2007 OPEN FORUM Abstracts
EVALUATION OF OPERATING TIMES OF THE LTV-1000 EXTERNAL LITHIUM ION BATTERY
D. Rodriquez 1, S. L. Barnes1, 2, J. A. Johannigman2, 1, R. D. Branson2, 1
Background: Portable ventilators commonly include an internal battery for operation from 1-2 hours. For longer duration transports, an external battery is used. The LTV-1000 includes an external lithium-ion battery (LIB) for extended transport reported to provide power for 4 hours (240 mins) at nominal settings. We evaluated the battery life of the (LIB) under conditions of changing breath type, PEEP, and FIO2.
Methods: An LTV-1000 was connected to a Michigan Instruments Test Lung (TL) via a disposable, proprietary circuit. Compliance of the TL was constant at 0.02L/cm H2O and resistance was 5.0 cm H2O/L/s. Prior to each study, the battery was operated until empty and charged over night for a minimum of 12 hours. The ventilator was then operated from the LIB using the following ventilator conditions a minimum of two times. Respiratory frequency was 10 b/min and inspiratory time was 1.5 seconds in all cases. Eight tests were performed with the following settings: Test 1 Volume control (VC), VT 750 mL, PEEP 0, FIO2 0.21, Test 2 VC, VT 750 mL, PEEP 0, FIO2 -1.0, Test 3 VC, VT 750 mL, PEEP 20, FIO2-0.21,Test 4 VC, VT 750 mL, PEEP 20, FIO2 1.0, Test 5 Pressure Control (PC) VT 750 mL, PEEP 0, FIO2 0.21, Test 6 PC VT 750 mL, PEEP 0, FIO2 1.0, Test 7 PC VT 750 mL, PEEP 20, FIO2 0.21, Test 8 PC VT 750 mL, PEEP 20, FIO2 1.0.
Results: Shorter durations of operation were seen with the use of PC vs. VC, increasing FIO2, and increasing PEEP. The Table below depicts the data.
Conclusions: PC is associated with shorter battery life (~ 50% less) compared to VC regardless of PEEP or FIO2. Increasing FIO2 reduced battery life (~25%), and increasing PEEP reduced battery life (~27%) regardless of breath type. The combination of PC, elevated FIO2, and PEEP resulted in the shortest duration of operation. Clinicians must be aware of the effects of ventilator settings on battery duration for adequate transport planning.
The views expressed here are those of the authors and do not reflect official policy of the United States Air Force, Department of Defense, or the US Government.
|1||300 ± 11.6||p< 0.001 vs. Test 2, 3, 4,and 5|
|2||247 ± 2.1||p < 0.001 vs. Test 3, 4, and 6|
|3||211 ± 3.5||p < 0.001 vs. Test 4, 7, and 8|
|4||188 ± 6.3||p < 0.001 vs. Test 8|
|5||142 ± 3.5||p < 0.001 vs. Test 6, 7, and 8|
|6||126 ± 2.8||p < 0.001 vs. Test 8, p < 0.01 vs. Test 7|
|7||118 ± 0.7||p < 0.001 vs. Test 8|
|8||104 ± 4.9||p < 0.001 vs. all other tests|