User manual

User Manual for Multi-parameter Patient Monitor
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First of all, the hospital should be equipped with a 100~250V power supply system with a typical grounding wire.
If big interference in ECG continues, connect one end of the grounding wire provided with this equipment to the
grounding wire on the back panel of this monitor, and the other end to the special grounding wire, water pipe or
radiator.
A common ECG plate electrode used together with this monitor has short shelf life. Generally, the shelf life is only
one month after the package is opened. When outdated plate electrode is used, due to skin’s contact impedance and
big electrode potential, the chance of interference will be increased, and the ECG baseline will have an unstable
inclination. Therefore, always use valid plate electrodes.
7.3 NIBP Monitor
7.3.1 The Principle for Measurement of Blood Pressure
Blood pressure may be measured in an invasive way (whereby the sensor will be inserted into blood vessel
directly) or a non-invasive way. The non-invasive way includes several methodologies, such as the Korotkoff
Sound Method and oscillating method. The Korotkoff Sound Method is used as a conventional way, whereby
stethoscope is used to measure the blood pressure. By the oscillating method, an inflation pump will fill the air,
and release it slowly. A computer will record change of the cuff pressure when the air is released. With this record,
the blood pressure value will be determined. First of all, make sure the signal quality judgment by computer
meets the requirements of accurate calculation (such as sudden limb movement or cuff being hit during the
measurement). If the answer is negative, give up the calculation. If the answer is positive, proceed with
calculation of the blood pressure value.
As change of the blood pressure is recorded by electric sensor, which sensitivity is much higher than that of
human ears, the oscillating method uses different definitions for measurement of diastolic pressure, mean arterial
pressure and systolic pressure from the Korotkoff Sound Method. When the oscillating method is used, the circuit
in the measuring apparatus will separate the amplitude of the cuff pressure from its change with pulsation. With