Ventilator Basics

Question 1

What is normal MV?

Answer 1

5-10 L/m

Question 2

How can we minimize lung damage? (4)

Answer 2

1. Keep transpulmonary pressures low
2. Keep mean airway pressure < 28 cmH2O
3. Keep drive pressure < 15 cmH2O
4. Use open lung ventilation

Question 3

What is the purpose of mechanical ventilation? (2)

Answer 3

1. To artificially move gas into and out of the lungs
2. Support insufficient spontaneous ventilation (breathing)

Question 4

What are the goals of mechanical ventilation? (5)

Answer 4

1. Improve gas exchange
2. Relieve respiratory distress
3. Improve pulmonary mechanics
4. Permit lung and airway healing
5. Avoid complications

Question 5

When do we apply mechanical ventilation? (4)

Answer 5

1. Acute vent failure (CO2 problem)
2. Impending vent failure
3. Severe hypoxemic failure (O2 problem)
4. Prophylactic vent support

Question 6

What is a normal P/F ratio?

Answer 6

> 380 mmHg

Question 7

What is the absolute contraindication of mechanical ventilation?

Answer 7

Untreated tension pneumothorax (must decompress with chest tube first)

Question 8

What are the 2 types of vents?

Answer 8

Volume control and pressure control

Question 9

What are the 2 modes of vents?

Answer 9

Full vent support or partial vent support

Question 10

What are the 3 types of full vent support and what do they do?

Answer 10

1. CMV - patient is not able to trigger a breath
2. A/C (assist control) - patient triggered or time triggered breaths - machine does all the work once the breath is triggered
3. SIMV- spontaneous and mandatory breaths depending on the pts needs

Question 11

What are the 3 types of partial vent support and what do they do?

Answer 11

1. CPAP - preset pressure is maintained in airways and patient controls rate and depth
2. PSV - used with spontaneous modes to assist spontaneous breaths
3. SIMV - with spontaneous breathing

Question 12

What is the number one trauma associated with mechanical vent?

Answer 12

Barotrauma

Question 13

What levels increase the risk of barotrauma?

Answer 13

PIP - >50 cmH2O
Plateau or mean airway pressure - > 30 cmH2O
PEEP - > 10 cmH2O

Question 14

What are other hazards that could cause barotrauma?

Answer 14

Increased time of the ventilator or severe lung pathology (COPD, lobectomy, etc.)

Question 15

Decreased ______ and _______ are a hazard of mechanical ventilation.

Answer 15

Cardiac output and blood pressure, which puts more pressure on the mediastinum and unintentional gas trapping (Auto PEEP)

Question 16

How do you find the PPlat on the ventilator?

Answer 16

You get a static hold by pushing the first lungs

Question 17

How do you find the autoPEEP on the ventilator?

Answer 17

You push the second lungs on the machine