3
Adjusting the Pressure Release Valve
The pressure release valve is set to release at a rate of 3.0 mmHg/s on an arm
that is 32 cm in circumference. For arms much larger or much smaller it may be
necessary to adjust the valve so that the exhaust rate stays in the range of 2.0 to
4.0 mmHg/s. With the bulb in hand and the hose leading away from you, place
a screwdriver into the metal slot on the top of the release valve. To increase the
rate of exhaust, turn the screwdriver clockwise. To decrease the rate of exhaust,
turn the screwdriver counter-clockwise. The larger a subject’s arm the slower the
release valve will exhaust.
Using Go Direct Blood Pressure at High Altitudes (above 6,000 ft)
To record proper measurements at altitudes above 6,000 ft (0.8 atm or
609 mmHg) the pressure release valve will need to be readjusted. The pressure
release valve is set to release at a rate of 3.0 mmHg/s at sea level, where
atmospheric pressure is 1 atm or 760 mmHg. At higher altitudes, the pressure
release valve will exhaust at a slower rate. To use Go Direct Blood Pressure at
altitudes above 6,000 ft, open the pressure exhaust valve by turning it a half
turn clockwise. See the instructions above. Verify that the exhaust rate is now in
the range of 2.0–4.0 mmHg/s after making the adjustment.
Calibrating the Sensor
The sensor is factory calibrated and cannot be calibrated by the user.
Note:
If the cuff pressure does not reach 50 mmHg after 90 seconds, adjust the
exhaust rate of the pressure release valve according to the directions listed under
“Adjusting the Pressure Release Valve.”
Channels
Go Direct Blood Pressure has seven measurement channels:
l
Cuff Pressure
l
Mean Arterial Pressure
l
Systolic Pressure
l
Diastolic Pressure
l
Pulse Rate
l
Oscillations
l
Envelope
Cuff Pressure
This channel measures the pressure applied to the cuff. This channel is active by
default when the sensor is connected.
Mean Arterial Pressure
This channel reports the estimated mean arterial blood pressure using the
oscillometric method. The value is reported at the end of the run after the
pressure has fallen below 50 mmHg. This channel is active by default when the
sensor is connected.
Systolic Pressure
This channel reports the estimated systolic blood pressure using the
oscillometric method. The value is reported at the end of the run after the
pressure has fallen below 50 mmHg. This channel is active by default when the
sensor is connected.
Diastolic Pressure
This channel reports the estimated diastolic blood pressure using the
oscillometric method. The value is reported at the end of the run after the
pressure has fallen below 50 mmHg. This channel is active by default when the
sensor is connected.
Pulse Rate
This channel reports the pulse rate of the subject in beats per minute (bpm). The
sample window for the calculation is the last 30 seconds of data collection. The
value is reported at the end of the run after the pressure has fallen below 50
mmHg. This channel is active by default when the sensor is connected.
Oscillations
This channel displays the pulses found during cuff deflation. This channel is not
active by default when connected to the sensor.
Envelope
This channel graphs the peak-to-peak amplitudes of all pulses detected during
cuff deflation. The resulting graph is the "envelope" used to calculate blood
pressure parameters using the oscillometric method. This channel is not active
by default when connected to the sensor.
