Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Chapter 3 Administration of Aerosolized Agents

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Three Main Uses of Aerosol Therapy  Humidification of dry inspired gases  Improved mobilization and clearance of respiratory secretions  Delivery of aerosolized drugs to the respiratory tract

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Physical Principles of Inhaled Aerosol Drugs  Aerosol particle size distributions  Count mode  Count median diameter (CMD)  Mass median diameter (MMD or MMAD)  Geometric standard deviation (GSD)  Measurement of particle size distributions  Aerodynamic diameter

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Physical Principles of Inhaled Aerosol Drugs  Particle size and lung deposition  Fine particle fraction  Particle size and therapeutic effect Particles >10 microns Particles >10 microns Particles 5 to 10 microns Particles 5 to 10 microns Particles 2 to 5 microns Particles 2 to 5 microns Particles 0.8 to 3 microns Particles 0.8 to 3 microns

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Physical Principles of Inhaled Aerosol Drugs  Mechanisms of deposition  Inertial impaction  Gravitational settling  Diffusion (Brownian motion)  Effect of temperature and humidity  Hygroscopic increase in MMAD

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Ultrasonic nebulizers  Small particle aerosol generator (SPAG)

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Small volume nebulizers (SVNs)  Dead volume  Filling volume and treatment time  Effect of flow rate  Type of power gas  Type of solution  Development of various nebulizer designs

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Metered dose inhalers (MDIs)  Technical description  Correct use

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Metered dose inhalers  Factors affecting MDI performance Loss of dose Loss of dose Shaking the canister Shaking the canister Timing of actuation intervals Timing of actuation intervals Open-mouth versus closed-mouth use Open-mouth versus closed-mouth use Loss of prime Loss of prime Storage temperature Storage temperature

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Metered dose inhalers  Breath-actuated inhalers The Autohaler The Autohaler Other devices Other devices  Hydrofluoroalkane (Nonchlorofluorocarbon) propellants Equivalence and safety Equivalence and safety Improved drug delivery with HFA formulation Improved drug delivery with HFA formulation

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  MDI reservoir devices  Reservoir devices  Design variables  Electrostatic charge  Size  Other MDI auxiliary devices

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Aerosol Devices for Drug Delivery  Dry powder inhalers (DPIs)  Inspiratory flow rate  Humidity  Clinical efficacy

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Recommendations based on clinical evidence  Aerosol delivery of short-acting β 2 agonists in the ER  Aerosol delivery of short-acting β 2 agonists in the hospital  Intermittent versus continuous nebulizer delivery of β 2 agonists

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Recommendations based on clinical evidence (continued)  Aerosol delivery of β 2 agonists to patients receiving mechanical ventilation  Aerosol delivery of short-acting β 2 agonists for asthma in the outpatient setting

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Recommendations based on clinical evidence (continued)  Inhaled corticosteroids for asthma  β 2 Agonists and anticholinergic agents for COPD  Device selection

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Lung deposition and loss patterns with traditional aerosol devices  MDI (CFC) = 8.8% deposition  MDI (HFA) = 53% deposition  MDI (CFC) with spacer = 14.8% deposition  SVN = 12.4% deposition  DPI = 14.8 to 27.7% deposition

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Equivalent doses among device types  Lung deposition with newer aerosol devices  Clinical equivalence of MDIs and SVNs  Age guidelines for the use of aerosol devices

Mosby items and derived items © 2008, 2002 by Mosby, Inc., an affiliate of Elsevier Inc. Clinical Application of Aerosol Delivery Devices  Patient-device interface  Administration by intermittent positive-pressure breathing  Face mask administration  Endotracheal tube administration