We will look at the following factors:
- Medical oxygen flow rate.
- Inhaled oxygen concentration range.
- Main applicable population.
- Compatibility with noninvasive ventilator.
- Ability to bear workload.
- Domestic market conditions.
Medical oxygen flow rate.
The medical grade oxygen flow range of the 1.3-liter and 5-liter machines is different for a 3-liter oxygen generator, when the oxygen flow rate is 1-3 L, the “oxygen concentration” reaches 90% – 96%, that is, the oxygen flow rate of the 3-liter oxygen generator per minute can be selected by the user as 1 liter / min, 2 L / min and 3 L / min, which can provide oxygen with oxygen concentration of 90% – 96%. It should be noted that some 3-liter oxygen generators can be adjusted to 4-liter and 5-liter gas, but in this case, the oxygen output concentration of the machine is no longer 90% – 96%. The increase in oxygen concentration of 5 liters will be reduced to about 70%. When selecting from 1-5 l oxygen flow rate, the “oxygen concentration” reaches 90% to 96%, that is, the 5-liter oxygen generator not only includes: when the oxygen flow rate is 1, 2 and 3 L per minute, the oxygen concentration is 90% to 96%; at the same time, when 4 L / min and 5 L / min are selected, it can provide oxygen therapy with oxygen concentration of 90% to 96%.
Inhaled oxygen concentration range.
The range of FIO2 values of “inhaled oxygen concentration” for 3-liter and 5-liter engines is different.
What is the inhaled oxygen concentration FiO2?
FiO2 is the abbreviation of inspired O2 score. Chinese is interpreted as the fraction of oxygen concentration in the inhaled gas, known as the inhaled oxygen concentration. It is usually used to indicate the percentage of oxygen in the alveoli involved in gas exchange.
Because: the range of medical oxygen flow of 3-liter oxygen generator and 5-liter oxygen generator is different, so when you use the most common nasal oxygen tube (also known as: nasal catheter, nasal tube), this equipment will inhale oxygen. Due to the oxygen flow rate, the concentration of inhaled oxygen FiO2 is different.
Standard nasal oxygen tube.
“Standard nasal oxygen tube” is a low flow oxygen inhalation device. Usually used for oxygen therapy, up to 6 L / min. It belongs to open oxygen inhalation. The actual oxygen concentration to the lung is: the oxygen concentration after the oxygen from the oxygen generator is mixed with the air.
Methods of nasal oxygen tube inhalation.
If the most common nasal oxygen tube is used for oxygen inhalation, the estimated value of FIO2 is obtained according to the oxygen flow rate and oxygen concentration.
Estimated value of FIO2 = 21% + 4 × oxygen flow rate per minute (L) × oxygen concentration of oxygen generator (%)
From the above formula.
we can get the corresponding data of estimated oxygen flow rate and FiO2 (inhaled oxygen concentration): oxygen flow rate (L / min) oxygen concentration (%) estimated FiO2 (with nasal oxygen tube)
- 1 liters/min 90% ~ 96% 24.6% ~ 24.84%
- 2 liters/min 90% ~ 96% 28.2% ~ 28.68%
- 3 liters/min 90% ~ 96% 31.8% ~ 32.52%
Similarly, we can also get the corresponding data of the 5-liter home oxygen generator, the oxygen flow rate and FiO2 (inhaled oxygen concentration) estimated value:
Oxygen flow rate
Oxygen flow rate (l/min) Oxygen concentration (%) FiO2 estimated value (with nasal oxygen tube)
- 1 liters/min 90% ~ 96% 24.6% ~ 24.84%
- 2 liters/min 90% ~ 96% 28.2% ~ 28.68%
- 3 liters/min 90% ~ 96% 31.8% ~ 32.52%
- 4 liters/min 90% ~ 96% 35.4% ~ 36.36%
- 5 liters/min 90% ~ 96% 39.0% ~ 40.20%
1. The applicable population of 3 liter oxygen generator and 5 liter oxygen concentrator is different
The 1 liter and 2 liter oxygen generators are mostly used for health-care oxygen inhalation for people with mild hypoxia, such as pregnant women and white-collar workers with mild hypoxia.
The 3-liter oxygen generator is mostly used for people with mild to moderate respiratory diseases, cardiovascular and cerebrovascular diseases, and three highs.
