User's Manual

Patient Monitor User Manual Monitoring NIBP
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WARNING
8 Make sure that the air conduit connecting the blood pressure cuff and the monitor is
neither blocked nor tangled.
9 Do not attach the cuff to a limb being used for IV infusions as the cuff inflation can
block the infusion, potentially causing harm to patient.
NOTE:
1 It is suggested that the user should not start NIBP measuring when the low battery
displays, or the monitor may be turned off automatically.
2 If you spill liquid onto the equipment or accessories, particularly if there is a chance
that it can get inside the tubing or the measurement device, contact your service
personnel.
3 Continuous use of the automatic measuring mode for short intervals may lead to the
discomfort of patient.
12.3 Introducing the Oscillometric NIBP Measurement
Oscillometric devices measure the amplitude of pressure changes in the occluding cuff as the cuff
deflates from above systolic pressure. The amplitude suddenly increases as the pulse breaks
through the occlusion in the artery. As the cuff pressure decreases further, the pulsations increase
in amplitude, reach a maximum (which approximates to the mean pressure), and then diminish.
12.4 Measurement Limitations
Measurements are impossible with heart rate extremes of less than 40 bpm or greater than 240
bpm, or if the patient is on a heart-lung machine.
The measurement may be inaccurate or impossible in the following situations:
z A regular arterial pressure pulse is hard to detect.
z Patients with cardiac arrhythmias.
z Patients with excessive and continuous movement such as shivering or convulsions.
z Patients with rapid blood pressure changes.
z Patients with severe shock or hypothermia that reduces blood flow to the peripheries.
z Patients with obesity, where a thick layer of fat surrounding a limb dampens the oscillations
coming from the artery.
z Patients on an edematous extremity.