Pandemic COVID-19, which was provoked by a new, previously unknown coronavirus with the tricky scientific name SARS-CoV‑2, taught us to wash our hands and keep a distance of about 1.5 — 2 meters from each other. In addition, we learned that the infection predominantly affects the respiratory tract. Moreover, the lower respiratory tract predominantly suffers — small bronchi and lung tissue.
The most dangerous manifestation is pneumonia — inflammation of the lungs caused by a virus. Due to inflammation, tissue edema, the exchange of gases between the blood and the pulmonary alveoli (sacs filled with air and braided with small capillaries) is disrupted. In the alveolus, carbon dioxide is removed from the blood, which is exhaled into the external environment, and at the same time oxygen enters the blood, which is necessary for all cells of the body for metabolism.
Oxygen deficiency due to dysfunction of the affected, inflamed lungs provokes the development of respiratory failure, hypoxia (lack of oxygen) and metabolic disorders, serious malfunctions in the body.
In some cases, if the inflammation is severe and extensive, affecting a large volume of the lungs, it may be necessary to use mechanical ventilation (ventilation of the lungs) or, in especially severe cases, ECMO (extracorporeal membrane oxygenation procedure).
With the development of pneumonia (SARS caused by coronavirus), some patients, and those, according to statistics, from 10 to 15% of all hospitalized patients, can be transferred to a ventilator. Due to modern technology, the necessary oxygen saturation of the blood is maintained so that the body can fully work, maintain its vital activity, while the immune system gradually copes with the virus.
Everyone can catch pneumonia, but for some it is especially dangerous.
What is a ventilator for?
Not all people need artificial ventilation, only when a large volume of lungs is affected, severe inflammation, when the body itself simply cannot cope with the function of gas exchange — saturating the blood with oxygen and removing carbon dioxide. The problem is that during the inflammatory process, the alveoli swell, gradually fill with liquid, which makes gas exchange impossible. In this case, the respiratory function is partially or completely taken over by the ventilator.
High mortality in some countries affected by the epidemic, in particular in Italy and Spain, is due to the fact that all seriously ill patients simply do not have enough ventilators and they die from respiratory failure, sudden metabolic failures against the background of hypoxia.
Hypoxia is especially difficult for the elderly, patients with chronic diseases — heart, lung, diabetes or cancer. It is they who are at particular risk and the main candidates for mechanical ventilation.
Those people who have a mild infection cope with respiratory disorders without much difficulty, they have a small part of the lungs affected or no pneumonia at all.
In a state of moderate severity, oxygen therapy can be indicated — the use of a mask or nasal catheter, through which a gas mixture with an increased level of oxygen is supplied. If this is not enough and the level of blood oxygen saturation decreases, the question of transferring to a ventilator is accepted, which requires experienced personnel who connects to the device and monitors the condition.
How our lungs are arranged and how to understand when they are not all right
How the ventilator works
Explaining in simple terms how the ventilator works, we emphasize that this is a complex device that is used in conjunction with other equipment, a lot of necessary consumables, and auxiliary manipulations. It forcibly delivers a gas mixture (oxygen with air) to the lungs and removes the released carbon dioxide. There are several options for connecting to the device: in milder cases, it can be a face mask connected to the handset and the device. A gas mixture of a strictly specified temperature, humidity and pressure is supplied through it.
As respiratory failure increases or in cases where the respiratory muscles cannot work effectively, an endotracheal tube is placed in the patient, through which the gas mixture is fed directly into the bronchi and lungs.
When providing emergency care, if it is an ambulance delivering a patient to a hospital, or a hospital emergency department where a severe patient is admitted, a manual ventilator (or an Ambu bag) can be used. Due to it, doctors can maintain breathing until the patient is already transferred to the device (or in emergency situations — for example, turning off the light).
IVL in the hospital
The ventilator itself will not help the patient unless there is an experienced physician and nursing staff trained to work with this complex technique. In addition, often in the treatment of severe patients and the provision of resuscitation, other devices, apparatus and equipment, medicines and devices (venous catheters, laryngoscopes, infusion pumps, cardiac monitors, pulse oximeters, etc.) are also needed. Actually, doctors have a concept of an intensive care bed — this is not only the functional bed itself, but also all the equipment necessary to help a seriously ill patient, as well as the staff who work with the patient — nurses and doctors.
The best masks to protect against viruses: learning to choose
IVL at home
Although today the Internet is full of ads for the sale and purchase of a ventilator for the home, you should not believe and try to purchase these devices. It is impossible to treat seriously ill patients at home — this means knowingly dooming them to death, since a ventilator alone is not enough, and equipping an intensive care bed in your apartment is unrealistic even for a lot of money.
Portable ventilators are in ambulances (and even then not all) and they are needed to temporarily transfer the patient to artificial ventilation in order to support the patient until he is handed over to the hospital doctors.
How much and where to buy a ventilator
But do not be puzzled by the question — where to buy a ventilator. Conscientious suppliers work only with legal entities, public procurement and directly with clinics. And if this is a “black market” of equipment, there is a chance of running into scammers who, under the guise of a ventilator, will sell completely different devices that will not help save a person’s life.
Popular questions and answers
We asked questions about IVL pathologist, junior researcher, National Research Center for Pediatric Hematology, Oncology and Immunology named after N.N. Dmitry Rogachev Dmitry Abramov.
Do you need a ventilator at home? Is it possible to purchase a ventilator to treat a person at home?
Can an inexperienced person use a portable ventilator?
Can artificial ventilation harm?
If the mode of gas supply is incorrectly selected, acidosis (acidification of the blood) or alkalosis (alkalinization) is possible in almost all patients. These processes are dangerous for metabolism and must be corrected immediately. Prolonged mechanical ventilation for more than 2–3 weeks is dangerous for the development of pathological changes in many organs, including the lungs and bronchi themselves.
Another serious complication is barotrauma, damage due to incorrectly selected pressure of the gas mixture. It is especially dangerous for thin and weakened patients, children.
And all these facts once again give an answer to your question — do you need a ventilator at home. I want to urge patients once again: at the first sign of infection, consult a doctor!