False Trigger Due to Fluid Build up in the Ventilator Circuit
How fluid in the circuit produces an artifact the ventilator misreads as patient effort — and how to fix that.
Before
This was a completely passive patient with devastating neurologic injury who suddenly "started triggering breaths". Note the sawtooth-like artifact on airway pressure and flow waveforms due to the reverberation of fluid pooling in the ventilator circuit. The amplitude of this artifact is high enough to meet the trigger sensitivity threshold. This explains why the ventilator marked all these breaths as patient-triggered (purple arrowheads beneath pressure waveform).
After
Note completely passive waveforms and an actual rate (left) that matches the set rate (right). No purple arrowheads are seen under the pressure-time curve.
