Mandatory Minute Ventilation

Question 1

What classification of mode is MMV

Answer 1

Volume Control IMV

Question 2

What is MMV

Answer 2

Guarantees minimum MV even when the spontaneous rate may change

If the MV ever falls below what has been set then mandatory breaths will be delivered

Only the minimum number of mandatory breaths will be delivered in order to bring the patient up to the set MV

In contrast, SIMV will always provide the set number of mechanical breaths a minute, regardless of the patient’s spontaneous MV

Question 3

When the patient maintains a MV above the set MV what mode will the vent function like

Answer 3

Pressure support ventilation (CSV-PS)

Question 4

How Does MMV Work

Answer 4

When the patient breaths above the set MV all breaths will be spontaneous pressure support breaths

If the patient is unable to meet the set MV then the vent will deliver mandatory breaths at the set Vt to make up the MV

The number of these M breaths/min depends on how much the patient is breathing on their own

If the patient is totally apneic they will get mandatory breaths at the set rate

Question 5

How is MV determined in MMV

Answer 5

Will be set indirectly through RR and Vt

Question 6

Assisted Breaths and MMV

Answer 6

Assisted breaths are technically possible if the patient made an inspiratory effort during the trigger window

Question 7

What do you set

Answer 7

Rate

Vt

PS (for spontaneous breaths)

PEEP

FiO2

Sensitivity

Question 8

MMV Mechanical Breaths

Answer 8

Phase variables will depend on whether a VC or PRVC breath type is being delivered

If the patient makes an inspiratory effort in the trigger window then the breath is considered to be assisted

Question 9

MMV Spontaneous Breaths

Answer 9

Same as PS when PS has been set