Set It Up
Rate
12-16 breaths/min
Vt set-up
VT 4 to 6 ml/kg IBW
Pressure
set 10-15 cm H2O > PIP
What causes trigger delay?
Auto-PEEP
Ventilator malfunction
Poor sensitivity setting
Does PEEP improve oxygenation or ventilation?
Oxygenation
Vt for patients without ARDS
6 to 8 ml/kg IBW
Tsang said to start with 8
Starting PEEP
Start PEEP at 10-15 cm H2O
Higher Volume
100-200 mL above Vte
What occurs when the ventilator ends the breath at a time different from when the patient’s respiratory center wants to end the breath
Cycle Asynchrony
Why do we add PEEP?
To prevent atelectasis
Prevent decruitment
Flow trigger
1 to 2 L/min
Where should Ppl be maintained?
Pplat < 30 cmH2O
High Ve
2-4 above
What causes auto-triggering?
Circuit leaks
Water in circuit
Inappropriate sensitivity
Hyperdynamic cardiac contractions
What presence of auto-PEEP is the biggest factor in which asynchrony?
Trigger asynchrony
Peak inspiratory flow
approximately 60 L/min
What improves oxygenation? Longer or shorter i-time?
PC with longer i-Tme has been associated with improvement in PaO2
with lower rates
Low Ve
1-2 below
How are the effects of auto-PEEP on missed triggering improved in the presence of dynamic airway obstruction?
In the presence of dynamic airways obstruction, the application of PEEP offsets the effect of auto-PEEP on missed triggering.
A respiratory therapist determined that a patient receiving mechanical ventilation developed auto-PEEP due to dynamic airflow obstruction. What should the the therapist do?
Decrease the mandatory rate
Pressure Trigger
−0.5 to −1.5 cm H2O
Max RR
35
High RR
10-15 above
How do you improve flow asynchrony?
Volume Ventilation:
Increasing peak flow > 60 L/min
Decreasing inspiratory time
Adjusting rise time
Match ventilator’s i-Time to patient’s i-Time
Change to decelerating flow pattern
Pressure Ventilation:
Adjusting rise time
techniques for minimizing the effects of auto-peep
-decrease I time
-bronchodilation
-secretion management
-increase artificial airway size