Scireq flexivent, User Manual, Page: 24 / 86

22
1.4.5.1 STANDARDIZING VOLUME HISTORY
A subject’s volume history affects mechanics measurements. Ventilation parameters (e.g. tidal
volume, I/E ratio) are set in the software to ensure that all subjects in a study are ventilated in a
similar manner. In addition, the Deep Inflation perturbation is commonly used to re-set or
standardize volume history. This is especially true in dose response studies (in which the Deep
Inflation may be used to help subjects return to baseline before subsequent doses are
administered) and imaging studies (in which the Deep Inflation is used to ensure consistent
inflation prior to image acquisition).
1.4.6 INTERCHANGEABLE MODULES
As mentioned in section 1.3, the
flexiVent
FX piston/cylinder set and valves that create the
ventilator compartment are mounted on the portion of the system called the module. There are
five modules currently available. Each module is designed to minimize its inherent resistance
which permits the highest precision mechanics measurements. The piston/cylinder set size
determines whether or not the system is appropriate for work with a given subject, so the
system can be easily adapted for a wide range of subject sizes. Furthermore, one base unit may
be used with a variety of subjects by incorporating additional modules. Refer to Table
A-2 for
module specifications, including estimates for subject weight ranges.
1.4.7 INTEGRATING A NEBULIZER
The Aerogen Aeroneb ultrasonic nebulizer can be integrated with the
flexiVent
FX in order to
deliver aerosols to the subject. The parameters of aerosol production are set in the software,
which allows for precise control of the aerosol delivery. Specially designed adapters allow tight
integration of the nebulizer to minimize aerosol rainout. The flow pathways within the adapters
are also designed to minimize the addition of volume to the ventilator compartment for
nebulizer integration. Refer to section
4.2 for additional details about the nebulizer. Refer to the
flexiWare
user manual for additional details on software settings to control the nebulizer as
well as nebulizer output rate and rainout characterization.