The 5-liter oxygen generator is mainly used for: severely ill patients, people who need to use ventilator, and people who need long-term oxygen inhalation every day: COPD, lung fiber, lung resection, lung cancer, pneumoconiosis, silicosis and other people.
2. Three oxygen machine and five oxygen machine are suitable for different people
The 1-liter and 2-liter oxygen generators are mainly used for healthy oxygen inhalation in people with mild hypoxia, such as pregnant women and white-collar workers with mild hypoxia.
The 3-liter oxygen generator is mainly used for: mild to moderate respiratory diseases, cardiovascular and cerebrovascular diseases and three large populations.
The 5-liter oxygen generator is mainly used for severe patients, those who need to use ventilator and those who need to inhale oxygen for a long time every day: COPD, lung fiber, pneumonectomy, lung cancer, pneumoconiosis, silicosis, etc.
Helicopter and helicopter compatible “noninvasive home ventilator” will be different.
Domestic noninvasive ventilator is different from the ventilator used in hospital. The oxygen source is usually provided by an additional oxygen generator because the mask has a “storage effect” of carbon dioxide and the pressure in the mask is relatively high, usually less than 5 L / min of oxygen flow rate and oxygen can not enter the mask well. As a result, it naturally cannot enter the respiratory tract and lungs, nor can it exhale carbon dioxide from the mask.
3. The compatibility of 3-liter machine and 5-liter machine is different from that of “household noninvasive ventilator”
The noninvasive ventilator used at home is different from that used in hospital. The oxygen source is usually provided by an additional oxygen generator, because the mask has a “storage effect” of carbon dioxide, and the pressure in the mask is relatively large, usually less than 5 L / at a small oxygen flow rate, oxygen cannot enter the mask well, so it will not enter the respiratory tract and lungs, and the exhaled carbon dioxide cannot be discharged from the mask.
In addition, due to the large airflow in the mask, the incoming oxygen will be seriously diluted. Therefore, if the low flow oxygen output of the 3-liter oxygen generator is connected to the noninvasive home ventilator, the oxygen demand of the patient can not be met, which will affect the treatment effect of the patient.
Therefore, when patients need to connect a home noninvasive ventilator to an oxygen generator, doctors usually recommend that they need at least a 5-liter domestic oxygen generator or a large flow oxygen generator.
4. 3L and 5L machines have different molecular sieve consumption and compressor performance, and they can bear different working loads.
Generally speaking, the number of molecular sieves installed in 5-liter oxygen generator is more than that in 3-liter oxygen generator. At the same time, its power components are also the main cost. The air compressor in the oxygen generator can work. More load. It is more suitable for people who need long-term oxygen therapy every day. For example, for people with COPD, they should use a 5-liter oxygen generator instead of a 3-liter oxygen generator.
In the process of oxygen inhalation, COPD patients should take low flow rate: 1.5 to 2.5 liters of oxygen per minute for oxygen treatment, which makes some people think that only 3-liter oxygen generator is enough. Oxygen inhalation in terms of time, for COPD patients, the amount of oxygen treatment required per day is relatively long. They are often advised to have oxygen therapy for at least 15 hours a day. If allowed, 24 oxygen inhalation is preferred.
3-liter oxygen generator, only 1.5-2.5 liters per minute. The air compressor on the 3-liter machine has undertaken a certain amount of work, and then needs 15 hours or 24 hours of long-term work, which makes the service life of the compressor sharply decline, and it is easy to cause machine failure.
For 5-liter oxygen generator, many companies design the 5-liter oxygen generator as a 24-hour operation mechanism, with larger compressor displacement and stronger performance. When selecting 1.5-2.5-liter, the 5-liter compressor has greater displacement and more surplus. Although the displacement of the 5-liter compressor has been relieved in long-term operation, it can also meet the minimum requirements of the system and has a longer service life. For COPD patients, this oxygen inhalation method is more stable and appropriate. This is an important reason why many professional doctors advise them to use a 5-liter oxygen generator.
In particular, users who have been on the phone for 15 hours or 24 hours usually take oxygen during the night break. Among the 5-liter oxygen generators, there are many high-end silent and high-quality oxygen generators. To better meet their oxygen needs.
