Mom really doesn’t have to buy me a ventilator.

April 5

The ventilator "collective vacation" in Wuhan Thunder God Mountain hospital is waiting for disinfection and cleaning;

April 11th

The ICU ward of Jinyintan Hospital completed the clearing of COVID-19 patients;

April 14th

Thunder God Mountain hospital patients are cleared;

April 15th

Thunder God Mountain hospital officially closed the cabin

… …

At home, good news comes one after another!

Abroad, New York ordered 17,000 ventilators from China.

Even Tadpole Jun’s overseas friends said,

His mother insisted on buying him a ventilator on Taobao.

"I am so helpless. If medical ventilators can be bought on Taobao, how can there be such a shortage abroad?"

so

What is the difference between the ventilator in the hospital and the ventilator we usually say? Is it necessary for ordinary people to use medical ventilators? What kinds of medical ventilators are there?

Mom really doesn't have to buy me a ventilator.

Too long to read the version

Rescue breathing equipment can be roughly divided into:

Oxygen therapy equipment, ventilator and artificial lung (ECMO).

They have their own characteristics, and the diseases they aim at are different.

Healthy people, there is absolutely no need to buy it themselves.

Oxygen therapy equipment

When it comes to ventilators, many readers may immediately think of scenes in TV dramas. The attending doctor said, "Come on, the patient is dying." As soon as the voice fell, the nurse hurried to push the oxygen bottle. Oxygen bottles, oxygen bags and various oxygen generators on shopping websites all belong to oxygen therapy equipment.

Oxygen therapy equipment has two functions.

(1) directly provide oxygen for patients.

If we compare the human body to a jar, with one mouth sucking air and one mouth discharging waste gas, then the oxygen concentration in the jar must be kept constant because every cell needs a certain amount of oxygen. However, in some cases, the oxygen concentration in patients will drop. For example, the patient is in a plateau, and the oxygen in the air is insufficient, or the patient suffers from chronic obstructive pulmonary disease, and the trachea and bubbles are diseased, so no matter how hard he tries, he can’t breathe in too much air. What should we do? The answer is to increase the oxygen concentration in the air inlet, that is, to provide patients with higher concentration of oxygen through oxygen therapy equipment.

(2) as an oxygen source

Oxygen therapy equipment can also be connected to a ventilator as a source of oxygen. It can be seen from here that the ventilators mentioned by doctors are not the same as oxygen cylinders and oxygen generators.

Hyperbaric oxygen chamber is a special oxygen therapy equipment. In other words, it is essentially an oxygen cylinder, but it can be as big as a room. The atmospheric pressure inside is usually three times the normal pressure, and accordingly, its oxygen concentration is very high.

There are two common uses of hyperbaric oxygen chamber.

One is to deal with anaerobic bacteria, which are afraid of oxygen; The second is to treat carbon monoxide poisoning. For the human body, hemoglobin is equivalent to a trolley for transporting oxygen, and carbon monoxide can occupy hemoglobin, thus affecting the supply of oxygen. High concentration oxygen must be used to drive away carbon monoxide in order to save the patient’s life.

Because of the high oxygen concentration, hyperbaric oxygen chamber is a very prone to fire. Don’t say that playing with lighters, even static electricity accumulated on chemical fiber clothes may cause accidents. Therefore, if you need to use hyperbaric oxygen chamber treatment, you must strictly follow the guidance of medical staff.

Having said that, one more thing: all oxygen therapy equipment has a specific scope of application. Some sellers say that "regular oxygen inhalation can improve immunity and children’s performance" in order to increase the sales of oxygen generators. In fact, normal people don’t need these at all.

Noninvasive mechanical ventilation

Under normal circumstances, when inhaling, the muscles around the lungs are pulled outward to drive the alveoli to expand; Once the alveoli expand, the pressure inside is small, which can accommodate the gas from the outside. Covid-19, on the one hand, can directly damage alveoli and interfere with the expansion of alveoli, on the other hand, it will attract immune cells, and the fighting between them will inevitably cause inflammation and further aggravate atelectasis.

