oxygen,
Element name comes from the Greek, meaning "acid-formers." 1774 British scientists Priest with a lens to focus sunlight on mercuric oxide, discovered a strongly help the combustion gases. Lavoisier studied this gas, and the correct interpretation of the role of this gas in the combustion. Oxygen is the most abundant in the earth's crust, the most widely distributed elements in the crust of the content of 48.6%. 23% of elemental oxygen in the atmosphere. Oxygen has three stable isotopes: oxygen-16, oxygen-17 and oxygen-18, the highest oxygen content of 16.
Basic interpretation
Non-metallic gas chemical element, atomic number 8, the symbol O.
Element Information
Basic Information
[Name] oxy
[8] Order Number
[Symbol] O
[Atomic] 15.9994
[Simple cubic lattice crystal structure] [sound propagation speed] 330m / s
[14.0] atomic volume (cc / mol)
[8] the number of protons
Number of neutrons [8]
[8] the number of extranuclear
Relative atomic mass [16]
[Peripheral] 2s² 2p4 electron shell arrangement
[Shells] K-L
[2-6] arrangement extranuclear
[In the sun] element content 9000ppm
[Content] crust 474000 (ppm)
[Valence] was usually the -2
[Elemental] O2, O3, O4, O5
Oxidation states:
Main O-2
Other O-1, O0, O + 1, O + 2
Bond energy: (kJ / mol)
146 O-O
498 O = O
200 O-N
360 O-C
743 O = C
Ionization energy (kJ / mol)
M - M + 1313.9
M + - M2 + 3388.2
M2 + - M3 + 5300.3
M3 + - M4 + 7469.1
M4 + - M5 + 10989.3
M5 + - M6 + 13326.2
M6 + - M7 + 71333.3
M7 + - M8 + 84076.3
Cell parameters:
a = 540.3 pm
= 342.9 pm
c = 508.6 pm
α = 90 °
β = 132.530 °
γ = 90 °
Thermal conductivity: W / (m · K)
26.58
Element types: non-metallic
Origin
Oxygen by the English chemist Joseph Priestley and Scheele Sweden pharmacists and chemists in 1774 were found. But Priest actually support phlogiston theory. Another theory is that oxygen first by Chinese troops and was first discovered. In 1777, French chemist Lavoisier proposed oxidative combustion theory, pointing out substances can only be burned in an oxygen-containing atmosphere to increase the weight of the combustion air in the loss of oxygen equal overturned the whole of phlogiston, and the formal establishment of conservation of mass. Strictly speaking, oxygen is found Swedish chemist Scheler, and determine the chemical properties of oxygen for the French chemist Lavoisier.
Name
Oxygen (Oxygen, old translated Yang) is a chemical element whose atomic number is 8, the relative atomic mass of 16.00. By the symbol "O" indicates. In the periodic table, oxygen is a chalcogen, it is also a high reactivity of the second cycle of non-metallic elements, easily with almost all other elements to form compounds (primarily oxides). Under standard conditions, two oxygen atoms combine to form oxygen, it is a colorless, odorless and tasteless diatomic gases, chemical formula O2. If calculated according to the quality of the oxygen content in the universe after hydrogen and helium in the Earth's crust, oxygen is the most abundant element. Oxygen accounts for only 89% of the mass of water, also accounted for 20.9% of the volume of air.
All major compound contains oxygen constituting the organism, including proteins, carbohydrates and fats. Constitute animal shells, teeth and bones are mainly inorganic compounds containing oxygen. By the cyanobacteria, algae and plants through photosynthesis to produce oxygen chemical formula O2, almost all of the complex cellular respiration organisms require the use of oxygen. Animals, except a very few, are unable to survive for life out of oxygen. For anaerobic organisms, oxygen is toxic. Such was the main biological organism on the early Earth, until 2.5 billion years ago, O2 began to accumulate in the atmosphere. Another allotrope of oxygen is ozone. The formation of ozone at high altitudes can isolate UV radiation from the sun. But the near-surface ozone is a form of pollution, mainly in the ozone photochemical smog.
