2002 OPEN FORUM Abstracts
MiniHEART CONTINUOUS NEBULIZER ATTACHMENT FOR IN-LINE VENTILATOR AEROSOL MEDICATION DELIVERY
Idichandi Idicula MS, RRT, Bob Estetter RRT, Anthony Dal Nogare MD, Parkland Health & Hospital System, Dallas, Texas
Introduction: Aerosolized bronchodilator has been administered continuously using MiniHEART Continuous Nebulizer to mechanically ventilated patients who are suffering from bronchospasm.
To our knowledge, the
ideal location to attach the nebulizer in the circuit to achieve the most deposition
of aerosolized particle in the lower airways is not currently identified. We
hypothesized that attaching a MiniHEART Continuous Nebulizer between the humidifier
outlet and the inspiratory portion of the ventilator circuit would significantly
improve delivery of aerosolized medication.
Methods: A filter to collect the deposition of the aerosolized albuterol was connected to the circuit wye with a 200 cc (24inches) corrugated tubing and a # 8 endotracheal tube. The filter was then attached to a Michigan Lung Model (compliance 35 cm H2O) using a 100 cc corrugated tubing. The model was ventilated sequentially with two volume ventilators, TBird AVS and Bear 1000tes. Each ventilator was set on A/C, RR 15, Vt 600 cc, FiO2 21%, PEEP +5 cm H2O, I:E ratio 1:4, and the Bias Flow of 10 L/M. The MiniHEART Continuous Nebulizer, filled with Albuterol Sulfate for Inhalation 0.5 %, was connected to the ventilator circuit prior to the wye. Medication was nebulized continuously at 2 L/M (as per manufacturer?s recommendation) for 20 minutes and samples were collected. The sample collection was repeated with the MiniHEART Nebulizer attached between the humidifier and the ventilator circuit. Samples (filters with absorbed medication) were removed from the circuit following each nebulization and placed in a sterile container with 8mls of 70 % ethanol. The filters remained in ethanol for approximately 8 hours. A sample of 0.7mls from each container was then analyzed using a spectrophotometer at 278 nanometers. The optical densities of each sample were then plotted on a graph of known albuterol concentrations to convert the data to mg albuterol/ml and results were compared. Results:
|Vent Settings A/C, f 15 B/M, 600ml, 21%, PEEP 5, I:E 1:4||Nebulizer attached at the wye prior to proximal airway||Nebulizer attached at the humidifier prior to the ventilator circuit|
Deposition: 1.8 mg
Deposition: 10.8 %
Deposition: 4.16 mg
Deposition: 25 %
Flow: 63 L/M
Bias Flow: 10 L/M
Range: 1.128 1.329
Deposition: 1.568 mg
Deposition: 10.7 %
Deposition: 4.0 mg
Deposition: 27 %
Discussion: Our data suggest that the delivery of aerosolized medications using MiniHEART Continuous Nebulizer can be significantly increased by attaching the Nebulizer to the humidifier outlet prior to the ventilator tubing connection. Further investigations are needed to identify ways of improving the delivery of aerosolized medication.