Ventilator Modes
Clinical Scenarios
Calculations
Bellows & Ventilator Hardware
Gas Exchange
100

This ventilator mode delivers a preset tidal volume while airway pressure varies.


What is VCV?

100

An obese patient undergoing laparoscopic surgery develops worsening compliance. Which ventilator mode is often preferred?

What is PCV?

100

RR = 10. What is the respiratory cycle time?


What is 6 seconds?

100

This bellows rises during exhalation.


What is Ascending (Standing) Bellows?

100

This process removes carbon dioxide.


What is Ventilation?

200

This mode delivers a preset inspiratory pressure while tidal volume changes depending on compliance.


What is PCV?

200

During VCV, lung compliance suddenly decreases. Which ventilator variable increases?


What is Peak Inspiratory Pressure (PIP)?

200

TV = 600 mL

Inspiratory flow = 24 L/min

RR = 10

What is the I:E ratio?

What is 1:3?

200

Which bellows is safer because it visibly detects a disconnect?


What is Ascending Bellows?

200

This process increases arterial oxygen.


What is Oxygenation?

300

This mode automatically adjusts inspiratory pressure to guarantee a target tidal volume.


What is PCVG?

300

During PCV, bronchospasm develops. Which ventilator variable decreases?


What is Tidal Volume?

300

TV = 400 mL

RR = 12

What is the respiratory cycle time?

What is 5 seconds?

300

This ventilator drive mechanism uses electricity only.


What is the Piston Ventilator?

300

The normal respiratory quotient discussed in lecture.


What is 0.8?

400

This spontaneous breathing mode is patient-triggered, pressure-limited, and flow-cycled.


What is PSV?

400

A patient with an LMA is breathing spontaneously near the end of surgery. Which ventilator mode is commonly used?


What is PSV?

400

A ventilator has an I:E ratio of 1:2 and a respiratory cycle of 6 seconds.

How long is inspiration?

What is 2 seconds?

400

Fresh gas decoupling directs fresh gas here during inspiration.


What is the reservoir bag?

400

A resting 70-kg adult consumes approximately this much oxygen each minute.


What is 250 mL/min?

500

This ventilator mode synchronizes mandatory breaths with spontaneous breaths to reduce breath stacking.


What is SIMV?

500

Which ventilator mode is commonly selected when weaning a patient from mechanical ventilation?


What is SIMV (or PSV, depending on the scenario).

500

TV = 300

RR = 20

I:E = 1:2

What inspiratory flow (L/min) is required?


18 L/min

500

Bellows create approximately this much automatic PEEP.


What is 2–3 cmH₂O?

500

The formula for compliance is:

Compliance = ΔV Change in volume (usually tidal volume, mL) divided by ΔP = Change in pressure (cmH₂O)

M
e
n
u