The purpose of this study was to assess the metabolic costs of different supplemental oxygen delivery modalities (portable oxygen containers, POCs).
In this randomized, cross over study, 19 subjects aged 25.26 ± 8.16 yr performed a series of four six-minute walk tests (6MWT.) These consisted of three experimental 6MWTs, and one baseline. The experimental conditions included: 1. POC on right shoulder, 2. roller assist device, and 3. backpack. Measurements taken included: peak oxygen consumption (VO2peak) oxyhemoglobin saturation (SpO2) heart rate, 6MWT distances, and relative perceived exertion (RPE.).
Data was analyzed using SPSS version 15. One-way repeated measures ANOVAs were used to compare the average SpO2, average heart rate, total distance, and VO2peak. No significant effect was found for oxygen saturation (p = 0.62,) HR (p = 0.99,) RPE (p = 0.35,) or VO2peak (p = 0.96.) between the three experimental conditions. A significant effect was found for total distance (p < 0.001.) Follow-up protected t tests revealed that the distance decreased between baseline (2071.79 ± 303.77) and the shoulder condition (1944.21 ± 282.19)(p < 0.003), the backpack condition (1985.53 ± 288.78) (p = 0.003), and the roller condition (1905.84 ± 275.87) (p < 0.001). The difference in distance walked between the backpack condition (1985.53 ± 288.78) and the roller condition (1905.84 ± 275.87) was also significant (p = 0.036.).
In a healthy population performing standardized 6MWTs, there are no differences in metabolic expenditures associated with the use of a POC. Total distance of the 6MWT was reduced by POC use. There were differences in 6MWT distance associated with the type of POC used.
While there is no difference in metabolic demand or perceived exertion associated with POC use during a 6MWT, there are differences in distance walked. Further research on the effects of POC use in the COPD population with chronic respiratory failure is warranted.
Matthew Krauza, No Financial Disclosure Information; No Product/Research Disclosure Information