Oxygen is by Joseph Priestley and Carl Wilhelm Scheele found independently. Although early detection 卡尔比约瑟夫 year, but due to Joseph first published, many people still believe that Joseph first discovered. Oxygen English name is "Oxygen", named by the Lavoisier in 1777, Calatrava ene oxygen use test carried out in terms of combustion and corrosion defeated the then popular phlogiston. In industry, the oxygen is prepared by fractional distillation of liquid air, while using a molecular sieve to remove carbon dioxide and nitrogen. Oxygen can also be prepared by other means such as water electrolysis. The use of oxygen includes steel smelting, plastics and textiles as well as a rocket propellant manufacturing and subjected to oxygen therapy, also used in aircraft, submarines, spacecraft and dive sustain life. Old Yang translated oxygen (Oxygen) in Greek means "Sanso," the name is played by the French chemist Lavoisier, because Lavoisier mistakenly believed that all acids contain this new gas. Now Japanese name in oxygen is still "Sanso." The Taiwanese affected Taiwan under Japanese rule, but also to "Sanso" in Japanese pronunciation called oxygen.
Oxygen Chinese name is Xu Shou Qing Dynasty named. He believes that human existence can not do without oxygen, so named for the "Keeping the Spirit" or "raise gas quality", then in order to unify it with the "oxygen" instead of "support" word, which he called "Oxygen."
Nature
Under normal conditions oxygen is a colorless, odorless and tasteless gas, density of 1.429 g / l, 1.419 g / cc (liquid), 1.426 grams / cubic centimeter (solid), melting point -218.4 ℃, boiling point -182.962 ℃, in -182.962 ℃ liquefied into a pale blue liquid, solidified into snow-like light blue when at -218.4 ℃. In the periodic table of elements belonging to Group ⅥA solid valence usually 0 and -2. Ionization energy 13.618 eV. All chemical elements other inert gas can be formed outside the compound with oxygen. Oxides can generate most of the elements is heated in an oxygen atmosphere. Many elements can form more than one oxide. Oxygen molecules at low temperatures and can form a hydrated crystal O2.H2O O2.H2O2, the latter more unstable. The solubility of oxygen in the air is: 4.89 ml / 100 ml water (0 ℃), water is the basis of the living body. Oxygen in the earth's crust abundance accounted for first. 20.946% by volume of oxygen contained in the dry air; water has a composition of 88.81% by weight of oxygen. In addition to O16, there O17 and O18 isotopes.
Physical properties
It is a colorless gas; odorless, tasteless; there is a strong oxidizing power.
When atmospheric pressure 20 ℃, can be dissolved in ethanol 7 content or water content of 32.
Oxygen elemental form of oxygen (O₂) and ozone (O3). Oxygen under standard conditions is a colorless, tasteless and odorless, can help burn diatomic gases. Pale blue liquid oxygen, paramagnetic. Oxygen sorted hydrogenated synthetic water. Ozone under standard conditions is a special smell of blue gas.
The new elemental oxygen (O4): O4 is a new type of oxygen molecule an Italian scientist synthesized a molecule consisting of four oxygen atoms.
Oscillation will explode, generate oxygen: O4 === === 2O2 oscillation
It oxidizing stronger than O2.
In amounts in the atmosphere
resolve resolution:
Italian scientists using ordinary oxygen molecules and oxygen ions are positively charged, to create a o4
O4 higher energy density than ordinary oxygen molecules
O4 gold is a more expensive than gas, highly oxidized, can react with gold.
With ordinary oxygen molecules and oxygen to produce positively charged ions of oxygen molecules containing four oxygen atoms.
Such oxygen molecules can be stable, it is expected to be positive tetrahedral configuration or rectangular, from two configurations of neutral molecules O4, being a monovalent molecule O4 + and the ground state electronic structure of molecules O4- negative monovalent, and according to the principle of minimum energy determine their structural parameters, thereby obtaining O4 molecule two kinds of the ground state of the total energy of the structure, a valence ionization energy and electron affinity potential., the results of ordinary oxygen molecules O2 and ozone molecule O3 compared with the oxygen atom display O4 molecules may form a square structure or tetrahedron structure exists, which is more likely to be true square structure spatial structure O4 molecules.
Chemical Properties
Non-metallic and electrically negative after fluorine oxygen, argon, krypton, neon, helium in addition to all the elements fluorine can react with oxygen, these reactions called oxidation reaction, and a compound produced by the reaction known as oxides. In general, the vast majority of non-metallic oxide solution acidic, and alkali metal or alkaline earth metal oxide compared. In addition, almost all organic compounds can burn fiercely in oxygen and carbon dioxide is water vapor.
