What Are the Side Effects of Oxygen Therapy?

Oxygen therapy refers to the improvement of blood oxygen reduction by inhaling oxygen to patients, and belongs to the category of inhalation therapy. This therapy can increase the partial pressure of arterial oxygen, improve the tissue hypoxia caused by the decrease of blood oxygen, and maintain the important organ functions such as brain, heart, and kidney. Work burden. It has better curative effect on hypoxia caused by decreased arterial blood oxygen partial pressure in respiratory diseases, and can only partially improve hypoxia condition caused by circulatory dysfunction or anemia.

Oxygen therapy

Oxygen therapy refers to the improvement of blood oxygen reduction by inhaling oxygen to patients, and belongs to the category of inhalation therapy. This therapy can increase arteries

The target of oxygen therapy is mainly for patients who lower the partial pressure of arterial oxygen, including hypoxemia due to various causes of ventilation, poor ventilation, and

The direct effect of oxygen therapy is to increase the partial pressure of arterial oxygen, improve tissue hypoxia caused by decreased blood oxygen, and maintain important organ functions such as brain, heart, and kidney; it can also reduce the increased heart rate and increased breathing during hypoxia. Heart and lung workload. The effect of oxygen supply varies depending on the cause of the decrease in blood oxygen. Respiratory disorders caused by decreased arterial oxygen pressure

The main targets of oxygen therapy are various patients who lower the arterial oxygen partial pressure, including hypoxia caused by various causes of ventilation, hypoventilation, and heart failure,

First, the most common patients with type 2 respiratory failure, such as COPD, are suitable for low-flow oxygen, and can be stimulated by hypoxia.

Basic illness

There are many causes of hypoxia. When performing oxygen therapy, first, actively treat the underlying lesions, otherwise the effect of oxygen therapy is not obvious or ineffective. Then, according to different basic diseases, choose different oxygen inhalation methods, concentrations and times, and the precautions are also different. If the central disease causes weak or stopped spontaneous breathing, mechanical ventilation combined with oxygen therapy should be performed; those with airway obstruction should immediately lift the airway obstruction, such as removing foreign bodies and laryngospasm, while giving a short period of high concentration oxygen therapy;

Overview

There are many methods of oxygen therapy, each with its own advantages and disadvantages. The basic principles that should be followed in the choice of oxygen therapy: from simple to complex, from non-invasive to invasive, timely monitoring and adjustment, in order to achieve the goal of improving hypoxia as soon as possible. Therefore, it is very important to monitor the effect of oxygen therapy during oxygen therapy. The monitoring of oxygen therapy mainly includes the following aspects:

FiO2 monitoring

FiO2 is the main factor determining the effect of oxygen therapy.

Overview

Oxygen is only a symptomatic treatment. At the same time, oxygen must be treated for the primary disease that causes blood oxygen decline. At the same time, the ventilation function is improved to facilitate the discharge of carbon dioxide. In order to ensure sufficient oxygen supply, attention must also be paid to the maintenance of cardiac function and anemia. Correct; make arterial blood when acute patient is given oxygen

The oxygen inhalation catheter must be placed in an effective area

This problem may seem simple, but it is often overlooked in the clinic, which seriously affects the effect of oxygen therapy and even delays the rescue time. In clinical rescue, it is not uncommon to leave an oxygen suction tube in the nasal cavity after tracheal intubation. How can this achieve the purpose of oxygen therapy? Because the situation of patients varies greatly during oxygen therapy, it should be particularly emphasized that care must be taken to ensure that patients can actually inhale oxygen into the lungs in order to achieve the effect of oxygen therapy. If the patient mainly breaths through the mouth, the oxygen suction tube should be placed in the mouth instead of the nasal cavity. At this time, if a nasal plug type oxygen suction tube is used, the nasal plug should be cut off to prevent it from being inhaled into the trachea by mistake. When intubating or incision of the trachea, the oxygen suction tube should be inserted into the cannula and fixed. When fixing the oxygen suction tube, care should be taken not to block the intubation port.

Misunderstanding of oxygen poisoning

Oxygen poisoning caused by oxygen therapy is often overstated in clinical practice. It is difficult to occur oxygen poisoning in the case of non-ventilator oxygen supply (ie, open oxygen supply), because FiO2 is difficult to exceed 0.6. Even when the ventilator gives oxygen, it should first consider ensuring that PaO2 is not lower than 50-60mmHg, and reduce FiO2 as much as possible under the premise of ensuring PaO2. If PaO2 cannot be guaranteed, the application of pure oxygen ventilation is also completely reasonable. Compared with maintaining life, oxygen poisoning can be ignored. Because severe hypoxia can quickly cause patients to die, it is very mechanical to limit FiO2 if anxiety about oxygen poisoning occurs. For example, during cardiopulmonary resuscitation, high-concentration oxygen or pure oxygen should be used to maintain ventilation as much as possible to improve and ensure tissue oxygen supply. Of course, after successful resuscitation, FiO2 should be adjusted to a safe range in time according to the situation.

Oxygen concentration estimation problem

When nasal catheters and ordinary masks inhale oxygen, they are affected by the patient's breathing depth frequency, etc. Even when the oxygen flow is the same, the inhaled oxygen concentration of different patients varies greatly. According to the formula Fi02 (%) = 21 × 4 × oxygen flow rate (L / min), the calculated Fi02 is only an approximate value. The actual Fi02 value is often lower than the calculated value, and the gap between the two increases with the increase of the flow rate. Big. At this time, no matter how to increase the oxygen supply flow rate, the actual Fi02 is difficult to increase to more than 50%. It can be seen that nasal catheters and ordinary masks will not cause oxygen poisoning when inhaling oxygen.

Monitor the effect of oxygen therapy and adjust the oxygen therapy plan in time

The effect of oxygen therapy is almost immediate, and the full effect can be achieved 20 minutes after the start of oxygen therapy. Therefore, it is very important to timely monitor the curative effect, and the oxygen therapy method and oxygen flow rate should be adjusted in time according to the curative effect to increase the PaO2 to an acceptable level (above 60mmHg) as soon as possible. If general oxygen therapy cannot effectively correct hypoxia in a short time, an artificial airway should be established as soon as possible for mechanical ventilation.

Watch for humidification of inhaled air

The humidity of the oxygen released from the compressed oxygen cylinder is usually less than 4%. Pay attention to the humidification of the gas. Low-flow oxygen supply generally uses a bubble humidifier, and high-flow oxygen supply should use a more effective humidifier to humidify the inhaled air.

Prevent cross infection

All oxygen supply devices, oxygen supply devices, including nasal catheters, nasal plugs, masks, humidifiers and other oxygen therapy supplies should be regularly disinfected and generally used by special persons. Strict disinfection is required when changing to other patients.

Emphasis on comprehensive comprehensive treatment

It should be recognized that oxygen therapy can only temporarily alleviate or improve the body's hypoxia, but cannot eliminate the root cause of hypoxia. Therefore, oxygen therapy is only a temporary treatment to prevent hypoxia, and cannot replace the cause of hypoxia. treatment. Therefore, while oxygen therapy is being used to correct hypoxemia and tissue hypoxia, active treatment of the underlying diseases that cause hypoxia should be carried out, such as controlling infections, eliminating airway spasms, and maintaining the patient's water and electrolyte balance.