Welch Allyn OSZ4 Series, Directions For Use Manual

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2 Semi-Automatic Blood Pressure Monitor Welch Allyn
• In cases of cardiac irregularity (arrhythmia), measurements
made with this instrument should be evaluated only after
consultation with the doctor.
Electromagnetic interference:
The device contains sensitive electronic components (a
microcomputer). Therefore, avoid strong electrical or
electromagnetic fields in the direct vicinity of the device (e.g.,
mobile telephones, microwave ovens). These can temporarily
impair the measuring accuracy.
Important information on the subject of
blood pressure and its measurement
How does high/low blood pressure arise?
The level of blood pressure is determined in a part of the brain,
the «circulatory center», and adapted to the respective situation
by way of feedback via the nervous system. Blood pressure
changes when the strength and pulse rate of the heart and the
width of circulatory blood vessels are altered. Blood vessel width
is affected by the fine muscles in the blood vessel walls.
The level of arterial blood pressure changes periodically with
heart activity. During the blood ejection (systole), the value is
maximal (systolic blood pressure value); at the end of the heart's
rest period (diastole), it is minimal (diastolic blood pressure
value). The blood pressure values must lie within certain normal
ranges to prevent particular diseases.
Which values are normal?
While there is no «normal» blood pressure or one combination of
systolic or diastolic pressures which is right for everyone, it is
generally accepted by physicians that 120/80 is a healthy blood