Adjusting the %MinVol in ASV mode


Author: Aleh Satsishur, Simon Franz

Date of first publication: 08.09.2020

Last change: 07.09.2020

(First published 24.08.17) Removal of recommendation to adjust patient height to compensate for additional dead space.
What are the recommendations for the initial %MinVol settings in Adaptive Support Ventilation® (ASV®)?
Adjusting the %MinVol in ASV mode

Initial setting

A logical starting point is setting a %MinVol value that will result in the same minute volume as a previous mode, if applicable.

For example, the %MinVol could be set as follows:

  • Normal patient: 100%
  • Chronic hypercapnia patient: 100%
  • ARDS patient: 120%

Add 20% if the body temperature exceeds 38.5°C (101.3°F) and 5% per 500 m (1640 ft) above sea level.​

In the table shown here below the clinical workflow, you can see recommendations regarding %MinVol changes for various clinical conditions. For more information on adjustment of %MinVol in ASV mode, see your Hamilton Medical ventilator’s Operator’s Manual.

Flowchart showing ASV settings and adjustments
ASV clinical workflow
Flowchart showing ASV settings and adjustments
ASV clinical workflow


%MinVol change


Normal arterial bloodgas



High PaCO2

Increase %MinVol

Pay attention to inspiratory pressures

Low PaCO2

Decrease %MinVol

Pay attention to mean airway pressure and oxygenation status

High respiratory drive

Consider increasing %MinVol

Consider sedation, analgesia or other treatments

Low Oxygen saturation


Consider increasing PEEP and/or Oxygen