Mechanical Ventilation 2 Flashcards
What is physiologic deadspace?
How is it abbreviated?
The sum of anatomic deadspace and alveolar deadspace
VD/VT
How do you calculate dynamic compliance?
Exhaled volume / (PIP - PEEP)
How do you calculate static compliance?
Exhaled volume / (Pplat - PEEP)
What is normal static lung compliance?
60-100 mL/cm H2O
When you hear “the compliance is falling” that means ___.
The pressure is rising.
When you hear “The pressure is rising” that means that ___.
The compliance is falling or Raw is rising
What’s the normal Raw?
0.6-2.4 cm H2O/L/sec
If airway resistance is going up, Pplat will (go up/stay the same/go down).
Stay the same
How do you calculate Raw?
PIP - Pplat
When lung compliance decreases, ___ and ___ will increase.
PIP and Pplat
How do you treat increasing Pplat?
Increase the PEEP and treat the underlying cause.
How do you calculate VA (Alveolar Minute Volume)?
1 mL per pound of IBW to estimate deadspace.
(Tv - Deadspace) x Resp rate
If the patient keeps triggering the ventilator when they shouldn’t, what’s one solution? (Has nothing to do with trigger)
Switch to SIMV.
Whenever you put someone into IRV, what should you do?
Paralyze with vecuronium and sedate with a benzodiazapine.
When you give a paralytic, you also must give ___.
a sedative.
When should you switch to IRV? (x5)
High FiO2 (60%) High PEEP (>15) High PIP (>50 ch H2O) Low PaO2 Low compliance
What is the benefit of using APRV?
Improves oxygenation with lower mean airway pressures.
Two important criteria before putting a patient into APRV:
Spontaneously breathing
No ventilation problems
Before you set initial PSV, you should calculate ___ and set the pressure support at this number.
Also, how do you calculate it?
Calculate airway resistance. (PIP-Pplat)
One way to correct AutoPEEP is to decrease ___ or increase ___. You can also slowly increase ___ until each pt effort triggers the ventilator.
Decrease I time
Increase E time
Slowly increase PEEP 1-2 cm H2O
How can you minimize pulmonary inflammation?
Give steroids
What’s VILI? Give a common example.
Injuries to the AC membrane.
Fat embolism is an example. (This might appear on the test)
An additional ARDSNET strategy regarding PEEP: Start with FiO2 30%. For every ___% FiO2 increase, add ___ PEEP.
10%, add 2
In permissive hypercapnea, you can allow pH as low as ___.
7.20