Valence of oxygen: oxygen valence is very special and is generally 0 to -2 valence valence. The oxygen peroxide is usually -1 price. In superoxide as -1/2, -1/3 foul oxide oxygen, superoxide oxygen valence can only say that superoxide ion, we can not look at every single atom, because the electron is quantized , there is no 1/2 electrons, valence naturally there will be no argument 0.5, ozonide, too. The regular price of oxygen is rare, and only two oxygen fluorine compound fluoride, bifluoride dioxide and acid dioxide platinum hexafluoride (O2PtF6) displayed +2, +1 and +1/2 price in high school chemistry just remember that there is no oxygen and fluorine-price on it.
Experimental results show that all metals except gold outside of the can and oxygen react to form a metal oxide, such as platinum is oxidized at high temperatures generated platinum dioxide in pure oxygen, gold is generally believed that reaction does not occur and oxygen, but Gold (III) oxide and compounds such as gold hydroxide, wherein the trivalent metal; and oxygen can not be chlorine, bromine, iodine reaction, but the ozone can oxidize them.
Brief History
In 1608, Cornelius Drebbel proved heating saltpeter (potassium nitrate, KNO3) can release the gas. This is the oxygen, but it did not identify.
Honor for his discovery of oxygen obtained by the three chemists now share: a Briton, a Swede and a Frenchman. Joseph Priestley was the first release oxygen element declaration person, in 1774 by the focus sunlight to mercuric oxide (HgO), and then collect the released gas to achieve. He noted that the candle burning brighter here, and it can make breathing easier. Priestley did not know was, Carl Wilhelm Scheele in June 1771 on the preparation of the oxygen. He wrote his findings suggest, but until 1777 was released. Antoine Lavoisier also claimed to have discovered oxygen, and he proposed that this new gas, called oxy-gène (oxy gene), which means the formation of acids, because he believed that this element is the basis of all of the acidic substance.
The main purpose
Oxygen is used extensively for smelting, refining, welding, cutting, and surface treatment of animals and plants breathe metallurgical process; a refrigerant liquid oxygen, but also high-energy fuel oxidizer. It sawdust, coal mixture called liquid oxygen explosives, is a good explosive material, oxygen and water vapor is mixed, can be used instead of air blown into the gasifier gas, gas to get high calorific value. Liquid oxygen can also make rocket propellant; oxygen is
Many of the basic components of biological processes, and therefore oxygen will become responsible for one of the necessities of any task requires a lot of space is loaded. With medical oxygen therapy, treatment of pneumonia, gas poisoning anoxia. Stone and glass products exploration, production and creation require a lot of oxygen.
Authentication method
This product enables the belt between Mars wood resurgence.
an examination
Methyl red indicator solution pH to take with each bromothymol blue indicator solution 0.3ml, add water 400ml, boil 5 minutes, let cool, get each 100ml, set A, B, C three colorimetric tube, tube B hydrochloric acid titration solution (0.01mol / L) 0.20ml, propionic acid salt tube (0.01mol / L) 0.40ml; then in acetic tube through the product 2000ml (rate per hour 4000ml), B show a tube color can not be compared with prop darker green or red armor tube tube.
Carbon monoxide take A, B two colorimetric tubes, each with lukewarm ammonia system silver nitrate test solution 25ml, A tube through the product 1000ml (rate per hour 4000ml), the comparison with the tube B, should be equally clear and colorless.
Carbon dioxide take A, B two colorimetric tubes, each with 5% barium hydroxide solution 100ml, tube B was added 0.04% sodium bicarbonate solution 1.0ml, A tube through the product 1000ml (rate per hour 4000ml), the B turbid tube compared to the display, not thicker (0.01%).
Other gaseous oxidation material to take fresh potassium iodide starch solution (potassium iodide 0.5g, add starch indicator solution 100ml dissolve, that is, too) 100ml, set colorimetric tube, add 1 drop of acetic acid, through the product 2000ml (rate per hour 4000ml) , the solution should be colorless.
Determination
FIG Instrument: A, C is the total capacity of about 300ml absorber, B is a suitable plug, D, E and I as a fine glass catheter, F is to scale precision 0.1ml, 100ml capacity is the amount of the main pipe, G for the three-way cock, H gas import and export, J balanced bottle. Before use with a rubber tube connected to the amount of the absorber pipe, which is then connected to the balance bottle.
