aerosol particles will be deposited and how deeply they can penetrate are: gravity, kinetic activity of gas molecules, inertial impaction, physical nature of the particle, and the ventilatory pattern.
aerosol therapy
nebulization; delivery of a therapeutic agent as a fine mist or spray to the mucociliary layer of the respiratory tract.