AMV(Augumented Mandatory Ventilation)
1. A concept and a purpose
( figure ; AMV
: expired volume per minute are achieved.
) of returning to usual SIMV number of times again when being usual SIMV between but the expired volume per minute of the SIMV number of times increases to the back-up number of times. recovers when becoming a hypoventilation.
AMV is the artificial respiration mode which Bear-5 was equipped with.
It may think that this ventilation form is SIMV+EMMV.
Originally, the design philosophy of the Bear series is the one to say that permits as far as it is possible of the spontaneous-respiration in the active-ventilation.
That is, it is the mechanism which permits the voluntary intake if being intake above the set flow rate and also voluntary intake lasts to intake time set equal to or more than even if it is station on the way of the active-ventilation.
AMV is the one to have applied this thought to the adaptable law of the active-ventilation and is the ventilation law which inserts an active-ventilation while respecting the free ventilation of the patient.
(Reference 6) Intake above the setting
flow rate in the active-ventilation
Even if it is station on the way of the active-ventilation, the mechanism by which intake above the setting current velocity is permissible is loaded into Erica and Elvira and the New Port series of Engstrom, too.
2. The component
When (1) goal expired volume per minute is achieved about AMV, in SIMV of the predetermined number, when not achieving (2), it is composed of 2 aspects which are SIMV with the Back Up number of times.
3. The control
1) The controlling mechanism
It is only MPU method that, at present, is practicalized.
2) The operation theory
It switches over from SIMV to SIMV with the Back up number of times if the expiration expired volume per minute of the goal isn't achieved.
Oppositely, return to SIMV from Back up SIMV is done when the expiration expired volume per minute exceeds +10%, or being "DURE" of + 1LPM or more few ones of the set value more.
As for the measurement of the expired volume per minute, it measures 20 seconds of the pasts every 10 seconds of triggers.
4. The modification
1) The setting of a goal expired volume per minute
If setting a goal expired volume per minute a little more high than in the desired-value, the frequency of the active-ventilation increases and becomes the ventilation form which suited an introduction period to the artificial respiration.
On the other hand, when wanting to cause a spontaneous-respiration, it sets an expired volume per minute, being low a little.
2) The setting of the SIMV number of times
In the expired volume per minute, when achieving a target value, SIMV of the predetermined number is done. It
sets the degree of the active-ventilation in the SIMV number of times.
3) The Back up number of times
In the expired volume per minute, when not achieving a target value, SIMV with the Back up number of times is done. The Back
up number of times is decided in the goal expired volume per minute/the setting taking air quantity of ventilation.
4) The relation between PSV and the active-ventilation
An air quantity of ventilation as much as the active-ventilation is gotten when setting PSV pressure high but only the part gets for the degree of freedom of the patient to be narrow.
There is not an opinion to have done in the help of the spontaneous-respiration, PSV, it should do by the active-ventilation or to have boiled, and was on and for it to have been decided.
5) The measurement frequency, the measurement period of the expired volume per minute
The used frequency, the basis for where the interval is the
optimal are unclear.
AMV can boldly rarely set the SIMV number of times(=the normal number of times) because it is SIMV basically but a back-up feature by EMMV is added.
It is equivalent to EMMV with the SIMV number of times=0 general conditions.
Also, it doesn't become a problem even if it is in "DURETE" a little from the optimal value for the patient in the comparative tolerance about the set value with the SIMV number of times, too.
Therefore, the possibility to be strange which doesn't merely stay in the range of 変法 of SIMV exists in AMV.
However, regrettably, clinical evaluation isn't done.
Therefore, when analyzing the possibility of AMV from the experience and the operating principle of the author, it is the one of AMV.
It thinks that it is in two which are that the mechanical active-ventilation of (2) of not being in "the automation of Weaning" and containing a handhold to the automation of the setting (the operation) of (1) resuscitator doesn't have to be an optimum about the advantage.
Also, because it rational and continuously chooses "the balance of free breathing and the active-ventilation" which is the optimal for the patient every piece of breathing, the readjustment of the ventilation condition is unnecessary even if the ventilation condition of the patient changes.
Also, the operator can set the range of the spontaneous-respiration of which to set an ambsace active-ventilation like SIMV agreed with the ability of the patient (in the range which the patient can accept).
Like SIMV+PSV, the point which is provided without the regularity the fault of AMV has two kinds of ventilation methods which don't have an active-ventilation and similarity, PSV.
Therefore, the patient can not side with the active-ventilation well often.
[Reference 7] The point of the setting of
the SIMV (normal) number of times
It sets this number of times according to the respiratory acitivity power of the patient.
When an enough taking air quantity of ventilation is gotten in PSV and moreover the taking air quantity of ventilation and the intake expiration time don't have looseness, it sets, being rather little.
When much, it sets to rather many and when there is looseness, it heads breathing of the patient in the active-ventilation.
If saying empirically, it should set about 1/2-2/3 values of the goal air changes per hour.
[Reference 8] The balance setting by the
active-ventilation and PSV
It is 15cmH in the PSV pressure.2When the enough air quantity of ventilation can not be gotten if not establishing above the O, to earn an expired volume per minute by the active-ventilation becomes smoother than PSV.
Also, both becomes a similar ventilatory-pattern when making the corrugation of the active-ventilation 暫減型 and bringing an intake flow rate close to the peak value by PSV and the sense of incongruity which the patient receives is improved.