Mechanical Ventilation 2

Question 1

What is physiologic deadspace?

How is it abbreviated?

Answer 1

The sum of anatomic deadspace and alveolar deadspace

VD/VT

Question 2

How do you calculate dynamic compliance?

Answer 2

Exhaled volume / (PIP - PEEP)

Question 3

How do you calculate static compliance?

Answer 3

Exhaled volume / (Pplat - PEEP)

Question 4

What is normal static lung compliance?

Answer 4

60-100 mL/cm H2O

Question 5

When you hear “the compliance is falling” that means ___.

Answer 5

The pressure is rising.

Question 6

When you hear “The pressure is rising” that means that ___.

Answer 6

The compliance is falling or Raw is rising

Question 7

What’s the normal Raw?

Answer 7

0.6-2.4 cm H2O/L/sec

Question 8

If airway resistance is going up, Pplat will (go up/stay the same/go down).

Answer 8

Stay the same

Question 9

How do you calculate Raw?

Answer 9

PIP - Pplat

Question 10

When lung compliance decreases, ___ and ___ will increase.

Answer 10

PIP and Pplat

Question 11

How do you treat increasing Pplat?

Answer 11

Increase the PEEP and treat the underlying cause.

Question 12

How do you calculate VA (Alveolar Minute Volume)?

Answer 12

1 mL per pound of IBW to estimate deadspace.

(Tv - Deadspace) x Resp rate

Question 13

If the patient keeps triggering the ventilator when they shouldn’t, what’s one solution? (Has nothing to do with trigger)

Answer 13

Switch to SIMV.

Question 14

Whenever you put someone into IRV, what should you do?

Answer 14

Paralyze with vecuronium and sedate with a benzodiazapine.

Question 15

When you give a paralytic, you also must give ___.

Answer 15

a sedative.

Question 16

When should you switch to IRV? (x5)

Answer 16

High FiO2 (60%)
High PEEP (>15)
High PIP (>50 ch H2O)
Low PaO2
Low compliance

Question 17

What is the benefit of using APRV?

Answer 17

Improves oxygenation with lower mean airway pressures.

Question 18

Two important criteria before putting a patient into APRV:

Answer 18

Spontaneously breathing

No ventilation problems

Question 19

Before you set initial PSV, you should calculate ___ and set the pressure support at this number.
Also, how do you calculate it?

Answer 19

Calculate airway resistance. (PIP-Pplat)

Question 20

One way to correct AutoPEEP is to decrease ___ or increase ___. You can also slowly increase ___ until each pt effort triggers the ventilator.

Answer 20

Decrease I time
Increase E time
Slowly increase PEEP 1-2 cm H2O

Question 21

How can you minimize pulmonary inflammation?

Answer 21

Give steroids

Question 22

What’s VILI? Give a common example.

Answer 22

Injuries to the AC membrane.

Fat embolism is an example. (This might appear on the test)

Question 23

An additional ARDSNET strategy regarding PEEP: Start with FiO2 30%. For every ___% FiO2 increase, add ___ PEEP.

Answer 23

10%, add 2

Question 24

In permissive hypercapnea, you can allow pH as low as ___.

Answer 24

7.20

Question 25

You can eliminate wrong answers on the test by finding vent settings that are not within these parameters:

1. FiO2:
2. Rate:
3. Mode

Answer 25

1. 40-60%
2. 8-12 breaths per min
3. (Do not eliminate by mode alone)

Question 26

If you have to increase the minute ventilation, always adjust the (rate or tidal volume) before you adjust the (rate or tidal volume).

Answer 26

Adjust the rate before you adjust the tidal volume.