MMV (It is Minimum Minute Ventilation or Hamilton-MMV).
1. The concept and the purpose (Figure Hamilton-MMV)
The try to self-adjust the operating-pressure of PSV and to stabilize an air quantity of ventilation was begun in Hamilton Veola. Veola tried to maintain an expired volume per minute with elaborate back-up ventilator \ which operates in addition to Apnea when the expiration expired volume per minute declines, too. However, because it named this MMV (Minimum Minute Ventilation : the this manual makes Hamilton-MMV), it was confused with usual Mandatory Minute Ventilation (being EMMV originally) and it was misunderstood. Because it was compared with EMMV except the existence of back-up ventilator \ in addition to it, Hamilton-MMV had been evaluated by the unreasonableness. The mode to do PSV pressure in the self-regulation and to guarantee a taking air quantity of ventilation by PSV is called VS(Volume Support) in Servo300 and Servo i and in Saime Inc. Helia, it is called PS.TV and so on.
2. The component
(1) A spontaneous-respiration is composed from the stable H-MMV operation and the back-up operation in case of the (2)H-MMV control failure.
3. The control system
1) The controlling mechanism
It is done in MPU.
2) The operation theory
It ventilates 8 pieces of first breathing at the setting PSV pressure. Since then, based on the intake expired volume per minute for past 8 breathing, the PSV pressure is 1-2cmH about the breath.2The O fluctuates. An expired volume per minute is measured inside the main unit (the side of intake). (As for the sensor in the Y peace part, the alarm is special). PSV pressure + 0-+30cmH to be to the set value2It is 50cmH at the ( absolute value in the O range.2The ) automatic adjustment of it is done to the O. In the expired volume per minute, in the case below - 1LPM or when the anaerosis in equal to or more than 15 seconds lasts, SIMV is begun at the number of times to which the alarm sounded and it the operator set to 10 seconds later (= Called that the back-up operates by Step by Step Procedure).
4. The modification element
1) The measurement frequency, the measurement period of the expired volume per minute
It is the method which is the same as EMMV and the best interval and the frequency are unclear.
2) The degree, the index of the PSV pressure fluctuation
Details aren't published.
3) The standard, the cancellation standard which enters a back-up
The standard of the switchover is unclear. It isn't possible to return to the original mode if not manual. The development of the automatic-return-mechanism will be the following theme.
5. The advantage and the fault
The advantage is the point that the air quantity of ventilation which was stable even if the ventilating mechanism of the patient changed is supplied, but the controlling mechanism presupposes a stable spontaneous-respiration and is a defect. Moreover, the automatic-reset from the ventilation of the back-up of not being gotten if the sure ventilation which is due to the active-ventilation as the fault is not in the back-up condition to the PSV aspect be impossible. The fact that the degree of the ventilation compulsion with the normal condition can not be set like EMMV and so on