Biocare PM-900, User Manual

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Chapter 6 Parameter Monitoring
User Manual of Veterinary Monitor --65--
while the oscillation method is based on oscillatory wave envelope of the cuff pressure, the deflation speed
and heart rate has a relatively small influence on the measuring accuracy.
3. It is statistically shown that the measured values from the oscillation method may be smaller than that from
the Coriolis sound method where the high blood pressure measure is concerned, while the values from the
oscillation method for low blood pressures may be larger than that of the Coriolis sound method. But this is
not indicating that one is superior or inferior to the other; it should be judged by comparing them with other
methods that are accurate to determine whether the measured results are accurate or not, e.g. with the output
values from invasive or non-invasive simulators. In addition, the results on the high or low side should be
statistically judged. It is suggested that the medical workers who are more familiar with the Coriolis sound
method measure make different physiological indexes for the oscillation method results.
4. Researches show that the Coriolis sound method yields the most inaccurate results in measuring low blood
pressures. While the oscillation method are unlikely to give accurate results in measuring controlled
hypertension.
5. The mean pressure in the oscillation method is directly obtained and thus it is relatively more scientific and
the mean pressure in the Coriolis sound method is obtained by adding the diastolic pressure and 1/3 pulse
pressure, thus it is purely an empirical result.
6. The accuracy of the oscillation method can be obtained by comparing with blood pressure measure
simulators, and the manufacturers generally will check and calibrate their products through blood pressure
simulators. But there are still no mature technologies to judge the accuracy of the Coriolis sound method
measure.
7. Besides, the accuracy of mercury column of mercurial sphygmomanometers directly influences the accuracy
of the Coriolis sound method measure and it is demonstrated that 13.2% domestic mercurial
sphygmomanometers have relatively large errors in their mercury readings.
8. The measure by the oscillation method is also susceptible to movement artifact (such as occasional muscular
contractions), thus relatively large deviations are obtained sometimes; but this inaccurate data can be rejected
by combining with former and next measured results.
6.5.2 Safety Information
Operating Precautions
Alike the general non-invasive blood pressure measure, it is possible that inaccurate results are obtained, or even
no results or inappropriate understanding of the results are produced when the oscillation method blood pressure
measure is used:
1. Cuff Requirements:
1) Select cuffs of desired sizes according to different animal categories: the maximum cuff pressure
shouldn‘t be more than 40 kPa (300 mmHg) for cuffs for >20 kg and 20 kPa (150 mmHg) for
＜
10 kg.
2) Before measuring, the residual air should be evacuated from the cuff.
3) The part where symbol φ is printed on the cuff should be placed where the arterial pulse is most evident
on the brachial artery for the best result.
4) It is best that the tightness of the cuff should be made so that a finger can be stuck in between cuff and
arm.
5) The lower part of cuff should be 2cm higher than the elbow joint.