Low pressure means a leak in the system
A ventilator's low-pressure alarm sounds when the pressure in the circuit falls below the set limit during a breath, which means gas is escaping somewhere between the ventilator and the client's lungs. The most common cause is a disconnection in the circuit; less common causes are a cuff leak or a displaced endotracheal tube. This client is sedated and calm, his SpO2 is 95% and unchanged, and there is no air or gurgling at his mouth. In a stable client, the quickest and most likely fix is to check the circuit connections from the tube to the ventilator.
Systematic troubleshooting
The nurse traces the circuit from the client outward: the connection between the endotracheal tube and the circuit, the humidifier or heat-moisture exchanger, the tubing joints, any in-line suction catheter, and the connection to the ventilator itself. A loose joint is often found within seconds. If all connections are secure, the nurse checks the cuff pressure with a manometer and confirms the tube position by its depth marking. Throughout, the nurse watches the client; if the cause cannot be found quickly or the client deteriorates, he is disconnected and ventilated manually with a bag and 100% oxygen while help is called.
| Alarm | Common causes | First check |
|---|
| Low pressure | Disconnection, cuff leak, displaced tube | Circuit connections |
| High pressure | Secretions, biting, kinked tube, coughing, bronchospasm | Assess client; suction if secretions |
Why the other actions are not first
A cuff leak usually produces audible air or gurgling at the mouth, which is absent here, so cuff pressure is checked if the connections are intact. Suctioning treats secretions, which raise airway pressure and trigger the high-pressure alarm, not the low-pressure alarm. Manual ventilation with a bag is reserved for a cause that cannot be found quickly or a client who is deteriorating; this client is stable, and disconnecting him to bag would delay finding the leak.
Watch out! Never silence a ventilator alarm without finding its cause. When in doubt, and especially if the client is in distress, follow the rule: if the problem cannot be fixed quickly, disconnect and bag with 100% oxygen.
Exam takeaway
Key point! Low-pressure alarm: think leak or disconnection and check the connections first. High-pressure alarm: think obstruction, such as secretions, biting, or kinks. Bag the client if the cause is not found quickly or the client deteriorates.