Adaptive Support Ventilation

Question 1

ASV

Answer 1

An optimal control type of closed loop mode

Sophisticated form of MMV

Question 2

Goal of ASV

Answer 2

Provide MV while maintaining the WOB and avoiding ineffective breathing patterns

Based on the assumption that the optimal breathing pattern should result in the least amount of WOB and the least amount of pressure supplied by the vent

Question 3

Ineffective Breathing Patterns

Answer 3

Rapid and shallow

Breath stacking

Excessively large breaths

Excessive dead-space ventilation

Question 4

How Does ASV Work

Answer 4

The vent will monitor the lung charateristics and then the vent will optimize the frequency and later pressure to achieve the desired Vt in order to minimize WOB

The vent will do this by dleievring a mix of PC and PS breaths depending on patients drive to breath

Question 5

Ventilator Breaths Are

Answer 5

Based on operator set % minute vol

Mandatory breaths are PRVC

Spontaneous breaths are Pressure supported and volume targeted

Question 6

How does the vent measure lung characteristics for ASV

Answer 6

Will measure through •Ti, Te, total RR, VE insp, RC exp, Raw, Compliance

Question 7

ASV Set Up

Answer 7

Determine IBW through height and gender

Set %MinVol

Set Tube Compensation (100% compensation)

PEEP/CPAP

FiO2

Question 8

% Min Vol

Answer 8

Based on 100 ml/kg IBW for 100% setting

Normal pt= 100%, COPD = 90%, ARDS 120%

Add extra for hyperthermia

10% per degree C^O ↑

Add extra for altitude

5% per 500 m above sea level

Question 9

If adding an HME what should you do for IBW

Answer 9

Add 10% to IBW due to increase in deadspace

Question 10

Monitoring ASV

Answer 10

Question 11

Monitoring ASV-Vent Status Panel

Answer 11

Question 12

ASV – Is it lung protective?

Answer 12

ASV uses rules to limit frequency and VT combinations

The operator input sets the absolute boundaries

HPL, IBW

Internal calculations from patient measurements narrow the limits further

Question 13

High VT Limit

Answer 13

HPL -10cmH20

Pt height (22ml/kg max Vt)

HPL – 10 cmH20 = max pressure, remember we always want Pplat< 30

Question 14

Low Vt Limit

Answer 14

4.4ml/kg IBW

Question 15

Low-Frequency Limit

Answer 15

Vent only

5 bpm

Question 16

High-Frequency Limit

Answer 16

Vent only

fmax= Target MV / minVT

RCexp taken into consideration

Question 17

Managing Severe Acidosis

Answer 17

Increase PEEP and/or FiO2

increase %MV

Question 18

Managing High Oxygenation Needs

Answer 18

Increase PEEP and FiO2

Question 19

Managing High Respiratory Drive

Answer 19

Increase % MV

Question 20

Managing Respiratory Alkalosis

Answer 20

Decrease % MV

Question 21

Managing Respiratory Acidosis

Answer 21

Increase % MV

Question 22

ASV and Cardiac Surgery

Answer 22

Post cardiac surgery patients on ASV required shorter time of mech vent than with SIMV + PS