Then, the rescuer pinched the patient's bilateral nostrils with his hand pressing the patient's forehead. Then wrap the injured person's lips tightly and blow smoothly under the operation of keeping the airway open, but be careful not to leak. If blowing is effective, the chest will expand and fall with the exhalation of gas.
After blowing, the mouth and lips of the rescuer leave, release the fingers that hold the nose, let the gas exhale, and at the same time turn to breathe fresh air, and then blow for the second time. Each blowing time should be no less than 1 sec for adults and 1 sec for children, with a frequency of 8- 12 times per minute.
Extended data
Before the 1960s, hand-held artificial respiration mainly used the methods of pressing the chest and raising the arm. In the late 1950s, experiments proved that the effect of mouth-to-mouth or mouth-to-mouth blowing ventilation was obviously better than pressing chest and raising arms. After the patient stops breathing, first try to blow fresh air into the patient's lungs. After the airway is unobstructed, he can smoothly blow into the patient's lungs through his mouth.
Its main function principle is: the rescuer overcomes the elastic resistance and airway resistance of the patient's lungs and chest when blowing, and blows exhaled gas into the lungs to expand the lungs. When the patient exhales, the gas is exhaled by the elastic retraction force of the lungs and chest itself.
The oxygen content in the air is 2 1%. Normal people absorb 20% oxygen in the lungs through gas exchange, and the remaining 80% oxygen is discharged as it is. The oxygen content in exhaled breath is about 65,438+06% ~ 65,438+08%. If the patient's lungs are normal, as long as the tidal volume is greater than the normal value when blowing (1 ~ 2 times the normal value)
Therefore, in any case, as long as mechanical ventilation cannot be provided to the patient immediately, while looking for and applying the necessary equipment, mouth-to-mouth or mouth-to-mouth blowing should be implemented immediately to solve the oxygen supply of the patient and relieve the symptoms of dyspnea. After the heartbeat stops breathing, the lungs are in a semi-collapsed state.
Therefore, first of all, we should give the patient two breaths slowly to expand the lung tissue and facilitate gas exchange. Whether the blowing volume is enough can be judged by observing the chest movement of the patient or the airflow exhaled by the patient. Usually, the adult's air volume should reach 1 ~ 1.2 liters to meet the physiological needs of patients, and children can judge according to factors such as age, height and weight.
It should be noted that when mouth-to-mouth or mouth-to-mouth artificial ventilation is carried out for coma patients or trauma patients, the airway should be opened by "three-step method", and the head should be tilted back moderately to keep the mouth open.
reference data
People's Network-The three life-saving skills of artificial respiration and wound hemostasis must be learned.