Capillary Blood Glucose (CBG)
Assessing blood glucose should be a part of every patient with altered mentation. Concerning findings for EMS professionals include readings below 60 mg/dL, and above 500-600 mg/dL. Be familiar with the Glucometer specs supplied by your service. Sometimes you might get a reading of “LO” or “HI”, the manufacturer specs will give the ranges of blood sugar levels that fall into those categories (usually under 20 mg/dL or over 500 mg/dL)
To take a CBG:
- Ensure proper PPE. Have a sharps container handy.
- Identify a finger of choice – ideally off to the side of the distal tip as it tends to hurt less.
- Clean the site using an alcohol pad & let it dry.
- Insert test strip into monitor.
- Communicate to your patient that they will feel a “poke”.
- Use your department approved lancet to puncture the site and draw blood.
- With the test strip inserted, bring the end of the test strip to the blood, and allow it to “soak up” into the strip.
- You should have a reading within 10 seconds – record the reading.
- Control bleeding as necessary use gauze and direct pressure.
*On rare occasion the patient’s fingers are so calloused that the lancet does not penetrate deep enough to obtain a blood sample, the patient’s ear lobe might be a good alternative to get blood sample with lancet
![Picture of Glucometer, a lancet poking a ring finger, placing the drop of blood from finger stick onto test strip. Placement direction of test strip into glucometer.](https://openoregon.pressbooks.pub/app/uploads/sites/322/2023/05/image25.png)
![A gloved EMT cleaning a patient's distal end of pointer finger with alcohol prep.](https://openoregon.pressbooks.pub/app/uploads/sites/322/2023/05/image26.jpeg)
![A gloved EMT wearing eye protection, using a lancet to simulate where a finger stick specimen would be obtained. Patient's distal side of pointer finger. A sterile sheet in on table under patient's arm to prevent contamination of table](https://openoregon.pressbooks.pub/app/uploads/sites/322/2023/05/image27.jpeg)
![A gloved EMT wearing eye protection, using a lancet to simulate where a finger stick specimen would be obtained. Patient's distal side of pointer finger. A sterile sheet in on table under patient's arm to prevent contamination of table.](https://openoregon.pressbooks.pub/app/uploads/sites/322/2023/05/image28.jpeg)
CBG | 1 | 2 | 3 (instructor) |
CBG Reading mg/DL | |||
Initials |
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