Abstract: Mechanical ventilation is an effective means of life support and respiratory therapy, has been widely applied in clinic fields. Especially in recent years, the construction of the emergency in two level of first-class hospital and ICU established, ventilator applications gain popularity. Ventilator alarm is a frequent problem in mechanical ventilation, if handled improperly, not only affect the ventilator’s using, but also endanger the patient's life. So correct judgment and timely remove alarm is very important. Clinical medical staff who are not very familiar with ventilator application will feel the tension and pressure on ventilator alarm, even feel be at a loss, they can not be quickly make sure the reasons and perform the correct treatment .This paper analyzes the reasons of ventilator alarm in order to help doctors and nurses to handle the common reasons ,and further improve the success rate of resuscitation of critically ill patients.

Key words: ventilator, alarm, treatment