Evaluation of some parameters influencing the drug delivery from a dry powder inhalation device using an in vitro model of the horse airways.

The research article discusses an in vitro study conducted to determine how breathing pattern, air humidity, and device position might affect the effectiveness of a dry powder inhalation device, Inhalator M, in delivering a drug known as ipratropium.

Study Methodology

The researchers carried out an in vitro inhalation study with the following methods:

• The cascade impaction method (Andersen Sampler) was used. This is a technique of separating aerosol particles according to their sizes.
• This method was adapted to simulate nasal breathing, creating an artificial environment that imitates the airways in a horse.
• The drug being studied, ipratropium, was measured in the device, the artificial upper airways, and the various stages of the Andersen Sampler using liquid chromatography, a highly accurate analytical chemistry technique used to separate, identify, and quantify each component in a mixture.

Study Findings

Based on the evaluation of the inhalation device, the research paper pointed out several conclusions:

• The first stage of the Andersen Sampler represented the respirable fraction – the part of the drug ipratropium that can reach the lungs when inhaled.
• Stages 2 to 6 were considered the non-respirable fraction – these are the parts of the drug that do not make it to the lungs.
• The relative air humidity, air flow, and the position of the device significantly influenced the respirable fraction of ipratropium delivered through the Inhalator M device.
• On the other hand, the number of successive inhalations and the duration of each inhalation appeared to not affect the respirable fraction of the drug.

The findings of the study indicate that certain environmental and operational factors can impact the efficiency of aerosol drug delivery from a dry powder inhalation device. This knowledge can be vital in optimizing the use of such inhalation devices, especially for conditions like asthma where drug delivery efficiency is crucial.