Weinmann BiLevel ST 22 Operating Instructions Manual page 8

Sensors recognize the pressure in the nasal mask and in the hose system as well as
any respiratory phase change (trigger moment). Accordingly the fan initializes the
IPAP and EPAP pressures set by the doctor.
Therapy modes
BiLevel ST 22 can be operated in four therapy modes: S, T, ST, CPAP. Your doctor
will set the mode required for your therapy on the unit.
In the time-controlled mode T and the assisted-controlled mode ST your doctor can
adjust the respiratory rate to within a range of 6 to 45 breaths per minute and the
inspiration time to within a range of 20 % to 67 % of the respiratory cycle.
In the assisted mode S and in the assisted-controlled mode ST your doctor can select
one of 6 trigger levels for inspiration and expiration. In the ST mode your doctor can
turn the expiration trigger off. Expiration is then time-controlled.
If the patient does not breathe into the unit in the S mode then the pressure is changed
to a minimum frequency of 6 breaths per minute.
Other functions
The Soft start function makes going to sleep easier. Your doctor sets the initial
pressure for inspiration and expiration, which is then continuously increased during
the Soft start phase until the therapy pressure is reached. The doctor can disable this
function. Or the doctor can limit the Soft start time.
BiLevel ST 22 has an auto switch-on function. If this is activated, the nasal mask can
be turned on by breathing. The unit is turned off using the on/off switch .
On the display the therapy mode and, depending on the mode, the currently applied
values for IPAP and EPAP or CPAP and respiratory rate (f) are shown. Further, the
spontaneous or mandatory (triggered by the machine) respiratory phase changes are
displayed and the pressure change shown graphically.
8
Description of unit