2002 OPEN FORUM Abstracts
Effects of Positioning on the Reliability and Effectiveness of the Vortran Automatic Resuscitator
Mellor, BS RRT, Dean Holland, RRT, Robert Estetter, RRT,
Jackie Boynton, RRT,
Kenneth Hawkins, BS RRT
Parkland Health and Hospital
System, Dallas, Texas
Department of Respiratory Care
Introduction: The Vortran Automatic Resuscitator (VAR) (Vortran Medical Technology 1, INC. Sacramento, CA) is a single patient, multiple-use resuscitator. Medical literature suggests that the VAR provides reliable and consistent ventilatory support. We will evaluate the effects of positioning on the reliability and effectiveness of the VAR.
Methods: Ten VAR's (Model RC with monometer) were divided into two groups each consisting of five VAR's. Each VAR was evaluated using Michigan Instruments adult lung model interfaced with PneuView software (Michigan Instruments, INC. Santa Monica, CA). Group A was positioned horizontally as illustrated in the VAR operation manual while Group B was positioned vertically. All VAR's were connected to the lung model with a # 8 endotracheal tube (ETT) and an adult hygroscopic condenser humidifier (Allegiance Healthcare, McGaw Park, IL). Lung compliance was fixed at 60cc/cmH20 throughout the evaluation. Each VAR was set with 100% FIO2 entrainment and connected to a high-flow oxygen flowmeter set at a Flow Rate (FR) 30 lpm. VAR's were then set to deliver Peak Inspiratory Pressure (PIP) 20 and Respiratory Rate (RR) 12. Minute Volume (MV), Inspiratory-time (I-time), PIP, and RR data was collected in ten minute intervals for a period of 24 hours. Results were posted in a Trend Report via PneuView software.
Results: In Group A, three out of five VAR's failed to trigger for the duration of the 24 hour evaluation period. One VAR failed at two hours and another failed at three hours; both failed to trigger again for the remainder of evaluation. The third malfunctioned at one hour and forty minutes. Failure consisted of the VAR reaching PIP and then fluttering at PIP for ten minutes. It then resumed normal operation when at six hours it failed to trigger for the duration of the evaluation. In Group B, all five of the VAR's triggered throughout the duration of the 24 hour evaluation. Four of the five VAR?s maintained parameters set at initiation of the evaluation. The fifth VAR maintained parameters for 23 hours, the RR then decreased from 12 to 6.8 for a period of 30 minutes. It should be noted that the fifth VAR completed the evaluation period. In the table below is a summary of data collected and analyzed by PneuView software.
|Parameter||GROUP A - Range||GROUP B - Range|
|PIP (cmH20)||4.4 - 23.5||19.2 - 21.8|
|MV (L/min)||0.0 - 35.5||8.1 - 13.9|
|RR (bpm)||0.0 - 64.5||6.8 - 12.8|
|I-time (sec)||0.7 - 5.0||2.3 - 2.6|
Experience: Our initial study was designed to evaluate the effectiveness of the VAR at different lung compliance. Initial data was gathered using a compliance of 60cc/cmH20. When set compliance was changed to 20, 30, 40, or 50cc/cmH20 the VAR repeatedly failed to trigger with initial set parameters (FR 30, PIP 20, RR 12). At that time we noted that the data we collected changed as the position of the VAR was manipulated. As a result we decided to evaluate positioning and the effects on the reliability and effectiveness of the VAR.
Conclusion: Our preliminary evaluation has demonstrated that use of the VAR presents some significant clinical concerns. Our primary concern is the inconsistent performance of the device under both test conditions. We suggest that at minimum all patients placed on the VAR be monitored continuously. The gravity dependent nature of the VAR suggests unreliable performance, especially when the device is positioned horizontally. If the manufacturer is able to overcome reliability issues then we suggest that lung compliance related limitations also be addressed. The VAR, with modifications, could be an alternative to other forms of ventilatory support if necessary. Further research is needed in order to evaluate the reliability and effectiveness of the VAR in low compliance scenarios and in use with PEEP valves. Protocol modifications which address positional orientation of the VAR are necessary.