First assay section of copper wire (diameter of about 0.8mm to take the copper wire wrapped copper wire having a diameter of about 4mm long roll and cut into sections of 10mm) filled in the absorber A, B plugged with a plug, then ammonia - ammonium chloride solution (take ammonium chloride 150g, add water 200ml, carefully add with mixing with concentrated ammonia solution 200ml, mix) to import, so full of A and C in the left part, and then saturated sodium chloride solution was injected balance bottle J, the increase in equilibrium bottle filled with saturated sodium chloride solution to make F., excess solution flowing out from the H, the amount of rotation of the trachea and G is turned absorber, the absorbent is decreased equilibrium bottle was filled with all the conduits D, E, I, and pistons G entrance, immediately close the piston, and if part of the ammonia gas - the amount of ammonium chloride solution into the trachea, it can improve the balance bottle rotation of the piston, the discharge from the H.
The cylinders connected to the test valve (designed for oxygen use), which is connected to a rubber tube outlet, carefully ajar cylinder valve, and then open the valve so that the discharge of oxygen for 1 minute, adjusted to weaker airflow. After the rubber tube and the other end is connected to the H gas import and export, as soon as the amount of pipe filled with the product, immediately turn off G and remove the rubber hose H on the import and export gas and allowed to stand for several minutes, turn the gas G ON H & Exports the balance bottle slowly lift (to prevent inhalation of ambient air, should pay attention to the balance bottle level slightly higher than the amount of liquid inside the trachea), so that the amount of liquid endotracheal Qiada scale 100ml place. G ON amount of rotation and the absorber pipe, lift the bottle so that the balance of the test into the absorber A, when a saturated sodium chloride solution through the catheter and I filled conduit D, G and closed fully vibration absorber A CAUTION shake 5 to 10 minutes, as soon as the gas is absorbed when the near complete (remaining nitrogen or other gases are not absorbed), the amount of rotation of the trachea and G is turned absorber, for reducing the equilibrium bottles, the residual gas transferred from the absorber the amount of the trachea, when the ammonia - ammonium chloride solution and filled the absorber A through conduit D, E and G when I through the piston, the piston closed.
After about 5 minutes, adjust the balance of the gas bottle level atmospheric pressure and the amount of endotracheal consistent pressure reading level scale the amount of endotracheal calculated for the content of the test sample.
In order to check whether the oxygen is completely absorbed, repeat the above operation, since the "amount of rotation G turned trachea and the absorber, lift balance bottle" since, according to operations, to the rest of the gas volume constant until the (second-order difference of not more than 0.05ml ).
Before checking or measuring, the test should be first cylinder at laboratory temperature for 6 hours or more.
Storage
Blue cylinder pressure built, stored below 30 ℃.
specification
Isotopes of oxygen known seventeen species, including oxygen oxygen -12 to -28, wherein the oxygen -16, oxygen-17 and oxygen-18 belong to three kinds of stable, other known isotopes are radioactive half-life all of which are less than three minutes. Medical cyclotron produced proton bombardment of heavy oxygen water into oxygen-18, through the (p, n) nuclear reaction, which can obtain a positron-emitting radioisotope fluorine-18 ion, for the synthesis of positron emission tomography check the required tracer FDG.
Symbol neutron proton mass (u) the amount of change in the relative abundance of half-life nuclear spin relative abundance
12O 8 4 12.034405 (20) 580 (30) E-24 s [0.40 (25) MeV] 0+
13O 8 5 13.024812 (10) 8.58 (5) ms (3 / 2-)
14O 8 6 14.00859625 (12) 70.598 (18) s 0+
15O 8 7 15.0030656 (5) 122.24 (16) s 1 / 2-
16O 8 8 15.99491461956 (16) stabilized 0+ 0.99757 (16) 0.99738-0.99776
17O 8 9 16.99913170 (12) stabilized 5/2 + 0.00038 (1) 0.00037-0.00040
18O 8 10 17.9991610 (7) stable 0+ 0.00205 (14) 0.00188-0.00222
19O 8 11 19.003580 (3) 26.464 (9) s 5/2 +
20O 8 12 20.0040767 (12) 13.51 (5) s 0+
21O 8 13 21.008656 (13) 3.42 (10) s (1 / 2,3 / 2,5 / 2) +
22O 8 14 22.00997 (6) 2.25 (15) s 0+
23O 8 15 23.01569 (13) 82 (37) ms 1/2 + #
24O 8 16 24.02047 (25) 65 (5) ms 0+
25O 8 17 25.02946 (28) # <50 ns (3/2 +) #
26O 8 18 26.03834 (28) # <40 ns 0+
27O 8 19 27.04826 (54) # <260 ns 3/2 + #
28O 8 20 28.05781 (64) # <100 ns 0+

Distribution
Oxygen the total mass of the earth's crust is 48.6% in the most abundant element in the earth's crust, which is substantially in the form of oxides present in the earth's crust. Each kilogram of seawater dissolving 2.8 mg of oxygen, and the oxygen in the water almost reached 88%. For the purposes of the whole earth, oxygen content of 15.2%. Whether human, animal or plant, they have similar biological cells, of which accounted for 65% elemental oxygen mass.
