Mechanical Ventilation Flashcards
3 T’s of mechanical ventilation
Trigger, Target, and Termination
Mode of ventilation where a tidal volume and inspiratory time are set and the inspiratory pressure changes to achieve the desired tidal volume
Pressure Regulated Volume Control (PRVC)
Mode of ventilation where vent provides pressure during inspiration in proportion to the electrical activity of the diaphragm
Neurally adjusted ventilatory assist (NAVA)
2 types of trigger related asynchrony
Ineffective trigger, double trigger
Breath delivery asynchrony is called what
Flow asynchrony
2 types of cycling related asynchrony
Delayed termination, premature termination
1 type of exhalation related asynchrony
Intrinsic PEEP
Method of fixing double trigger asynchrony
Increase the inspiratory time
Most common cause of ineffective trigger asynchrony
Auto-PEEP
3 factors that increase risk for failure with extubation
- Poor cough
- Heavy secretions
- Unable to do 4 tasks (open eyes, follow eyes, grasp hand, stick out tongue)
Difference between peak and plateau pressures that suggests compliance rather than obstruction
<5 cm H20
Double triggering
Patient is exhaling before ventilator is set to terminate the breath. Inspiratory time needs to be reduced.
Acute obstruction shown by increased resistance. Peak pressure increases while plateau remains the same.
Large air leak from ET tube cuff failure. 500 ml Vt in but only 300 ml out with a marked drop in plateau pressure. Also note the volume tracing sharply drops down because it is an automatic return to zero with each breath.
A - Airway obstruction. Loss of volume with expiratory flow is slow
B - Decreased compliance. Loss of volume with a rapid expiratory flow.
C - Circuit leak. Inhaled volume intact but return volume is less.
Flow Asynchrony.
Pressure curve “flattens” after initiation of breath.
