Colin BP-S510, Руководство по эксплуатации

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General
The monitor performs Non-Invasive Blood Pressure measurements using the
oscillometric measuring technique. A notarized pump inflates the cuff to initially blocking
the flow of blood in the extremity. Then, under monitor control, the pressure in the cuff is
gradually reduced, while a pressure transducer detects air pressure and transmits a
signal to the NIBP circuitry.
When the cuff pressure is still above systolic pressure, small pulses or oscillations in the
cuff pressure begin to be sensed by the transducer. As the cuff continues to deflate,
oscillation amplitude increases to a maximum and then decreases. When maximum
oscillation amplitude occurs, the cuff pressure at that time is measured as mean arterial
pressure (MAP). The systolic and diastolic pressures are calculated based on analysis of
the oscillation amplitude profile.
Oscillometric Method
The blood pressure values are determined by measuring the small oscillations (changes)
in the cuff pressure caused by the heart’s contractions as the pressure in the cuff is
released. Colin’s measurement technology utilizes a unique deflation technique,
Dynamic Linear Deflation. This cuff deflation technique allows a Colin monitor to
measure each small change in the cuff pressure oscillations that directly correspond to
the measurement’s systolic, mean and diastolic blood pressure values.
The cuff is first increased in pressure until it reaches a pressure above arterial occlusion.
As the cuff starts to deflate, the pulse rate of the patient is determined and the deflation
speed of the cuff is modified to create a patient specific deflation speed. As the pressure
decreases, small cuff pressure oscillations are recorded that correspond to the applied
pressure of the blood under the
cuff as the heart contracts. These
oscillations increase in strength
as the cuff pressure approaches
the systolic blood pressure value.
A sudden increase in oscillation
amplitude indicates that the
patient’s systolic blood pressure
is now able to push blood
completely through beneath the
cuff. The oscillation amplitude
continues to increase as the
pressure in the cuff is decreases
until the mean blood pressure
value is reached. The oscillation
strength then starts to diminish
and finally drop off as the diastolic
blood pressure value is reached.
The oscillometric method does not determine an instantaneous blood pressure reading
like the auscultatory method employing a microphone-type auto blood pressure monitor
but, as described above, determines blood pressure from an uninterrupted changing
curve, which means that the oscillometric method is not easily effected by external noise
and electrosurgical instruments.
Note: This equipment is suitable for use in the presence of electro-surgery.