Type of poisoning
"Oxygen poisoning" generally occurs in patients with long-term oxygen in. Although adequate oxygen metabolism can improve the ability of human cells, enhance immunity, but long-term inhalation of high concentrations of oxygen can also reduce the occurrence of pulmonary surfactant, causing alveolar exudate, pulmonary edema, dizziness, paleness, rapid heartbeat and many other issues. More seriously, oxygen toxicity was not easy to be perceived, often before clinical symptoms occur within 2-3 days, then re often easily bungled rescue time. Some families often do not pay attention oxygen inhaled oxygen concentration and time, that the higher the oxygen concentration, the better, oxygen as long as possible. This increases the risk of oxygen toxicity.
Pulmonary oxygen toxicity
1, symptoms:
Similar bronchial pneumonia. Their performance and the normal development process: tracheal irritation initially similar upper respiratory tract infection, such as chest discomfort (stinging or burning sensation) with mild dry cough, and slowly increase; then after chest pain, and the pain gradually along bronchial tree spread to the entire chest, inspiratory staggering; pain gradually increased, uncontrollable coughing appear; also accompanied by shortness of breath at rest. In the early stages of the onset of symptoms of the end of the exposure, chest pain and coughing can be alleviated within a few hours.
2, the signs:
Lung auscultation, often there is no significant positive signs; the late severe symptoms can appear scattered crackles or bronchial
Breath sounds. The higher the oxygen pressure, the shorter the incubation period of these signs and symptoms.
3, laboratory tests:
⑴ X-ray examination: lung markings can be found, or lung patchy shadows.
⑵ spirometry: FVC decrease pulmonary oxygen toxicity is the most sensitive indicators.
Convulsions oxygen toxicity: the performance of oxygen toxicity seizures, can be divided into four consecutive phases:
⑴ incubation period: the length of the incubation period and the suction pressure of oxygen gas was negatively correlated, but not linear. Oxygen pressure, increased latency.
⑵ prodromal period: manifestations include: ① facial muscle twitching, the most common, mainly for the facial muscles and lips quiver; ② autonomic symptoms: sweating, salivation, nausea, vomiting, dizziness, palpitations and pale and so on; ③ paresthesia: may have reduced vision, visual hallucinations, auditory hallucinations, phantom smell, bad breath and numb extremities; ④ mood disorders: irritability, anxiety or euphoria, etc; ⑤ precursor may be the end of extreme fatigue and breathing difficulties, a few cases there may collapse occurred. Timely detection of prodromal symptoms and to take immediate measures from the hyperbaric oxygen environment, to prevent oxygen seizures occur is very important. It should be noted that the specific patients are often only one or several of prodromal symptoms, sometimes even no obvious direct prodromal symptoms convulsions.
⑶ seizure period: prodromal period, soon convulsions. ① grand mal seizures or generalized tonic-clonic spasm-like, each lasting for about 2 min; ② in person, before the onset of sometimes uttered a short scream, loss of consciousness, sometimes accompanied by incontinence; ③ EEG changes : appear before the convulsions, increased frequency and voltage increase, and appear spiny wave-spindle (spindle-like waves).
⑷ coma: If, after the occurrence of seizures is still in the high-oxygen environment, that is, into coma. Animal experiments showed unconscious, occasionally locally slight convulsions, dyspnea gradually worsened, and then continue the faint breathing until it stops. Even after the seizure staff promptly from hyperbaric oxygen environment, but also blurred some time consciousness or mental and behavioral disorders, usually in 1 ~ 2h can be restored after a few hours to sleep. Without leaving obvious sequelae.
