The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts

EFFECTS OF THE WATER CHAMBER LEVEL ON DELTA PRESSURE AND MEAN AIRWAY PRESSURE ON THE 3100A HIGH FREQUENCY OSCILLATOR.

Jared B. Rice, Chad Weagraff, Timothy Myers; Pediatric Respiratory Care, University Hospitals - Rainbow Babies and Children’s Hospital, Cleveland, OH

Background: The Sensormedics 3100A High Frequency Oscillatory Ventilator (Viasys Healthcare) utilizes a rapid rate and small tidal volume ventilation concept. Oxygenation and ventilation are managed by manipulating the mean airway pressure (MAP) and delta P pressure (ΔP). The 3100A uses a low-compliance circuit with heated pass-over humidification system. The degree of humidity achieved is dependent on time of exposure and surface area of gas/water contact. The purpose of this study was to determine if changes in humidification chamber water levels has an effect on MAP or ΔP. Methods: The3100A HFOV was calibrated with a HFOV circuit (CareFusion 38” Flexible Patient Circuit) and humidifier canister connected to an Ingmar Neonatal Demonstration Lung Model (Ingmar Medical, Pittsburgh, PA) with a compliance set at 2 mL/cm H20. The 3100A was set at the following parameters: bias flow 20 lpm, power 3, Hz 12, and MAP 15 cm H2O. MAP and ΔP were measured using the airway pressure line located at the patient connection. MAP and ΔP were measured under three conditions: humidification chamber empty, half full (150 mL), or full (300 mL) with sterile water. Data was recorded for MAP and ΔP measurements for the three describe humidification water levels. MAP and ΔP pressure differences at different water levels were compared using a paired t-test with a statistical significance set at p< 0.05. Results: Means pressures and standard deviations are reported in the table below. P values measured for conditions were 0.001. Conclusions: A change in water level in the humidification chamber during simulated HFOV had no significant impact on desired pressure targets for ΔP or MAP. Sponsored Research - None