Volume Support

Question 1

What type of mode is volume supprt

Answer 1

spontaneous mdoe only (ie Adaptive PC-CVS)

Cannot be added to a combined mode like SIMV

Question 2

What type of breaths are delivered with volume support

Answer 2

Pressure limited volume targeted breath

Similar to PSV except with VS the PS level is adjusted breath-by-breath to maintain a target tidal volume

Similar to PRVC but is a spontaneous supported breath

ie. The breaths are all patient triggered and patient cycled

Question 3

Volume Support Advantages

Answer 3

Tidal volume is guaranteed over several breaths

Patient still determines rate and TI

Considered a ‘self-weaning’ mode

Works on a NEGATIVE FEEDBACK mechanism (like APV)

Question 4

Volume Support Disadvantages

Answer 4

Like PSV, there is no back-up rate

An appropriate apnea alarm setting is very important

As patient demand increases the ventilatory support decreases

This is a good thing when there is no increases WOB for the patient (ie. It’s the “self-weaning”) BUT if patient is in distress and still wanting tidal volumes higher than set then this is bad!

Question 5

Volume Support Phase Variables

Answer 5

Trigger-Pt only

Limit-Pressure limited, volume targeted

Cycle- Inspiratory flow has decreased to a predetermined amount. There is a backup time cycle

Question 6

Volume Support Settings

Answer 6

Target Vt-PS will vary to achieve this

PEEP

FiO2

Sensitivity