GE CARESCAPE, User Manual

Page: 229 / 548

Non-invasive blood pressure
pressures, the amplitude (which changes based on the pressure within the cuff) and
the frequency of these pulsations (which is dependent on the patient’s heart rate),
oscillometric devices can non-invasively determine blood pressure.
●
x = Time(s)
●
y = Pressures
1. Systolic (50%)
2. Mean (100%)
3. Diastolic (75%)
4. Extracted pulse wave
5. Cuff pressure
NIBP measurement technologies
The DINAMAP Classic technology measures the mean arterial pressure, then
determines the systolic and diastolic values. The technology examines pulses from the
cuff and waits for two sequential pulses equal in both frequency and amplitude. It will
not deflate the cuff until it has good data. Artifact and false pulses are rejected.
The first determination initially pumps up to a target cuff pressure of 160 mmHg for
adult, 140 mmHg for child or 110 mmHg for infant. The initial target pressure preset
can be adjusted to a lower (or higher) initial target pressure.
PDM and TRAM use the DINAMAP Step Deflation technology. During the deflation
process, the monitor measures two consecutive pulsations in cuff pressure. If their
amplitude differs by an acceptably small amount and the time interval between the
pulsations matches the previous time intervals, the pulsations are averaged and
stored along with the corresponding cuff pressure. The cuff is then deflated to the
next step (in steps of 5-10 mmHg). As the deflation occurs, oscillation waves are
assessed for strength and amplitude until the maximum oscillation amplitude or
MAP is obtained.
If either of the above criteria is not met, the cuff pressure is maintained until two
consecutive pulsations are detected that meet the criteria. Eventually, if the cuff is
maintained at one pressure step for longer than one minute or the determination time
exceeds two minutes, the monitor will time out and display an error.
2062971-001 CARESCAPE Modular Monitors 229