Smiths Medical Pneupac babyPAC 100, User Manual

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504-2056A 49
(f) Indicated Priority of Audible Alarm Sounds
High Priority
Two bursts of five pulses of sound repeated at the rate of 6 times per minute, while the alarm
condition persists, in accordance with ISO 9703.
Medium Priority
One burst of three pulses of sound repeated at the rate of 6 times per minute for 60 seconds. During
the next 60 seconds the rate increases progressively to 12 times per minute.
(g) MR Compatibility Tests
Although the babyPAC 100 ventilator has been assessed to be MR Compatible under the
conditions specified in the labeling, the following detailed test information is provided to
assist the user in ensuring suitability of the device for their specific environment with a
minimum of additional testing.
Test information:
(i) Equipment
All tests were carried out on a Bruker 3Tesla actively shielded MRI system, with internal
gradient bore of 63cm diameter, situated in the Wolfson Brain Imaging Centre, Cambridge,
UK. The frequency of this machine is 125.5MHz.
A babyPAC B10 ventilator (without electronic alarms) was used for these type tests to
evaluate the pneumatic system’s MR compatibility and a paraPAC 200D was used as a
representative test model to type test the electronic alarm system. The ventilators were set
to operate ventilating appropriately sized test lungs with the relief valve and high pressure
alarms just operating during of the inspiratory phase. Inspiratory and expiratory times,
frequency, inflation pressure and peak inflation pressure were continuously monitored by
remote measurement.
(ii) Projectile Risk:
At no point along the axis of the magnetic field did the ventilators present a projectile risk
but for a distance of about 15 cm around the point of maximum field gradient (430
Gauss/cm, approx. 40cm inside the bore of the scanner), slight restraint was necessary to
prevent gentle sliding if the ventilators were rested directly on the hard surface of the
carriage.
(iii) Ventilator performance tests:
The babyPAC ventilator was nominally set to a frequency of 45 bpm and an inflation
pressure of 40 x100Pa (40 cmH
2
O). The paraPAC ventilator was set to a nominal tidal
volume of 1100 ml and 20 bpm, providing a peak inspiratory pressure of 41cmH
2
O. It was
placed, in turn, at the extreme outer edge of the table, at the mouth of the bore (168G/cm), at
the point of maximum magnetic field gradient (430G/cm, approx. 40cm in from the mouth
of the bore) and at the isocentre of the magnet (3 Tesla).
At no point could any change of set time or frequency be detected. A maximum deviation
of minus 8% was observed on the set inflation pressure on the babyPAC, but this only
occurred with the ventilator at the centre of the magnet bore at the point of maximum field
strength (3 Tesla). The electronic monitoring system operated consistently at all points in