Atmospheric pressure (standard atmospheric pressure): at the sea level of 450 degrees latitude of the earth, at 00, the pressure per square centimeter is 760 mmHg, which is called 1 standard atmospheric pressure, that is, atmospheric pressure.
Additional pressure (gauge pressure): The pressure exceeding the normal pressure is called additional pressure. Its size can be displayed by a pressure gauge, also known as gauge pressure. Under normal pressure, the gauge pressure shows "0". The pressure displayed by sphygmomanometer when measuring blood pressure is additional pressure.
Absolute pressure: the pressure per unit area is called absolute pressure, which is often used as therapeutic pressure in clinical hyperbaric oxygen therapy. Absolute pressure = "normal pressure+additional pressure (gauge pressure)", English abbreviation: commonly used ATA.
Local atmospheric pressure: the atmospheric pressure in different areas is not consistent, because the atmospheric pressure in different latitudes, temperatures and altitudes is different. For example, the atmospheric pressure in Lhasa is only about 65% of the standard atmospheric pressure. Every different atmospheric pressure on the earth is called local atmospheric pressure. Specifically, hyperbaric oxygen therapy should be based on local atmospheric pressure.
What is high pressure, what is hyperbaric oxygen and hyperbaric oxygen therapy?
High pressure: Any pressure higher than normal pressure (1 standard atmospheric pressure) is called high pressure.
Hyperbaric oxygen: Absorbing high-concentration oxygen in high-pressure environment is called hyperbaric oxygen.
Hyperbaric oxygen therapy: the method of treating many diseases with hyperbaric oxygen is called hyperbaric oxygen therapy.
What is the difference between atmospheric oxygen therapy and hyperbaric oxygen therapy?
Oxygen therapy includes atmospheric oxygen therapy and hyperbaric oxygen therapy. There are basically three differences between normal pressure oxygen inhalation and high pressure oxygen inhalation:
1, the required pressure equipment is different: normal pressure oxygen inhalation, patients use nasal catheter, mask, oxygen tent or artificial respirator under one atmospheric pressure; However, under high pressure, patients inhale pure oxygen in a special hyperbaric oxygen chamber in an environment above atmospheric pressure.
2. The concentration of inhaled oxygen is different: oxygen is inhaled under normal pressure, and the oxygen concentration is generally between 25-55%, while the oxygen concentration under hyperbaric oxygen is 85-99%.
3, the curative effect is completely different: high pressure oxygen inhalation can increase the blood oxygen content by several times or even dozens of times compared with normal pressure oxygen inhalation.
Hyperbaric oxygen can also significantly increase the content of physical dissolved oxygen in blood. The experiment shows that when the atmospheric pressure increases 1, the physical dissolved oxygen increases 14- 17 times. The famous paper "Life without Blood" published by the Dutch scholar Boerema confirmed that animals with almost no blood cells can still survive under hyperbaric oxygen, but under normal pressure, even if pure oxygen is inhaled, animals with red blood cells removed will soon die of hypoxia.
Under hyperbaric oxygen, the amount of oxygen in the body will also increase. Brain death may not occur after 65,438+07-26 minutes of cardiac arrest by inhaling oxygen at 3 atmospheres, but it will occur after 4-6 minutes of cardiac arrest by inhaling atmospheric air.
Other direct effects of hyperbaric oxygen: increasing the diffusion of oxygen in tissues and the effective diffusion distance of oxygen; It has inhibitory effect on bacteria; Compression and dissolution of bubbles; As well as the regulation of the whole body system, which can not be achieved by atmospheric oxygen.
Why do hyperbaric oxygen therapists do eustachian tube pressure regulation?
The human ear has an outer ear and an inner ear separated by a tympanic membrane. The outer ear communicates with the outside world through the external auditory canal, and the inner ear communicates with the outside world through the eustachian tube. Usually, the eustachian tube is closed. When pressurized, the external high pressure increases the external auditory canal pressure. If the inner ear pressure does not increase, the eardrum will sag inward, and people will feel stuffy, bloated and painful in their ears.
In order to prevent earache, everyone who enters the hyperbaric oxygen chamber should adjust the pressure of the eustachian tube, so that the eustachian tube can be opened, and the external high pressure can enter the inner ear through the eustachian tube, so that the pressure on both sides of the eardrum will be balanced, and our inner ear will not feel uncomfortable. Therefore, the person who enters the cabin should be a person with unobstructed eustachian tube (no acute or chronic sinusitis, upper respiratory tract infection and other diseases). In addition, before the patient enters the cabin, the patient should be taught to constantly adjust the pressure of the eustachian tube when raising and lowering the pressure.
