Are you short of breath after a little activity? Check this indicator! If it is below 60, your life will be in danger!

People are breathing all the time, just like the heart is beating all the time. Breathing is a necessary condition for maintaining life. When breathing stops, life can no longer continue.

Breathing is the process of inhaling oxygen and expelling carbon dioxide. When there is a problem with the respiratory function, gas exchange cannot be carried out effectively, resulting in a decrease in the oxygen content in the blood, with or without carbon dioxide retention, which causes various symptoms. When it reaches a certain level, it will be defined as respiratory failure .

01

What is respiratory failure?

In general, the oxygen content in the blood is measured by the blood oxygen partial pressure index. Blood oxygen partial pressure, that is, the pressure generated by oxygen molecules physically dissolved in the blood, is normally between 80 and 100 mmHg for adults. The blood oxygen partial pressure value decreases with age, but the lowest value is probably above 80 mmHg.

If the blood oxygen partial pressure is lower than 60 mmHg under standard atmospheric pressure, it is medically defined as respiratory failure .

Copyright image, no permission to reprint

Respiratory failure is divided into type I and type II. Type I respiratory failure means that oxygen intake is affected, but carbon dioxide can still be discharged normally; type II respiratory failure means both hypoxia and carbon dioxide retention. In other words:

Type I respiratory failure: oxygen partial pressure is less than 60 mmHg, carbon dioxide partial pressure is normal;

Type II respiratory failure: oxygen partial pressure is less than 60 mmHg and carbon dioxide partial pressure is greater than 50 mmHg.

02

Patients with respiratory failure

What will the symptoms be?

The most important manifestation of respiratory failure is dyspnea , which can be manifested by shortness of breath after a little activity, breathlessness when talking, and labored breathing when sitting still. The more severe the condition, the more obvious the corresponding symptoms.

Respiratory failure can be acute or chronic. Patients with acute respiratory failure experience dyspnea more quickly, and their tolerance is poor. They will soon become hypoxic and must be treated as soon as possible. Patients with chronic respiratory failure develop dyspnea gradually, and although there is a tolerance process, breathing is still very laborious.

Patients with respiratory diseases are more likely to suffer from respiratory failure. For example, a sudden asthma attack may cause respiratory failure for patients with bronchial asthma. Also, patients with chronic obstructive pulmonary disease may suffer from respiratory failure if they do not pay attention to controlling their condition and catch a cold or pneumonia.

Copyright image, no permission to reprint

After respiratory failure occurs, the oxygen content in the blood is low, which first affects the nervous system, manifesting as slow reaction. In case of acute hypoxia, consciousness may be suppressed, and in severe cases it may cause coma.

When the carbon dioxide concentration starts to rise slightly, carbon dioxide accumulates in the blood and forms carbonic acid, leading to hypercapnia. At first, it can make people excited, just like being drunk, but when it rises severely, people will fall into a coma.

It also affects other systems, such as heart contraction, liver, gastrointestinal tract, etc., so the effects of hypoxia and hypercapnia are systemic.

03

How is respiratory failure treated?

Because patients with chronic respiratory failure have low oxygen levels in their blood, they need constant oxygen supplementation and usually require oxygen therapy.

Oxygen therapy can alleviate the patient's symptoms of respiratory failure, improve the patient's quality of life, enhance the patient's mobility, expand the patient's range of activities, and prolong the patient's life.

Generally speaking, for patients with chronic respiratory failure, oxygen therapy at home is usually recommended to be performed through nasal cannula oxygen inhalation .

Copyright image, no permission to reprint

If the concentration of oxygen inhaled through the nasal cannula cannot meet the needs and a higher concentration of oxygen is needed, you can choose to inhale oxygen through a mask. The mask is actually buckled directly on the mouth and nose, so the concentration of oxygen inhaled in this way will be much higher than the concentration of oxygen inhaled through a nasal cannula.

When oxygen inhalation through a mask cannot meet the patient's needs, oxygen is needed through a breathing device, such as a non-invasive ventilator, which injects gas into the trachea through positive pressure.

Copyright image, no permission to reprint

In addition, patients with chronic respiratory failure should also pay attention to controlling the primary disease, maintaining adequate nutrition, and avoiding bad habits such as smoking .

To treat acute respiratory failure, patients must first be provided with oxygen , and oxygen inhalation is also the most important means of treatment and rescue. The choice of non-invasive or invasive ventilator is based on the degree of respiratory failure and consciousness of the patient.

Invasive ventilators are somewhat traumatic to patients and require tracheal intubation, and then high-pressure gas is injected directly into the airway through the machine.

Copyright image, no permission to reprint

When the patient can get enough oxygen to sustain life, the next step is to treat the disease that causes the patient's respiratory failure, such as bronchial asthma, chronic obstructive pulmonary disease, etc. At the same time, through drug treatment, assisted ventilator and other methods, try to keep the patient's airway open.

When the acute or critical stage of the primary disease is relieved, respiratory failure will also be relieved in most cases. For example, during the acute exacerbation of COPD, the lung infection worsens. After the acute period is over, the patient may be able to return to the state before the acute exacerbation after using a non-invasive ventilator and drug treatment. The patient can leave the ventilator and slowly recover through oxygen therapy and other treatments.

Even with treatment, the respiratory failure condition cannot be alleviated for some diseases. For example, in pulmonary fibrosis, the lung tissue is completely destroyed. There is no good lung tissue left, and there is no way to complete the exchange of external oxygen and carbon dioxide in the blood. Even with the use of a ventilator, it is difficult to improve this condition.

Therefore, whether respiratory failure can be controlled depends on the primary disease that causes respiratory failure and how well it is controlled.

It also tells us that it is important to prevent respiratory failure. We cannot wait until respiratory failure occurs before treating the primary disease. Actively treating and controlling the primary disease is the fundamental way to prevent respiratory failure.

Produced by: Chinese Medical Association

Author: Ma Yingmin, Chief Physician, Beijing You'an Hospital, Capital Medical University, Member of the Critical Care Medicine Group, Ninth Committee of the Chinese Society of Respiratory Medicine

Reviewer: He Quanying, Chief Physician, Peking University People's Hospital

The cover image and the images in this article are from the copyright library

Reproduction of image content is not authorized