baxter ARENA - Troubleshooting

12. Pressure Monitoring
The NIBP Monitor uses the oscillometric method of noninvasive
blood pressure measurement. The Monitor measures the systolic,
diastolic, and mean blood pressures, and the average heart rate.
The cuff automatically deflates to 165 mmHg during the first blood
pressure reading or after a blood pressure error. During the next
blood pressure reading after a successful reading, the cuff
automatically inflates to the previous systolic pressure plus 30
mmHg. An overpressure switch automatically deflates the cuff at
approximately 330 mmHg.
12.3.2 Troubleshooting
When the cuff is inflated to a target pressure (higher than the
patient’s systolic pressure), the oscillometric NIBP Monitor looks
for a pulse, which is detected as small fluctuatoins in the cuff
pressure. Since patient movement can also cause small pressure
fluctuations, the pulse is “screened” by looking for similar pulses
within a range of normal pulse frequencies.
If the monitor is unable to detect a “screened” pulse, a no reading
error code is transmitted and displayed on the Arena Instrument
screen as 905: No Reading.
The most common cause of 905: No Reading errors is movement.
This can be corrected by making sure the patient and connecting
hose are still during the reading.
Some conditions that cause inconsistent pulses are correctable.
The cuff must be properly sized, properly aligned over the
artery, and fit snugly when deflated.
•
•
•
•
•
Loose or thick clothing may cause problems in locating a pulse
signal.
Pressure fluctuations can be transmitted to the monitor from
the hose. The hose must be unobstructed and free of kinks and
tangles.
Low target cuff pressure and high patient blood pressure can
cause errors. If the target pressure is lower than the patient
systolic pressure, the monitor may misinterpret pulse
fluctuations and return a 905: No Reading error. A cancelled
reading or error condition resets the target cuff inflation
pressure to 165 mmHg.
Patient conditions such as allorhythmic pulse (pulse with a
repeating irregularity) and bigeminal pulse (a pulse beat that
occurs in pairs), old shunts, and medications may cause
157-1278-919 Rev A 12-15
April 2004