How do I know if the eustachian tube is unobstructed?
Under normal pressure, hold both sides of the nose with both hands, close your mouth, and exhale forcefully to the nose (when the eustachian tube is unobstructed and the eardrum is intact). When exhaling, the eardrum bulges outward, indicating that the eustachian tube is unobstructed.
Eustachian tube pressure adjustment method
There are three ways to adjust the pressure: ① chew, ② swallow, ③ hold your nose and close your mouth to inflate. Generally speaking, the first two methods can be used. If the ear feels bloated, the third method can keep the pressure difference between inside and outside the periosteum balanced and the symptoms can disappear. If there is still no relief, the cabin medical staff need to adjust the speed of cabin pressure rise and fall.
Hyperbaric oxygen therapy is divided into several stages.
Hyperbaric oxygen therapy is generally divided into three stages.
(1) pressurization: the process of increasing from normal pressure to the required therapeutic pressure. Single pure oxygen cabin is directly pressurized with hyperbaric oxygen, and large, medium and small air cabins are pressurized with compressed air. Generally, the processing pressure is 2-2.5 atmospheres.
(2) Stabilization: When the pressure rises to the predetermined therapeutic pressure, immediately stop boosting to stabilize the pressure, which is also called high pressure retention. Patients wear masks to breathe and inhale pure oxygen during the stay time, while patients in single pure oxygen cabin inhale oxygen directly in the cabin. It usually takes 60-90 minutes under high pressure.
(3) Decompression: After hyperbaric oxygen treatment, exhaust at a certain speed, decompress to normal pressure, and leave the cabin. The time is about 20-30 minutes. Generally, the total treatment time is about 100- 120 minutes, and 10 days is a course of treatment, but the treatment time of different diseases is different.
Instructions before entering the cabin
1, patients treated with hyperbaric oxygen must be examined by hyperbaric oxygen specialists and treated with certificates. You should arrive on time, don't wait.
2. It is forbidden to carry kindling (lighters, matches, etc. ), inflammable, explosive and volatile goods (gasoline, alcohol, grease) and electrical equipment (mobile phones, business communications, electric toys, electric stoves, etc. ) enter the engine room, and it is forbidden to wear chemical fiber clothing to enter the engine room.
3. Do not bring watches, pens and other items unrelated to treatment into the cabin.
4. Gas-producing foods, such as bean products, onions and garlic, should not be eaten during treatment. No drinking.
5. Empty the urine before entering the cabin.
6, according to the requirements to replace the hospital special clothing and slippers.
7. When entering the engine room for treatment, you must obey the command of the medical staff. Please don't touch the engine room equipment to avoid accidents.
8, in the process of pressurization, under the guidance of medical staff to do a good job of middle ear pressure adjustment, earache and other discomfort to the medical staff in a timely manner.
9. When inhaling oxygen, please don't breathe excessively. If you have numbness or convulsions in your lips and limbs, stop oxygen inhalation immediately and report to the medical staff in time; If you feel unwell during the treatment, you should report to the medical staff at any time and wait for disposal.
10, please don't make any noise in the engine room, keep the engine room quiet and tidy, and don't spit or litter.
1 1, blood pressure, high intraocular pressure, cold, cough, high fever, diarrhea and acute infectious diseases are suspended. It is not suitable to enter the cabin during menstruation.
Why and when do vasodilators need to be used in hyperbaric oxygen therapy?
During hyperbaric oxygen therapy, the blood vessels of many organs or tissues, such as heart, brain, kidney, limbs, etc., can contract in different degrees, and the vascular resistance increases and the blood flow decreases. This is good for some diseases, but not good for some diseases. In order to avoid or alleviate this unfavorable factor, it is necessary to add vasodilators. Especially ophthalmic diseases and cardiovascular diseases, vasodilators should be added.
Vasodilators should generally be used 20-30 minutes before entering the cabin for treatment. Oral or intramuscular injection. Eye diseases can also be injected behind the ball.
What should patients pay attention to after hyperbaric oxygen therapy?
After decompression, if you feel unwell, you should contact your doctor in time. Pay attention to rest, drink hot drinks or take a hot bath after treatment to help nitrogen continue to be discharged. We should pay attention to strengthening nutrition and adopt a diet with high sugar, high protein, high vitamins, low fat and easy digestion.
Can hyperbaric oxygen therapy lead to oxygen poisoning?
