GE Portrait Hub01, Руководство пользователя

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Impedance respiration
Respiration measurement limitations
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Impedance respiration is intended for patients over three years old and weighing
≥10 kg (22 lb).
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Motion artifact (such as mobile (walking) patient, shivering, and interference
from the beating heart) may interfere with the respiration measurement, reduce
the respiration rate accuracy, and/or disable apnea detection. Respiration
measurement can only detect central type apnea. Apnea cannot be detected in
the presence of any breathing effort or motion of the patient.
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The Hub must be kept in the proximity of the Wearable RR Parameter to enable
reliable MBAN connection.
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Electrical devices, such as infrared heaters, that emit electromagnetic disturbance,
may cause artifacts or disable the respiration measurement completely.
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In some rare cases the respiration rate and pulse rate values of the patient may
be very close to each other, resulting in too low respiration rate values and false
alarms.
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Irregular cardiac rhythm of the patient may cause suboptimal performance of
the respiration measurement.
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You can only use one impedance respiration measurement on a patient at a time.
Respiration measurement description
Respiration measurement is based on the variation of the bio-impedance of the
patient’s thorax. To measure impedance, the respiration sensor sends a small electric
current to the patient through the electrodes placed on the chest. Air flowing in and
out, as well as changes in geometry, change the electrical properties of the chest. The
impedance respiration waveform reflects those changes.
The following graphic illustrates how inhalation and exhalation are reflected in the
respiration waveform:
Inhale Exhale
The Hub analyzes peaks and valleys in the waveform that correspond to breaths,
calculates the frequency of the breathing in breaths per minute, and forwards the
value to the Central Viewer. The Hub also has a counter for the time since the last
breath was detected. If that time exceeds a preconfigured time limit, the monitoring
system generates an apnea alarm. Alarm limits are configurable for high and low
respiratory rate and apnea time.
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Portrait ™ Mobile Monitoring Solution
5815148-01