[Inhalation antibiotherapy]

[Treatment of non-cystic fibrosis bronchiectasis]

Bronchiectasis is currently growing in importance due to both the increase in the number of diagnoses made as well as the negative impact that its presence has on the baseline disease that generates it. A fundamental aspect in these patients is the colonization and infection of the bronchial mucous by potentially pathogenic microorganisms (PPM), which are the cause in most cases of the start of the chronic inflammatory process that results in the destruction and dilatation of the bronchial tree that is characteristic in these patients. The treatment of the colonization and chronic bronchial infection in these patients should be based on prolonged antibiotic therapy in its different presentations. Lately, the inhaled form is becoming especially prominent due to its high efficacy and limited production of important adverse effects. However, one must not overlook the fact that the management of patients with bronchiectasis should be multidisciplinary and multidimensional. In addition to antibiotic treatment, the collaboration of different medical and surgical specialties is essential for the management of the exacerbations, nutritional aspects, respiratory physiotherapy, muscle rehabilitation, complications, inflammation and bronchial hyperreactivity and the hypersecretion that characterizes these patients.

[Administration of anti-infective agents through the inhaled route]

OBJECTIVE

To report the doses of inhaled anti-infective agents described in the literature for both the adult and paediatric population. In the case of anti-infective agents which were not approved for inhaled administration, to propose the optimum manner in which these should be prepared in order to achieve osmolality and pH values as similar as possible to physiological values.

METHOD

A search was carried out of Pubmed (between 1960 and 2005) for each of the anti-infective agents using the words "inhalation OR inhaled OR aerosol OR aerosolized OR nebulized". We also consulted text books, Micromedex and the technical specifications of the pharmaceutical products. Nebulised solutions were prepared using the drugs for which information was found. The drugs approved for inhaled administration were prepared according to the manufacturers recommendations. For anti-infective agents which were not approved for inhaled administration, the raw materials and the branded drug products for intravenous administration available at our hospital were diluted using physiological saline solution and/or water for injection up to a final volume of 4-5 ml. The osmolality and pH values of all the solutions were measured. The optimum form of preparation was considered to be one with values as close as possible to between 150 and 550 mOsm/kg for osmolatity osmolality and 7 +/- 0.5 for pH.

RESULTS

Information about doses of 18 inhaled anti-infective agents was found (12 antibiotics, 5 antifungals and 1 antiviral); paediatric doses were described in 9 of these. Three of the anti-infective agents reviewed were approved for inhaled use in adult patients and four in paediatric patients. Of the 48 recommendations for dilution suggested for administration, two had an osmolality > 1,100 mOsm/kg and 5 an osmolality of < 100 mOsm/kg. Two dilutions had a pH > 8 and 14 a pH < 5.

CONCLUSIONS

There is limited literature regarding the doses of anti-infective agents for inhaled administration. The majority of anti-infective agents are not approved for inhaled administration. The dilution of the raw material or proprietary drugs with water or physiological saline solution for intravenous administration achieved solutions with appropriate osmolality in the majority of cases. Some of the solutions have extreme osmolality and/or pH levels, implying that it is reasonable to expect a greater risk of bronchospasm.