Intermittent Mandatory Ventilation IMV

1. Intermittent Mandatory VentilationIMV RC 270

2. IMV is a technique which allows the patient to breathe spontaneously (setting his own Vt and rate) with supplemental O2 and to periodically get a specific number of positive pressure breaths from the ventilator. Its like being on a T-tube and the ventilator at the same time

3. Ex. #1 : IMV of 8, Vt=900 ml Eight times a minute the patient gets a 900 ml positive pressure breath from the ventilator. In between the positive pressure breaths, he breathes spontaneously at his own rate and Vt.

4. Indications/Advantages for IMV • Weaning • Using IMV to wean is no faster or better than classical weaning or any other mode • Controlling PaCO2 • IMV Ve is titrated with patient’s spontaneous Ve • Often done with neuro patients • To get a lower mean intrathoracic pressure than A/C

7. Most ventilators incorporate a demand system for IMV that allows the patient access to source gas at the rate, flow, and volume, that the patient demands.

8. INITIATING IMV • If starting with IMV, set IMV Ve as you would back-up Ve for A/C • If switching to IMV from A/C, set IMV Ve to about one half of the patient’s OBSERVED Ve when he was on A/C • Titrate IMV Ve based on ABGs and patient’s spontaneous Ve