The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts

ALBUTEROL DELIVERY BY INTRAPULMONARY PERCUSSIVE VENTILATION (IPV®)AND A CONTINUOUS JET NEBULIZER IN A HEATED WIRE VENTILATOR CIRCUIT UTILIZING A PEDIATRIC VENTILATOR IN-VITRO MODEL

Randy Willis1, Ariel Berlinski2,3



Background: Aerosol delivery during mechanical ventilation depends on several factors. We use heated wire ventilator circuits (HWVC) (Fisher-Paykel, Auckland, NZ) with our ventilators (Servo~i, Maquet, Solna, Sweden). This limits the positions where a nebulizer can be placed. We compared albuterol output from a continuous jet nebulizer and an IPV (Percussionaire, Sandpoint, ID) nebulizer inline in a HWVC utilizing pediatric ventilator settings at different VTs, positions and percussion settings (IPV).

Methods: 3 IPV & 3 Salter nebulizers (Salter Labs, Arvin, CA)were studied. IPV units were operated with central oxygen at 50 PSI, drive pressure of 25 cm H2O for 15 minutes. Salter nebulizers were operated at 6 lpm with an external gas source for 5 minutes. 5 mg of albuterol sulfate diluted with saline to 3 ml(Salter) or 10 ml(IPV). The Servo was operated in PRVC mode, RR 20,PEEP 5 cm H2O,FiO2 0.4,IT 0.75 seconds, inspiratory rise 0.15 seconds,flow trigger 3 and heater 37±1.5 C. The HWVC was connected to a 5.5 cuffed ETT followed by a lung model with a deposition filter interposed between them. The following variables were studied: VT (100 vs. 200 ml); position in the circuit [Wye (@Y) vs.humidifier (@H)], and percussion settings (easy vs.hard). PIP (cm H2O) was recorded during IPV operation. IPV was connected at the Wye with its own special adapter. VTs were adjusted when using the Salter. Albuterol was measured by spectrophotometry at 276 nm. Statistical analysis was performed with 3 way ANOVA. A p value of 0.05 was considered significant.

Results: (see table)

Conclusion: IPV is inefficient to deliver albuterol in a HWVC using pediatric settings. Different types of nebulizers have different optimal operating conditions. Pressures during IPV therapy are higher at higher VTs and when placed at the Wye.