2001 OPEN FORUM Abstracts
PERFORMANCEAND WEIGHT COMPARISON OF PORTABLE OXYGEN SYSTEMS
BlissPL, McCoy RW. Valley Inspired Products, Burnsville MN
Background:Recently, new systems for portable oxygen delivery have been introduced to allowlong term oxygen therapy (LTOT) patients greater mobility. Much of the improvementin weight and use time comes through the use of Demand Oxygen Delivery Systems(DODS). Each model of device delivers oxygen in a different manner, and settingsare not absolutely comparable to continuous flow oxygen (CFO) or to each other.We evaluated a measure of system portability, use time per unit weight, at comparableFIO2 levels, using a mechanical lung simulator. Three newer sytemswere compared with two more traditional, CFO delivery systems.
Methods: An apparatuswas constructed to simulate the nares, conducting airways and an alveolar chamberwith a machined ?nose?, flex tube (150 ml of deadspace) and a spontaneous breathingsimulator (Hans-Rudolph Series 1100). A simulated respiratory pattern (VT=515mL, f=20/min, I:E=1:2, decelerating flow wave) was generated. The oxygen deliverysetting of each device was adjusted to attain as close to 27% FIO2delivery to the alveolar chamber as possible, measured with an oxygen analyzer(Douglas Scientific). Oxygen pulses from the DODS were measured by a mass flowmeter(Model 4040 - TSI). The maximum FIO2 attainable with each device was measured(the highest deliver setting). Devices tested were Chad Therapeutics TotalO2301 system with M6 cylinder, Mallinckrodt Helios, Invacare Homefill II withM6 cylinder, Caire Stroller (continuous flow) and an aluminum ?E? cylinder withaluminum regulator. Systems were weighed when full with oxygen and includingany carrying bag or straps (cart for ?E? cylinder).
| Device||Setting ||FIO2 %||Device Weight lbs||Use Time hours ||Hours/lb||MAX FIO2 %|
|Stroller CFO|| 2 ||27.2|| 8.6 ||7.2|| .83||39.6 |
|E Cylinder CFO||2 || 27.2||15|| 5.3 ||.35 ||39.4 |
|TotalO2 ||3 ||27.9 ||5.7||4.4||.77 ||30.4|
|Helios ||3 || 26.8||4.0||6.4|| 1.6|| 28.0 |
|Homefill II|| 2.5|| 26.8|| 5.6|| 3.3|| .60|| 34.5 |
All DODS triggered theiroxygen delivery as anticipated. Higher DODS settings were required to attainsimilar FIO2 values to CFO. Not all devices had a setting to exactlymatch the FIO2 of CFO, which affects the use time and calculatedHours/lb..
Conclusion: Newoptions for LTOT patients can provide significantly lighter oxygen systems withthe comparable use times. The Helios system stands out as being much more weightefficient than other systems, but is limited in its maximumFIO2 delivery capability.