ch 36

is a suspension of solid or liquid particles in gas. One of the parimary functions of the upper airway and respiratory tract is to protect the lungs from invasion by these aersols..

Is defined as the mass of fluid or drug contined in aerosl produced by a nebulizer.

deposition is the settling of particles (atoms or molecules) or sediment from a solution, suspension and mixture or vapor onto a pre-existing surface.

describes the mass of drug leaving the mouthpiece of a neublizer or inhaler as a aerosol.

devices that physically disperse matter into small particles and suspend them into a gas

the ratio between the dosage of a drug that causes a lethal effect and the dosage that causes a therapeutic effect.

central tendency

laser diffraction

describes the variability of particle sizes in an aerosol distrubition set at one standard eviation (SD) above or below the median (15.8% and 84.13% respectivaely)

Most aerosols found in nature and used in respiratory care are composed of particles of different sizes. The greater the GSD, the wider the range of particles sizes and the more heterodisperse the aerosol.

Aerosols consisiting of particles of similiar size are referred to as monodisperse aerosols. Nebulizers that produced monodisperse aerosols are used mainly in laboratory research and in nonmedical industries.

is the amount of drug inhaled.

THe proportion of the drug mass in partickles that are small enough (fine-partickle fraction) to reach teh lower respiratory tract is the respirable mass.

occurs when suspended particles in motion collide with and are deposited on a surface. Because interia involves both mass and velocity, the higher the flow of a gas stream, the greater the tendency for particles to impact and be deposited in hte airways.

occurs when aerosol particles settle out of suspension and are deposited owing to gravity. The greater the mass of the particle, the faster it settles.

The process by which an aerosol suspension cahnges overtime

Aerosol particles can change size as a result of either evaportation or " "

drug is tagged with a radioactive substance (such as technetium) aeroslized, and inhaled

is a material that is used to move ("propel") an object.

A drypowder inhaler (DPI) is typically a breath-actuated dosing system.

is simply a surface on which large particles impact and fall out of suspension whilie smaller particles rmeain in suspension, reducing the size of particles remaining in the aerosol.

or dead volume, is the medication that remains in the SVN after the device runs dry.

entrain air through the nebulizer during inspiration

that reduce or elminate aerosol generation during the patient's expiratory phase.

have medication reservoir's less than 10ml