What should I do in this situation?

The answer is noninvasive mechanical ventilation.

Non-invasive means no wound; Machinery is the use of a ventilator; Ventilation means inhaling oxygen and expelling carbon dioxide. The motor in the noninvasive ventilator can compress oxygen, create pressure, and then, along the breathing mask, enter the patient’s lungs — — Whether the alveoli can expand or not, oxygen is directly injected into them.

Of course, this is just a general principle, which is actually much more complicated. The pressure produced by the ventilator can be positive pressure or negative pressure, which can be generated continuously or provided intermittently, and can be adjusted according to the patient’s situation; There are also many kinds of breathing masks, which can be used only for the nose, or to wrap the mouth, or to wrap the whole face of the patient.

Invasive mechanical ventilation

Pay attention to the news, and you will find that most of the ventilators mentioned recently are invasive ventilators.

The biggest difference between invasive mechanical ventilation and noninvasive mechanical ventilation is whether to establish an airway for patients. Some patients have claustrophobia and can’t accept breathing masks, some patients have facial trauma, which affects the fit of breathing masks, and some patients have a lot of sputum in their trachea, which seriously affects the effect of ventilation. Therefore, the doctor will make an incision in the patient’s trachea, insert a hose into it, and artificially establish a passage for air in and out.

Accordingly, the structure of invasive ventilator is more complicated. For example, an invasive ventilator is equipped with a battery, which can continue to work and care for patients’ lives even if the mains supply is interrupted or the emergency power supply fails in the hospital.

Therefore, the invasive ventilator is usually fully functional and can be used as a noninvasive ventilator in an emergency; Conversely, the non-invasive ventilator cannot be used as an invasive ventilator because of its limited function. This may be why most of the current foreign orders are aimed at invasive ventilators.

In vitro oxygen membrane bonding

In vitro oxygen membrane bonding is the ECMO that is often mentioned in the first two months.

Strictly speaking, it is not a ventilator.

Non-invasive ventilator and invasive ventilator are both helpers of the lung, and assist patients to breathe through masks or tracheal intubation; When ECMO is needed, it doesn’t matter whether the patient can breathe or not, it can take over breathing completely.

When using ECMO, we should first make an incision in the patient’s blood vessel to draw the blood out. Then, ECMO will expel carbon dioxide from it, inject enough oxygen and heat it properly; Finally, the blood with proper temperature and full of oxygen is sent to the patient’s blood circulation through the motor.

In other words, ECMO is equivalent to a weakened version of the time capsule, which can temporarily save the patient’s life. The key is whether doctors can find a solution to the fundamental problem in a limited time.

However, ECMO and ventilator have one thing in common: both need oxygen. During the closing period of Wuhan, many hospitals were short of oxygen because of the surge of patients. Those workers who work overtime to produce oxygen and transport oxygen are also great contributors to the fight against the epidemic.

The domestic epidemic situation has improved recently.

But before the advent of specific drugs and vaccines

Oxygen therapy, noninvasive ventilator, invasive ventilator and ECMO.

Is the most effective way for us to deal with novel coronavirus.

To make good use of them,

Not only need excellent medical staff,

But also the cooperation of manufacturing and transportation.

I hope that over time,

We can master these technologies thoroughly,

Better care for people’s health.

Mom really doesn't have to buy me a ventilator.

magpie

  Magpies can be said to be the most common birds in rural areas of Guanzhong, especially in the countryside near the northern foot of Qinling Mountains, on the big trees in front of and behind people’s houses, and among the branches on the banks of ditches in rural areas. Magpie looks very festive, with a round head, a pointed beak, a fat body, a long tail and feathers in black, white, blue and purple, which can be said to be loved by everyone. What the villagers like best is its chirping sound, which they think is an auspicious sound. "When the magpies chirp, the guests will come", which is a favorite saying in our village.

