One of the problems that is not uncommon in patients on ventilators is correcting for “vent dyssynchrony.” Vent dyssynchrony is when the patient’s demand for oxygen is not being met by the ventilator.
Why? Consider three factors:
- LENGTH OF BREATH (how long is inspiration?)
- TIMING OF BREATH (when is the switch to expiration/inspiration?)
- ADEQUATE FLOW (how big are the volumes?)
If there are problems with any of those things, dyssynchrony can result. Dyssynchrony results in those annoying beeps you hear from the vent. This is called “triggering the vent.” This can happen if:
- ineffective triggering: PEEP is too high, musculoskeletal weakness
- inappropriate triggering: tidal volume is too low, inspiratory time is too short or flow is too low, coughing or hiccups
- autotriggering: coughing, hiccups, shivering, seizures
What should you do about it? The best thing would be to correct the underlying problem. You may have to change the vent setting, the flow rate or tidal volume, or the insp/exp times. Sometimes, all you need to do is change the trigger sensitivity threshold!
As with many of my posts, I turn to Life in the Fast Lane as a reference.