Ventilators offer audible and visual alarms to alert the caregiver to changes in key patient and ventilator functions and settings. These alarms prompt a timely response, safeguarding the patient and proper functioning of the ventilator.
Note: It is critical that whenever an alarm occurs, the caregiver evaluates the patient first before checking the ventilator.
High airway pressure alarms
These are also referred to as high inspiratory pressure (HIP) alarms. This alarm setting also provides a pressure limit function.
If the ventilator pressure reaches the set limit, an audible or visual alarm activates. The ventilator will temporarily stop the inspiration, allowing the patient to exhale immediately.
The alarm detects abnormally high inspiratory pressure and may activate in response to:
Kinks in the patient circuit or tracheostomy tube
Water in the ventilator circuit
Increased mucus or other secretions blocking the airway
Bronchospasm, or narrowing of the patient's airway
Coughing, gagging or fighting the ventilator breath
Pneumonia or other changes in lung condition that affect airway resistance or lung compliance
After determining the condition that triggered the alarm, do whatever is needed to fix the situation, which could be suctioning the patient, repositioning the tube or adjusting the alarm settings. If the patient's condition has worsened because of pneumonia or other illness, contact the physician promptly.
Low airway pressure alarms
These are also referred to as low inspiratory pressure (LIP) alarms.
These alarms are in response to:
Decrease in lung pressure due to a change in lung or patient condition
Increase in patient demand for oxygen because of agitation, pain or discomfort
Change in lung compliance or airway resistance
Low pressure alarms can also activate if there's an air leak out of the breathing circuit caused by:
Patient-ventilator disconnection
Improper inflation of the tracheostomy tube cuff
Poorly fitting noninvasive nose masks or prongs
Loose circuit and tubing connections
Water condensate in the circuit
High and low rate alarms
A low or high rate alarm will trigger an audible and/or visual alert. An agitated or fatigued patient can have an increase in respiratory rate. Sedated patients or patients with impaired neuromuscular function can have a decreased respiratory rate.
High and low volume alarms
In addition to a high respiratory rate, high volume alarms may indicate increased patient demand for gas/air because of pain, anxiety or improper ventilator settings.
Low volume alarms are typically caused by air leaks. In pressure-based ventilation, these alarms may indicate worsening airway resistance or lung compliance.