Combining helium and oxygen reduces airflow limitations, lung dynamic hyperinflation, and sensation of shortness of breath, reported researchers in the Journal of Applied Physiology (November 2004). The study showed that, while breathing a low-density mixture of 79% helium and 21% oxygen, the length of time that 12 patients with chronic obstructive pulmonary disease (COPD) could do real exercise was 9 minutes, compared with 4.2 minutes for 12 patients breathing regular air (79% nitrogen and 21% oxygen).
The researchers said that the more than doubling of the time the participants with COPD could exercise "was associated with a significant reduction in lung dynamic hyperinflation at isotime (when the patients stopped exercising during regular air breathing), as reflected by the increase in inspiratory capacity to 1.97 L from 1.77 L and a decrease in dyspnea" scoring to 6 from 8.
In Seniors: Consider CMV Serostatus
When Recommending Flu Vaccine
Older people who have cytomegalovirus seem to have less robust responses to the trivalent influenza vaccine than those who do not have CMV.
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