  I also like magpies for two reasons. First, I have lived in the countryside since I was a child. Magpies are more common and seen, just like my neighbors. When I am familiar with them, I am happy. Second, I think this kind of bird looks good and sounds good, unlike sparrows, which gather in groups in front of people’s eaves all day, chattering, making people upset, and sometimes harming crops and making people hate it. Nor is it like an owl, whose voice is sharp and harsh, such as a sharp instrument crossing a slate.

  In my memory, magpies are the most common in spring and winter, but they don’t seem to be seen much in summer. This may be the reason why the magpie’s whereabouts are not easy to be found in summer. In spring, magpies can often be seen in Yuan Ye, my hometown. They jump in the wheat field one by one, head by head, and look very fun; Or while chirping, slowly fly from tree to tree, and the tail feathers draw a beautiful arc. This season, magpies’ nests are also easier to find, mostly on tall poplars. Walking in the countryside, when I look up, you will see huge magpie nests, crouching peacefully among the treetops of Gao Yang willow trees, as if they were pieces of art.. The sky is pure and blue, not stained with a trace of dust. At this time, there may be wind, and the nest will gently shake with the wind.

  Although it shakes, there is no need to worry that the nest will be blown down by the wind, because magpies are masters of nesting. I have lived in the country for many years, and I have seen many bird nests, such as those of swallows, sparrows and turtledoves … I think they are not as beautiful and strong as those of magpies. Sparrows make a nest out of a mess of grass. Sometimes, they don’t even build such a simple nest, but live directly under the eaves of others or among the trees. Swallows’ nests are exquisite, but they are also built on the beams of other people’s houses, and they like to use old nests, which are neither as big as magpie’s nests nor as beautiful as magpie’s nests. As for the doves’ nests, they are mostly built in the oblique branches of the trunk of a big tree, which is not only sloppy, but also extremely unsafe. When I was a teenager, I saw more than once that the village children climbed the tree to dig out the nest of the turtledove, and the turtledove flew around the tree in shock. Magpies, on the other hand, have no such worries. Their nests are mostly at the top of big trees, and village children can’t climb them. Even if they climbed up, because the branches at the top of the tree were too thin, the children were afraid of breaking the branches and falling to the ground, and did not dare to climb to the top to dig out the magpie nest. What’s more, the villagers also forbid children to climb the tree and dig out the magpie nest. Therefore, it is very natural that magpies are more common in their hometown.

  In spring and summer, magpies are busy building nests, laying eggs and brooding, but in autumn, magpies seem to be more relaxed. This season, the young magpies have grown up, so they don’t need to be fed. There is plenty of food in the field, and they can eat without much effort. The full magpies are singing and playing in the fields, or in the big trees in front of and behind people’s houses. Only in winter, because of the lack of food and the cold weather, they seem sluggish and seem to be less active than in spring, summer and autumn. Magpies seen in winter are mostly foraging.

  I have long known that magpies like to live in exile. In the past, during those years in my hometown, I also often saw it. However, in the past twenty years, it seems that I have seen fewer magpies in the plains and Sichuan fields. Sometimes I see it occasionally, and it is often one or two, and there are no groups. And the magpie’s nest seems to be smaller than I remember. Looking at it, it is about the size of a basketball and stands alone among the treetops of a small tree. Last winter, I went to Fengyukou, Qinling Mountain to play. By the Hongcao River, I unexpectedly met a large group of magpies. They were screaming and laughing, jumping and pecking in a mountainous area. That carefree, makes me fascinated. I was excited for a long time, and I stopped in a hurry and watched it quietly for a while. At that moment, my heart seemed to have returned to my familiar hometown and my distant childhood. In a trance, I saw my kind grandmother take a big red window cut of a magpie and stick it on the pane. And outside the window, it is a place of snow, a tree of Qiongzhi.


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