Should oxygen inhalation be moderated? Will long-term oxygen inhalation cause poisoning?

For patients in the early stage of chronic obstructive pulmonary disease diagnosis, maintaining daily oxygen inhalation makes them feel happy. However, one view has always worried them. Will long-term inhalation of high-concentration oxygen, especially when they inhale oxygen for more than 10 hours a day like them, cause poisoning?

1. Will long-term inhalation of high-concentration oxygen cause poisoning?

We have all heard of drug poisoning and food poisoning. Have you heard of oxygen poisoning?

If a large amount of high-concentration oxygen is inhaled for a long time, for example, continuously inhaling 100% oxygen for 24 hours, it may cause oxygen poisoning, which will cause respiratory failure and severe hypoxia. However, this situation is difficult to occur in reality.

Oxygen poisoning only occurs when patients use ventilators to supply high-concentration oxygen for a long time or when the oxygen concentration in infant incubators is too high. Also, if hyperbaric oxygen therapy is improperly operated and the cabin pressure is too high and the oxygen inhalation time is too long when the patient inhales oxygen, oxygen poisoning may also occur. Normobaric oxygen inhalation is an important and commonly used rescue and treatment measure in hospitals. The commonly used nasal catheter oxygen supply method (as shown in the following figure, insert a catheter into the top of the nasal cavity for oxygen inhalation.) The patient inhales a mixture of oxygen and air, and the oxygen concentration is generally not more than 40% - 50% (oxygen partial pressure is lower than 60 kPa). Therefore, even if the patient inhales oxygen for a long time, oxygen poisoning will not occur.

2. Oxygen inhalation concentration and actual oxygen concentration reaching the lungs

To understand this problem, the key is to distinguish between the oxygen inhalation concentration and the oxygen concentration reaching the lungs.

There are always patients who ask if such a high oxygen concentration during oxygen inhalation will cause oxygen poisoning. This can be said to be a misunderstanding. The current oxygen therapy and oxygen health care equipment can be roughly divided into: health care oxygen generators with an oxygen concentration of 30% - 60%, molecular sieve medical oxygen generators with more than 90% oxygen concentration, and oxygen cylinders and portable oxygen bottles with even higher oxygen concentrations.

These devices basically rely on oxygen masks or nasal oxygen tubes for oxygen inhalation, which belongs to open oxygen inhalation. That is, when a person inhales a breath, the oxygen supply is insufficient, and some air (21% oxygen concentration) will be inhaled beside. The actual oxygen concentration reaching the lungs is the oxygen concentration after mixing with air, that is, the inhaled oxygen concentration. The formula for inhaled oxygen concentration (FiO2) = 21 + 4 * oxygen flow rate. As shown in the calculation in the following figure, even if oxygen with a concentration of 99% is inhaled, the oxygen concentration that actually reaches the lungs is only 33%, which is still far from the poisoning concentration of 70%.

So for long-term oxygen inhalation, if it is carried out in the form of a nasal oxygen tube under normal pressure, even if oxygen is inhaled continuously for more than ten hours a day, oxygen poisoning will not occur. It can be said that most patients' concerns about oxygen poisoning are unnecessary.

3. Long-term oxygen inhalation helps breathing smoothly.

In modern times, people's pace of life is getting faster and faster, the pressure is getting greater and greater, and mental and physical exertion is great. Some experts believe that at least 10% of people in cities are in a state of hypoxia. Daily oxygen inhalation can have the effects of reducing mental overdraft, relieving work pressure, and helping to relax.

For patients with chronic obstructive pulmonary disease, maintaining long-term oxygen inhalation is the fundamental treatment for chronic obstructive pulmonary disease. Maintaining long-term oxygen therapy can significantly solve the patient's breathing difficulties. Clinical data proves that maintaining oxygen inhalation for 15 hours a day and after 500 days, the patient's survival rate will be significantly improved and the quality of life will also be significantly improved.

So regarding home oxygen therapy, there is no need to worry about the problem of oxygen poisoning at all. On the contrary, for patients with chronic obstructive pulmonary disease, for their own health, they must adhere to long-term oxygen therapy and adopt scientific treatment methods. If there is any discomfort, do not make treatment decisions on your own. Go to the hospital as soon as possible to obtain professional advice.