Go Direct^® Blood Pressure Sensor (GDX-BP)
Specifications and User Guide

TROUBLESHOOTING
Primary Test: To confirm that the sensor works correctly, follow the steps below.
1. Launch Graphical Analysis, Graphical Analysis Pro, or LabQuest App (LabQuest 2 or LabQuest 3 only). Connect the sensor to your device.
2. Attach the rubber hose from the cuff to the connector on the sensor.
3. Wrap the cuff firmly around the subject’s arm, approximately 2 cm above the elbow. The two rubber hoses from the cuff should be positioned over the bicep (near the brachial artery) and not under the arm. Important: The arm should rest at the level of the heart, and remain relaxed throughout data collection. A desk or table can be used to support the arm. The subject must remain still during data collection. No movement of the arm or hand should occur during measurements.
4. Find the sensor indicator light, which is located in the top-right corner of the sensor label (next to the checkmark).
5. Begin data collection. Quickly and repeatedly squeeze the bulb to inflate the cuff. Continue inflating the cuff to a pressure between 150 and 170 mmHg. The sensor indicator light will flash red as the cuff is inflated. When the light flashes green, an appropriate pressure has been reached. Note: A meter in the data-collection software will also display the live pressure readings from the sensor.
6. When the light flashes green, set the bulb pump down on the table. The built-in pressure release valve will slowly deflate the cuff. The sensor indicator light will flash green as the cuff deflates.
7. When the pressure drops to 50 mmHg, you may press down on the pressure release valve to release any air remaining in the cuff.
8. When the sensor indicator light turns solid green, blood pressure parameters have been reported. Stop data collection. Note: If the sensor indicator light turns solid red, blood pressure parameters were not reported by the sensor. Repeat data collection.
9. 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” in the user manual.

HELPFUL TIPS
1. The arm and hand must remain still during measurements.
2. The arm should rest at the level of the heart and remain relaxed during measurements. A desk or table can be used to support the arm.
3. Proper placement of the pressure cuff will increase the accuracy of your blood pressure measurements. The rubber hoses from the cuff should exit over the brachial artery and 2 cm above the crease in the elbow.
4. Accurate blood pressure readings depend on the use of a cuff of appropriate size for the arm. For younger students, a smaller cuff (18 cm to 27 cm) is available (order code CUFF-SM). A large cuff (39 cm to 50 cm) is also available (order code CUFF-LG).
5. Do not to touch or move the exhaust valve during measurements.
6. Remove any clothing that may cover or constrict the portion of the arm being used.
7. For most individuals it is not necessary to inflate the pressure cuff higher than 170 mmHg. Over inflation of the cuff may cause pain and/or injury.
8. The cuff pressure displayed should be between 0 and 5 mmHg before any air is pumped into the cuff.
9. The exhaust rate should be between 2.0 and 4.0 mmHg/s. If the cuff is not releasing the air or not releasing the air fast or slow enough, refer to the user manual for instructions on “Adjusting the Pressure Release Valve.”
10. If the cuff will not deflate, check to see that the pressure release valve is not completely closed. It should be opened about four turns from the closed position.

Please be aware that blood pressure parameters will differ from person to person and even between measurements on the same individual. Do not expect to receive the same measurements on each trial since there are many factors that cause the blood pressure of the subject to increase or decrease.

RELATED TIL ENTRIES
Why are blood pressure readings unrealistic or not being reported by the software?
I have a Blood Pressure sensor. Can my students use the data from the Cuff Pressure data that is collected by the software to calculate the BP parameters?

SPECIFICATIONS
Type: Differential pressure
Range: 0 to 300 mmHg
Resolution: 0.001 mmHg
Accuracy: +/- 0.75 mmHg
Response time: 5 ms
Maximum pressure without damage: 3100 mmHg
Systolic pressure coefficient: 57% of MAP
Diastolic pressure coefficient: 74% of MAP
Pulse rate calculation:
Sample window: Last 30 s of data collection
Maximum sampling rate: 200 samples/s
USB specification: 2.0
Wireless specification: Bluetooth 4.2
Maximum wireless range: 30 m
Battery: 300 mA Li-Poly
Battery life (single full charge): ~24 hours
Battery life (long term): ~500 full charge cycles (several years depending on usage)

CALIBRATION
The sensor cannot be calibrated by the user.

RELATED VERNIER PRODUCTS
Blood Pressure Cuffs (CUFF-SM)
Blood Pressure Cuffs (CUFF-LG)