Abstract
There is mounting evidence that a variety of drugs delivered as aerosols are likely to be of benefit in neonatal units. To avoid many of the problems associated with the use of jet nebulisers in ventilator circuits, a chamber was designed to be used in conjunction with a metered dose inhaler (MDI). The dimensions (4 cm x 11 cm) were chosen in an attempt to maximise drug delivery. In vitro studies were subsequently performed in order to determine the optimum operating conditions. Sodium cromoglycate delivered via this system was collected on a filter placed between the tip of an endotracheal tube and a model lung. The dose delivered was determined by means of an ultraviolet spectrophotometric assay. Using a Draeger Babylog 8000 ventilator it was found that drug delivery as maximised by actuating the device just before the inspiratory cycle when the chamber was placed adjacent to the endotracheal tube and by using a long (one second) inspiratory time. Under these conditions 1.5-2% of the original dose was deposited upon the filter at tidal volumes of 11-22 ml. When considered in terms of body weight this is many times the equivalent dose delivered to adults from an MDI. Effective drug delivery to the filter was confirmed using a radiolabelled aerosol. Radiolabelled studies delivering aerosol to the lungs of intubated rabbits demonstrated that deposition aerosol was distributed uniformly between lobes when corrected for the weight of each lobe. In conclusion, the device appears likely to deliver significant, reproducible quantities of drug to the lower respiratory tract while being simple to use.
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- Bush G. L. Aerosol delivery devices for the anesthesia circuit. Anesthesiology. 1986 Aug;65(2):240–240. doi: 10.1097/00000542-198608000-00040. [DOI] [PubMed] [Google Scholar]
- Cameron D., Arnot R., Clay M., Silverman M. Aerosol delivery in neonatal ventilator circuits: a rabbit lung model. Pediatr Pulmonol. 1991;10(3):208–213. doi: 10.1002/ppul.1950100314. [DOI] [PubMed] [Google Scholar]
- Cameron D., Clay M., Silverman M. Evaluation of nebulizers for use in neonatal ventilator circuits. Crit Care Med. 1990 Aug;18(8):866–870. doi: 10.1097/00003246-199008000-00015. [DOI] [PubMed] [Google Scholar]
- Crogan S. J., Bishop M. J. Delivery efficiency of metered dose aerosols given via endotracheal tubes. Anesthesiology. 1989 Jun;70(6):1008–1010. doi: 10.1097/00000542-198906000-00021. [DOI] [PubMed] [Google Scholar]
- Cummings J. J., D'Eugenio D. B., Gross S. J. A controlled trial of dexamethasone in preterm infants at high risk for bronchopulmonary dysplasia. N Engl J Med. 1989 Jun 8;320(23):1505–1510. doi: 10.1056/NEJM198906083202301. [DOI] [PubMed] [Google Scholar]
- Everard M. L., Clark A. R., Milner A. D. Drug delivery from holding chambers with attached facemask. Arch Dis Child. 1992 May;67(5):580–585. doi: 10.1136/adc.67.5.580. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fuller H. D., Dolovich M. B., Posmituck G., Pack W. W., Newhouse M. T. Pressurized aerosol versus jet aerosol delivery to mechanically ventilated patients. Comparison of dose to the lungs. Am Rev Respir Dis. 1990 Feb;141(2):440–444. doi: 10.1164/ajrccm/141.2.440. [DOI] [PubMed] [Google Scholar]
- Gay P. C., Patel H. G., Nelson S. B., Gilles B., Hubmayr R. D. Metered dose inhalers for bronchodilator delivery in intubated, mechanically ventilated patients. Chest. 1991 Jan;99(1):66–71. doi: 10.1378/chest.99.1.66. [DOI] [PubMed] [Google Scholar]
- Gomez-Del Rio M., Gerhardt T., Hehre D., Feller R., Bancalari E. Effect of a beta-agonist nebulization on lung function in neonates with increased pulmonary resistance. Pediatr Pulmonol. 1986 Sep-Oct;2(5):287–291. doi: 10.1002/ppul.1950020507. [DOI] [PubMed] [Google Scholar]
- Kao L. C., Durand D. J., Nickerson B. G. Effects of inhaled metaproterenol and atropine on the pulmonary mechanics of infants with bronchopulmonary dysplasia. Pediatr Pulmonol. 1989;6(2):74–80. doi: 10.1002/ppul.1950060204. [DOI] [PubMed] [Google Scholar]
- Motoyama E. K., Fort M. D., Klesh K. W., Mutich R. L., Guthrie R. D. Early onset of airway reactivity in premature infants with bronchopulmonary dysplasia. Am Rev Respir Dis. 1987 Jul;136(1):50–57. doi: 10.1164/ajrccm/136.1.50. [DOI] [PubMed] [Google Scholar]
- Silverman M. Aerosol therapy in the newborn. Arch Dis Child. 1990 Aug;65(8):906–908. doi: 10.1136/adc.65.8.906. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wilkie R. A., Bryan M. H. Effect of bronchodilators on airway resistance in ventilator-dependent neonates with chronic lung disease. J Pediatr. 1987 Aug;111(2):278–282. doi: 10.1016/s0022-3476(87)80087-2. [DOI] [PubMed] [Google Scholar]
- Yeh T. F., Torre J. A., Rastogi A., Anyebuno M. A., Pildes R. S. Early postnatal dexamethasone therapy in premature infants with severe respiratory distress syndrome: a double-blind, controlled study. J Pediatr. 1990 Aug;117(2 Pt 1):273–282. doi: 10.1016/s0022-3476(05)80547-5. [DOI] [PubMed] [Google Scholar]



