This is part one of a three-part article. Click here for part 2: “Using Your Own Oximeter.” Click here for part 3: “Breathing Techniques.” To read the entire article on PERF’s main website, click here.
By Mary Burns, RN, BS
PERF Executive Vice President
Summer vacations are upon us and some of you have expressed concerns about going to higher altitudes, either by flying, or by driving up to the mountains. You may remember that as you ascend in altitude you take in less oxygen with each breath, because the air pressure decreases, making the air “thinner” than at sea level.. That means that your arterial blood oxygen, and your oxygen saturation, also decrease. Pulmonary patients, who already have low blood oxygen at sea level, may have a problem at altitudes as low as 3,000 feet where barometric pressure is 10% lower than at sea level. (Remember that planes are pressurized at about 5,000 to 8,000 feet and occasionally even higher!)
Before we get started with a discussion of oxygen needs, it is important to point out that many people with lung disease, even fairly severe disease, have been evaluated and found to have no significant problem with oxygen levels in their blood. If this is true for you, great! If not, read on.
How can the doctor tell if you need to increase the liter flow of your oxygen, or if you need to be put on supplemental oxygen when you fly across the country, or drive up to the mountains? Needs vary with the individual and can be hard to estimate.
Your physician might know from experience what your oxygen needs may be at higher altitudes. A walking test to see if you desaturate, (if your oxygen level decreases) and how much you desaturate when walking, can help with this estimate of your oxygen needs at various altitudes. For some individuals, when there is concern about the safety of going on a long trip, a HAST (High Altitude Simulation Test) might be ordered. This provides accurate information on what your oxygen saturation will be at about 8,000 feet and is easily done in a pulmonary function lab, where you will be tested while you breathe air containing 15% oxygen.
If you do need oxygen when flying, make sure you contact your airline company well in advance! Make sure you understand what their rules are for oxygen use, or taking along your equipment! If they want an oxygen prescription from your doctor, bring at least one duplicate!
Next week: Using Your Own Oximeter To Measure Oxygen Saturation