Dräger Cato Instructions For Use Manual page 134

Descriptions
SIMV
Trigger and spontaneous breathing times forSIMV mode:
T
Trigger
T [sec]
Spont
5
4
3
2
1
1 2 3 4
Maximum pause time
Example:
f = 5 per minute
IMV
f =10 per minute
IPPV
1 1
∆T = ––– – ––– = –––––––– – ––––––––– = 6 s
f f 5 per min.
IMV IPPV
From the diagram we can see that:
T = 3.5 seconds and
Spont
T = 2.5 seconds
Trigger
During the trigger time, the system checks whether the
airway pressure drops at least 1 mbar below the
pressure measured at the end of the expiration phase.
The mandatorily applied minute volume may increase
if an automatic ventilation stroke is applied at the
beginning of each trigger period!
The duration of a mandatory stroke plus the spontaneous
breathing time is calculated as follows:
1
–––– + T = 6 s + 3.5 s = 9.5 s
Spont
f
IPPV
This corresponds to a frequency of approx. 6 per
minute and the applied minute volume increases to
6 per minute · V .
T
134
T
Spont
T
Trigger
Example
∆T [sec]
5 6 7 8 9
1 1
10 per min.