Can hyperbaric oxygen therapy lead to the increase of oxygen free radicals and lead to oxygen poisoning?
What is oxygen poisoning? When oxygen with high concentration, high flow rate and high partial pressure is inhaled for more than a certain period of time, when oxygen free radicals are produced more than eliminated, excessive oxygen free radicals may cause functional or organic injuries such as reperfusion injury and apoptosis. This kind of injury is usually called oxygen poisoning.
However, it goes without saying that oxygen free radicals are also a double-edged sword. A proper amount of oxygen free radicals in the body is beneficial to the body. Besides sterilization, it can also promote the synthesis of prostaglandin, thyroxine, prothrombin, collagen and ribonucleoside. Under normal circumstances, the generation and elimination of oxygen free radicals in the body are in dynamic balance. Especially, the production of free radical scavenging enzymes under hyperbaric oxygen is much higher than that under atmospheric oxygen. Experiments show that under some pathological conditions, hyperbaric oxygen can also reduce the production of oxygen free radicals.
How much oxygen can cause oxygen poisoning?
Usually, oxygen inhalation through nasal catheter (the inhaled oxygen concentration is less than 40%) in atmospheric oxygen therapy will not cause oxygen poisoning, but oxygen poisoning may occur after continuous oxygen inhalation 15 days; Oxygen poisoning can occur when inhaling high concentration oxygen (> 60%) at normal pressure for about 8- 12 hours.
When the pressure of hyperbaric oxygen therapy is 2 atmospheres, oxygen poisoning can occur after continuous inhalation for about 2-4 hours. At 3 atmospheres, continuous inhalation of 1-2 hours can cause oxygen poisoning. At present, hyperbaric oxygen therapy mostly adopts intermittent oxygen inhalation, and the pressure is generally 2 atmospheres. After inhaling for 30 minutes, rest for 5- 10 minutes, inhale for another 30 minutes, * * * inhale 1 hour. It can be seen that the pressure and time of oxygen inhalation in hyperbaric oxygen therapy are within the safe range. Therefore, the answer is yes: normal hyperbaric oxygen therapy will not cause oxygen poisoning.
Is hyperbaric oxygen a dispensable adjuvant therapy?
In the process of fighting diseases, the measures taken by people can be divided into: 1, gas therapy (currently oxygen therapy), 2, liquid therapy (various infusion treatments), and 3, solid therapy (various drug treatments and surgical treatments).
Judging from the development history of medicine, the history of treating diseases with drugs is the longest, so consolidating the foundation is the foundation. But with the development of science, one day people will find that the mobilization of qi will be the basis of maintaining life. Because the human body's ability to store gas is the most limited (about 6 minutes), followed by liquid (about 6 days) and solid (about 6 weeks). According to the human body's reserve of three-state substances, hyperbaric oxygen therapy should be the basis of other treatment methods.
Therefore, hyperbaric oxygen is by no means a dispensable adjuvant therapy. To be exact, from the current application breadth, development history and uniqueness, hyperbaric oxygen is no less than drug treatment and surgical treatment. As a means of treatment, it plays an important role in modern medical practice and has developed into a part of modern medicine. Its curative effect is recognized by the international medical community. It has a unique curative effect on treating systemic or ischemic and hypoxic diseases. It is unmatched by other treatments.
Timing of hyperbaric oxygen therapy
Due to the lack of understanding of the efficacy of hyperbaric oxygen, some indications have not been treated in time, resulting in lifelong regret.
For example, brain edema and intracranial pressure will increase in the early stage of cerebral infarction and brain trauma. The repair of brain tissue starts from 5-6 days after illness and lasts for 2-3 weeks. Therefore, the treatment can be started within 1 week, and the effective rate can reach more than 96% within 1 month. It is now advocated that patients with cerebral infarction should be treated in the cabin within 2-6 hours. 5-7 days after brain surgery, the condition can be treated smoothly.
Facial neuritis and polyneuritis: once diagnosed, the treatment time should be as early as possible.
Acute spinal cord injury: Generally speaking, it is better to start treatment within 4 hours after injury.
Sudden deafness: treatment within 2 weeks can improve the cure rate.
Blasting deafness: the treatment effect is the best within 3 days.
Retinal artery embolization: the treatment effect is good within 10 hour after onset; Poor prognosis after more than 24 hours; Treatment is ineffective after more than 5 days.
Fracture: Treatment was started within 10 day, and it was done for more than 20 times continuously. The primary healing rate reached 100%.
The timing of hyperbaric oxygen therapy should be-the sooner the conditions permit, the better.