The Science Journal of the American Association for Respiratory Care

2009 OPEN FORUM Abstracts


Dario Rodriquez1,Thomas Blakeman2, Richard Branson2; 1CSTARS (Center for Sustainment ofTrauma and Readiness Skills), University Hospital, Cincinnat, OH; 2Surgery, University of Cincinnati, Cincinnati, OH

Background: The space program and military air transport represent challenging environments for medical care. Size and weight of compressed gas and the possible added risk of fire, compound the arduous task of patient transport. A proposed solution is to use a portable oxygen concentrator (POC) for O2 administration. An assessment of the Sequal Eclipse II and Integra POCs was conducted evaluating the fraction of inspired oxygen (FIO2) and flow/volume across the range of capabilities. Methods: Evaluations were conducted in a hypobaric chamber. The POCs were tested at sea level and simulated altitudes of 8000 ft, 16000 ft, 24000 ft, and 32000 ft. Each POC was attached to an analyzer measuring FIO2, flow, volume (pulse dose), temperature and power consumption. Measurements were made across the range of POC capabilities at each altitude. The Eclipse II was evaluated in both continuous and pulse dose modes. Measurements of chamber barometric pressure (PB), temperature, and relative humidity were recorded at each altitude. A trial of battery duration of the Eclipse II at sea level and altitude of 8000 ft was performed. Data shown are the average of three measurements produced with each condition on both POCs. Results: The delivered FIO2 was highest at sea level. FIO2 diminished as PB decreased. The Eclipse II failed to operate above 22000 ft. Power consumption was reduced at higher altitudes. At the highest flow settings, power consumption diminished by 30% during continuous flow and 31% during pulse dose in the Eclipse II and 19% in the Integra comparing sea level to 8,000ft. Battery duration on the Eclipse II at 8000 ft and 3 lpm was 1 hr 48 mins compared to 1 hr and 22 mins at sea level. Conclusion: The relatively high FIO2 delivered by the POCs makes this method of O2 delivery a viable alternative to compressed O2 in select situations. POCs cannot deliver an FIO2 of 1.0, necessitating complementary compressed gas for these scenarios. At operational PB, POC function remains equivalent to operation at sea level. The PIO2 available to the patient however, remains constrained by lower PB as altitude increases. At sea level (PB of 750 mmHg) an FIO2 of 0.90 produces an alveolar O2 of 582 mmHg, at 8,000 ft (PB of 564 mmHg) an FIO2 of 0.90 produces an alveolar O2 of 415 mm Hg whereas, at an altitude of 32,000 ft (PB of 206 mmHg) an FIO2 of 0.90 produces an alveolar O2 of 93 mmHg. Sponsored Research - NSBRI SMS 0005