2004 OPEN FORUM Abstracts
AN IN VITRO INVESTIGATION OF TWO TECHNIQUES FOR NEBULIZER DELIVERY IN SPONTANEOUSLY BREATHING PEDIATRIC SUBJECTS
D Restrepo MD RRT, Stephen K. Dickson MS RRT, Joseph L Rau PhD
RRT, Douglas S Gardenhire MS RRT. Department of Cardiopulmonary Care
Sciences. Georgia State University. Atlanta, Georgia.
The application of a mask and the maintenance of a tight seal during aerosol therapy in the infant and toddler can be challenging. An alternative technique used in the pediatric group for the delivery of aerosol is via “blow-by” with a T-piece.
PURPOSE: The purpose of this study was to compare the inhaled drug mass delivered via a standard pediatric aerosol mask versus a T-Piece, and measure the effect of increasing distance on inhaled drug mass with each device.
METHODS: An in vitro simulation of spontaneous breathing in a toddler was used. Five nebulizer samples were used with both a standard pediatric aerosol mask and a T-piece capped at one end for aerosol delivery at 0, 1, and 2 centimeters from a filter placed at the test lung inlet. The inhaled drug mass was collected on the filter, and analyzed by spectrophotometer. A randomized block factorial analysis of variance (ANOVA) for repeated measures was performed for devices and distances, with an alpha level of 0.05. Follow-up comparisons were performed using a paired t-test for drug delivery between devices at each distance, as well as between distances and a Bonferroni adjusted probability was calculated for each test.
RESULTS: Randomized block factorial ANOVA for device and distance indicated a statistically greater inhaled drug mass with T-piece compared to mask (p < 0.01) and significant decrease as distance increased (p < 0.01). The Bonferroni adjusted probabilities for inhaled drug mass with mask vs. T-piece indicated a statistically significant difference between the mask and T-piece performance at 1 and 2 centimeters. Tests for the T-piece did not show a statistically significant change in inhaled drug mass with distance changes (p > 0.05). Tests for the mask indicated a statistically significant difference in inhaled drug mass between zero and one and zero and two centimeters, but no statistically significant difference between one and two centimeters.
CONCLUSION: Our data suggests that the inhaled drug mass delivered via a T-piece is greater than that seen with a standard pediatric aerosol mask. The use of a T-piece instead of the standard aerosol mask with conventional nebulization is likely to optimize the inhaled drug mass for pediatric patients.