2004 OPEN FORUM Abstracts
SYNCHRONIZED MINIMUM MANDITORY VENTILATION WITH THE Pneupac paraPAC ‘medic’200D VENTILATOR.
Mark Rose RRT, Roger Smith RRT, William
R. Watson BMET, Mike Trevino RRT, Gary Weinstein MD FCCP,
Presbyterian Hospital of Dallas.
BACKGROUND:
Transporting ventilated patients in today’s environment,
presents unique challenges to even the most seasoned respiratory
therapists. The Pneupac paraPAC ‘medic’ 200D ventilator
is designed to provide spontaneous breathing without stacking of
breaths via Synchronized Minimum Mandatory Ventilation (SMMV).
According to the manufacturer; “when ‘CMV/Demand’
is selected, the ventilator cycles at the set frequency but if a
spontaneous breath is taken during an exhalation phase then this is
taken from an internal demand valve. If breathing is at an adequate
level for an adult, cycling will be inhibited as long as this
breathing level is maintained. If breathing becomes inadequate, CMV
will be restored, synchronized with the last breath.” The
purpose of this study is to determine the accuracy of this
application.
METHODS:
A two compartment lung model, (Michigan Instruments 5600i), was used
to simulate spontaneous respirations as described by (Katz et al,
Chest, 88, 4, 1985). A properly calibrated Fluke Vt Plus HF Gas Flow
Analyzer was utilized to verify volumes, flows and pressures. The
200D ventilator settings were as follows; ‘CMV/Demand’
mode, f:8bpm, Vt:800cc with the air mix on. The Michigan Instruments
Breath Simulation Module was set to deliver a measured f:12bpm and
tidal volumes ranging from 80-1000cc.
RESULTS:
Spontaneous tidal volumes of 80-100cc were virtually ignored by the
200D. Spontaneous volumes ranging from 200-453cc were supported,
however, no appreciable stacking of the mechanical breath nor cycle
time interference was noted. CMV ventilation from the 200D was
inhibited at a spontaneous Vt:470cc and remained inhibited with
subsequent increases to as high as Vt:1000cc. During our test, we
found that spontaneous tidal volumes above 1000cc produced erratic
inspiratory flow, indicating that we were nearing its peak flow
capabilities.
CONCLUSION:.
It should be noted that in patients that have high spontaneous tidal
volumes, this ventilator may not meet their individual flow needs.
The manufacturer recommends sedation for that particular patient
population. This ventilator offers respiratory therapists the
capability of effectively transporting critically ill ventilated
patients to and from the myriad of tests ordered in today’s
critical care environment. The Pneupac paraPAC ‘medic’
200D transport ventilator, when used according to the manufacturer’s
recommendations, appears to perform as expected.