Medrad Veris 8600, Руководство по эксплуатации

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8 —1
8 — IBP
Theory of Operation The IBP monitoring module is intended for direct pressure monitoring
using an intra-arterial catheter, a continuous flushing system, and an
IBP transducer. The IBP module provides analog to digital conversion
of the transducer signal.
The IBP module processes continuous digital patient data that can be
displayed as waveform and numerical values. The module supports
up to two separate IBP channels simultaneously. For arterial and
pulmonary artery IBP measurements the numerical values for
systolic, diastolic, and mean pressure are computed and displayed.
Heart Rate The IBP pulse rate is used if the ECG pulse rate data is unavailable.
See “Heart Rate” on page 5-1 for more information.
Method of Measurement The IBP module uses standard invasive pressure monitoring
techniques. A bridge transducer is measured by a highly accurate
analog to digital converter. The measuring circuit uses a 5 volt
excitation voltage that provides a transfer function of 25 micro-volts
per mmHg of pressure.
The signal is buffered and brought to the A/D converter, which is
configured for a full scale signal of ±25 millivolts. The circuit has a
potential measuring range of ±1000 mmHg of pressure. This range is
restricted to -20 to +300 mmHg for actual monitoring purposes.
There is no analog amplification of the transducer signal.
The module uses a rate of 50 samples per second for each of the two
independent IBP channels. The resulting measurement resolution is
slightly less than 0.5 mmHg. The numerical IBP value is reported by
the 8600 monitor at a resolution of 1 mmHg.
Non-pulsatile IBP sites (LA, RA, CVP, or ICP) are reported as mean
numerical values. The non-pulsatile mean value is an average of the
last 200 samples taken over a period of approximately 4 seconds.
The values for pulsatile sites (ART, PA, RV, and LV) are reported as
an average of the last eight calculated values.
The IBP heart rate is reported as an average of the last 16 heart rate
values. The software also scans for sudden changes in heart rate and
overrides the averaging function when the condition occurs.
IBP Clinical Testing
and Accuracy
The invasive blood pressure module is in compliance with applied
standard IEC 60601-2-34 and has been tested to meet the
performance specifications listed in this manual. The module as
installed in the Veris monitor has been clinically tested for
performance with a variety of patients and specific disposable
invasive blood pressure transducers.