JET NEBULIZATION - INFLUENCE OF DYNAMIC CONDITIONS AND NEBULIZER ON NEBULIZATION QUALITY - APPLICATION TO THE ALPHA-1 PROTEASE INHIBITOR

The use of nebulisers lacks standardisation, which may account for cer tain inefficiency. As part of a study of alpha 1 protease inhibitor (a lpha 1 PI) nebulisation for pulmonary administration, we studied the i nfluence of technological parameters that is to say the nebuliser and the dynamic conditions (airflow and pressure) on nebulisation quality. The quality of nebulisation is evaluated by measurement of the percen tage of droplets below 5.79 mu m, the quantity of alpha 1 PI nebulised , the quantity of alpha 1 PI likely to reach the lungs and nebulisatio n time. The use of different dynamic conditions results in variable ne bulisation quality. Depending upon the power of the compressor and the type of nebuliser, drug delivery varies. The association of high airf low and high pressure improves the respirable fraction and compliance by decreasing nebulisation time. Although droplet size is a commonly u sed parameter, it is not sufficient to forecast efficiency. It must be associated with the quantity of drug nebulised and, to a lesser exten t, nebulisation time. The nebuliser is also to be taken into considera tion. The characteristics of the constituent nebuliser elements, that is to say liquid and air tube orifices, size and shape of the reservoi r, shape and position of the impartion system, are preponderant on neb ulisation quality. (C) 1997 Elsevier Science B.V.