A ventilator is an important medical tool used to artificially ventilate patients. It is also called a respirator.
What is a ventilator?
A ventilator refers to a technical device used to give artificial respiration to people. In medicine, the device also bears the name respirator. A ventilator is understood to be a technical apparatus that is used to ventilate people. In medicine, the device also bears the designation respirator. The instrument is driven either pneumatically or by microprocessor control. It is used to treat patients whose breathing is insufficient or has even stopped completely. From a ventilator, a positive pressure is generated within the pharynx (nasopharynx) via a tracheal cannula. This allows the lungs to receive incoming air. The air is exhaled by the retraction forces of the lungs. For safe operation of the ventilatory function, the ventilator handles both the inhalation process (inspiration), the exhalation process (expiration), and the alternation between the two processes.
Forms, types, and styles
Depending on the area in which a ventilator is used, a distinction must be made between different types. Thus, there are emergency respirators, intensive care respirators, home respirators and tank respirators. Emergency respirators are also known as transport respirators. They are primarily used by rescue services and in intensive care medicine for transporting patients to an operation. For this reason, emergency respirators have robust equipment. Important parameters such as the breathing time ratio or the oxygen concentration can be set on some transport ventilators. They ensure short-term ventilation, which is usually volume-controlled. Intensive care ventilators are ventilators used for prolonged breathing treatments. They are used under intensive care conditions and provide all forms of ventilation. An intensive care ventilator is equipped with various alarm, measurement and documentation options. In addition, the devices can be better adapted to the patient as well as his illness. In addition, connection to a network is possible. Home respirators are ventilators that are used in the patient’s own home. In this case, there is reduced self-breathing due to disorders of the respiratory muscles or the nervous system. Nevertheless, the patient can leave the hospital again and continue ventilation at home. The design of home ventilators is smaller than other forms, which allows them to be installed in the patient’s home without difficulty. In addition, home ventilators are easy to operate and transport. Early ventilators include the iron lung, which is categorized as a tank respirator. Here, the patient lies up to the neck in the iron lung, which encloses him or her in an air-tight manner. Ventilation is achieved by creating negative pressure inside the chamber.
Structure and mode of operation
A ventilator is composed of various components. These include a patient system, which includes breathing tubes, valves, and humidifiers; an electronically powered control and drive system; and a gas mixing device to mix and supply breathing gas. Another important component is an operating and monitoring unit. In principle, a respirator is controlled by flow or pressure generators. In the case of flow, a mixture of breathing gas enters the lungs at a flow rate that is set in advance. Even if the lung resistance changes, the preset volume can be reproduced. With this method, it is possible to variably ventilate the respiratory volume past the lungs. If a pressure generator is used, a fixed pressure is applied to allow insufflation of the breathing gas. The insufflated volume decreases as the airway pressure increases during inspiration. If an acute increase in airway resistance occurs, this results in a decrease in insufflated volume. If there is a leak in the ventilation system, such as an insufficient tube block, the ventilator will still make an attempt to reach the previously set pressure, resulting in better ventilation.The ventilator has the ability to direct the control of ventilation according to time, volume or pressure. In this way, maximum values can be determined for inspiration. When this value is reached, the transition to expiration begins. With volume control, inspiration continues until a defined inspiratory volume is reached. With a timed respirator, the device performs inspiration according to a schedule that is set in advance.
Medical and health benefits
The use of ventilators is an indispensable part of modern medicine. Thus, the vital instruments are used to support or replace the patient’s spontaneous breathing. They are primarily used in intensive care and emergency medicine as well as in anesthesiology. The first attempts at artificial respiration were already made in ancient times. From 1763 onwards, flexible metal tubes were used for intubation. At that time, doctors filled the lungs with air using a bellows. 1876 saw the first use of the iron lung, which supplied patients with oxygen by creating negative pressure. It is considered the beginning of respiratory therapy proper. Ventilators are used when the patient’s safe breathing and oxygen supply cannot be guaranteed. This can be the case during a coma or after a cardiovascular arrest, among other things. Other possible applications include COPD (chronic obstructive pulmonary disease), brain damage, neuromuscular diseases associated with respiratory dysfunction, and chest deformities. Similarly, a respirator can serve well in cases of massive obesity. Respirators also play an important role in the performance of extensive surgical procedures. During general anesthesia, for example, the patient’s respiratory function is reduced, so that a machine supply of oxygen is temporarily required. Respirators are also frequently used in intensive care units.