Introduction to the basics of ventilator
“Ventilator” – the term is coined by “Sullivan” – Sullivan, the inventor of the world’s first sleep ventilator Professor, now domestic consumers are gradually familiar with ventilators and know a lot about which brand is good and how to use which ventilator has been greatly improved, which is mainly due to the popularity of its ventilator.
Ventilators are classified according to their configuration and effectiveness and according to the progress of the process. Most of these classifications are based on the technical performance of the ventilator and have little to do with clinical use. As the ventilator becomes more and more The increasing complexity makes the exact classification more difficult, so the strict classification is not important for clinical work, but the important thing is that some different types of ventilators and some special external correlations of respiratory therapy clinical.
Introduction to the basic knowledge of ventilator-positive pressure and negative pressure ventilation
positive pressure and negative pressure ventilation
The lung is composed of the alveoli and the respiratory tract. It is done by the pressure difference, as we have learned in the chapter on ventilation on the back, normal ventilation is when the respiratory muscles contract, and as the thoracic cavity expands, the alveolar pressure decreases, forming the pressure difference between the lungs and the atmosphere, and the air flows from the upper respiratory tract to the airway. The lower respiratory tract enters the lungs. Exhalation is due to the elastic recoil of the lungs, which makes the alveoli smaller, and the pressure in the lungs is greater than the atmospheric pressure, which passively exhales the gas inhaled during inhalation. The negative pressure supplied by the ventilator through the chest cavity or the positive pressure supplied in the airway causes a pressure difference between the upper airway and the alveoli, so that the negative gas pressure difference changes the alveoli.
When infants and young children are complicated by In acute respiratory failure, after active conservative treatment is ineffective, breathing is weakened and phlegm is thick and thick, expectoration is difficult, airway obstruction or atelectasis occurs, tracheal intubation and ventilator should be considered.
The ventilator must have four basic functions, namely, inflate the lungs, convert from inhalation to exhalation, discharge alveolar air, and convert from exhalation to inhalation, and cycle back and forth in turn. Therefore, there must be: (1) It can provide the power to transport gas to replace the work of the human respiratory muscles; (2) It can generate a certain respiratory rhythm, including respiratory frequency and respiratory ratio, to replace the function of the human respiratory central nervous system to control the respiratory rhythm; (3) It can provide Appropriate tidal volume (VT) or minute ventilation volume (MV) to meet the needs of respiratory metabolism; (4) the gas supplied should preferably be heated and humidified to replace the function of the human nasal cavity, and can supply a gas higher than that contained in the atmosphere. O2 amount to increase the inhaled O2 concentration and improve oxygenation.
Power source: compressed gas can be used as power (pneumatic) or motor can be used as power (electrical). The switching of the inspiratory phase is often switched to exhalation (constant pressure type) after reaching a predetermined pressure in the breathing loop during inhalation, or switching to exhalation (constant volume type) after reaching a predetermined volume during inhalation. Ventilators have both forms.
Therapeutic ventilator is often used for patients with more complex and severe disease, requiring more complete functions, and can carry out various breathing modes to meet the needs of changes in the disease. The anesthesia ventilator is mainly used for patients undergoing anesthesia surgery. Most of the patients do not have major cardiopulmonary abnormalities. The required ventilator, as long as the ventilation volume, respiratory rate and inspiratory ratio are variable, can perform IPPV and can basically be used.
A warm reminder from experts: When patients with sleep apnea are treated with a ventilator, the air flow in the respiratory tract is faster than that of natural breathing. The inhaled airflow must be artificially increased in temperature and humidity to ensure the comfort of wearing the machine. Guaranteed treatment effect. To prevent secondary infection, disinfect the ventilator pipeline every day, and irradiate indoors with ultraviolet light 1 to 2 times a day for 30 minutes each time.