Pathogenesis
Not yet fully understood. Mainly in the following views:
⑴ direct toxic effects of hyperbaric oxygen on tissues and organs. More specifically, when we can not find the exact mechanism of injury, the provisionally considered to be direct toxic effects of oxygen.
⑵ biofilm impaired oxygen under high pressure conditions, the alveolar wall membrane secretory cells (type Ⅱ cells) within the lamellar body damage, synthesis, secretion and function of pulmonary surfactant is decreased, causing the lung surface tension increases, resulting in atelectasis.
⑶ related enzyme inhibition hyperbaric oxygen inhibited the activity of many enzymes such as glutamate decarboxylase and Na + -K + -ATP enzyme.
⑷ role of oxygen free radicals of oxygen free radicals are a class of oxygen-containing group having a highly chemically reactive. Normally, the body of oxygen free radicals generated primarily cleared by the body's antioxidant defense system. The body is exposed to oxygen under high pressure, excessive oxygen free radicals, and much higher than the capacity of the antioxidant defense system cleared. The main oxygen free radicals cause damage to the following two aspects: 1. Biofilm lipid peroxidation; 2 destroy the protein polypeptide chain: enzymes are proteins whose activity is affected. Free radical theory can explain many phenomena of oxygen toxicity at the molecular level.
⑸ nerve - humoral factors
⑹ action of certain peptides in the brain, such as b-endorphin and arginine vasopressin.
Causes
Simply put, that causes excessive inhalation of oxygen, and the pressure and duration of hyperbaric oxygen are the two main factors that cause oxygen toxicity.
1 diving breathing high partial pressure of oxygen
When using oxygen ⑴ light diving apparatus diving more than the prescribed depth
⑵ When using ventilated air diving apparatus diving, underwater stay too long
⑶ greater depth when diving with helium were loaded with oxygen, if not required to formulate the appropriate oxygen concentration gas mixture, smoked or mistakenly shallower depths in the use of gas.
2 cabin pressure hyperbaric oxygen breathing: more than a predetermined pressure - time limit.
Factors
⑴ individual differences and individual differences Day: Sensitivity differences in different individuals of a high concentration of oxygen is very high. Even the same individual, the oxygen tolerance in different states of great volatility.
⑵ CO2: CO2 gas inhalation increased oxygen concentrations promote convulsions.
⑶ labor intensity: promote increased labor intensity of oxygen toxicity.
⑷ temperature: High temperatures can reduce the body hyperbaric oxygen tolerance. Increase low temperature tolerance to some extent, but if it is too low to cause muscle tremors, energy consumption increases, the tolerance will be reduced.
⑸ spirit of factors: mood swings, stress, lack of sleep can reduce the body hyperbaric oxygen tolerance.
Occurred while diving oxygen poisoning treatment
⑴ quickly left the high-pressure environment: prodromal symptoms appear immediately when the water rises, it should be promptly sent divers into the water when the ambulance had seizures, but to control the rising speed (<10 m / min), in order to prevent lung barotrauma.
After ⑵ water treatment: removable harness, supine rest, keep quiet, keep warm, continue to observe the anti-sudden convulsions.
⑶ anticonvulsant therapy: drug seizures occur, you should choose a smaller impact on cardiopulmonary function drugs available 4% chloral hydrate enema 50ml, 2 h after subcutaneous injection of morphine, can be used repeatedly, no more than 4 times a day. It can also be intramuscular or intravenous injection of 0.2 ~ 0.3 g amobarbital. Oxygen is often accompanied by convulsions have a certain degree of lung damage, disable inhaled anesthetics.
Pressurized cabin oxygen toxicity of treatment
⑴ through the oxygen mask of the cabin, quickly removed the mask, breathing compressed air tanks, according to the conventional air pressure.
⑵ in pure oxygen tanks, first with compressed air ventilation to reduce cabin oxygen partial pressure, and then gradually reduced spacewalk.
When ⑶ seizures, should note the following:
① prevent falls hurt or bitten tongue, may be appropriate to use an antispasmodic when necessary.
② should be noted that patients with respiratory conditions, prone to throat spasms and convulsions breath, this time can not be reduced to prevent the closed glottis causing bruised lung. Only rhythmic breathing to be restored, after the airway, before the required decompression.
③ leave hyperbaric oxygen environment, there are seizures, anticonvulsant therapy.
Pulmonary oxygen toxicity, the light and return to normal after a few hours to restore the environment; severe, as the lungs monitoring perspective, a few days to restore.