Smiths Medical Pneupac babyPAC 100, User Manual

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by a factor of 10. CPAP operates during this extended expiratory phase in order to supply the
required concentration of oxygen to the spontaneously breathing patient.
The multifunction alarm built into the babyPAC ventilators is electrically powered by a replaceable
single cell lithium battery but the ventilatory functions of the babyPAC ventilators are completely
independent of the alarm functions and its power source.
The alarm unit is microprocessor controlled and has four preset pressure level detectors which
monitor, respectively, the gas supply pressures, the inflation pressure and operation of the
pneumatic high pressure alarm.
The gas supply pressure detectors are built into the pneumatically operated visual indicators and are
used to operate a medium priority audible alarm if one of the supply pressures drops to a level
where the indicator shows red.
The inflation pressure detector is a pressure switch which senses the pressure at the outlet connector
of the ventilator. An output signal is given to the alarm control unit whenever the inflation pressure
is greater that 10 x100 Pa. The signal is used to determine if the pressure has passed through this
threshold at least once in any 8 second period. If not, an alarm is provided in order to warn either of
inadequate inflation pressure due to a leakage or failure to cycle or that the pressure is constantly
above the threshold.
The high pressure alarm detector is used to sense if gas is being vented from the patient circuit by
the variable relief valve at the pressure set by the alarm pressure control.
The alarm unit is designed to operate from 3 volts and therefore only lithium batteries can be used.
Other batteries will fail to operate the alarm system.