Thursday, October 20, 2011

Taking blood samples for glucose testing

Using your ear lobe for blood sampling
Before I got better and stopped taking diabetes meds, I used to test my blood levels frequently.  As a type 2 diabetic, I always wondered why.  There was nothing to be done about the results - maybe go to the doctors and get stronger medicine, which wouldn't do anything for me health wise, but make the doctor del better.  With Dr. McDougall's and Jeff Novick's help, I lowered my blood sugar to the point where my doctor agreed that I did not need medicine.  But my blood glucose has crept up slowly over the last 4 years, and I wanted to test how a very strict application of Jeff's "plate test" (basically seeing that 95%+ of the calories on your plate is whole plant food), I am taking my fasting blood sugars again.

Modern glucose meters are amazing, and they need very small samples.  My objection to sampling is using my fingers.  I play several stringed instruments, and seem to always be doing something with my fingers.  I found it very annoying.  Some lancets are now designed to use areas such as the legs, and "suck" the blood out for the sample.  But this rarely provides as good a sample as a capillary bed.

I wanted to share here a solution that I have used, and which may benefit others.  Long ago, when I was deciding between law and medical school, a spent a one year internship as a clinical laboratory scientist which led to licensure by the American Society of Certified Pathologists.  One part of our training was in collecting samples for the tests we performed - I'm not sure if that is done much these days.

For some of the patients, it was extremely difficult to collect blood.  This was especially true for drug addicts, whose every vein seemed to be scarred beyond redemption, and very sick individuals who had much bruising from previous venipunctures.  I was frequently asked to handle some of the really difficult cases.  Although I disliked it at first, I did develop some talent, and did my research and learned from my mentors.

For some tests, we had micro assay methods, using very small amounts of blood.  We also had heparin coated and marked glass pipettes.  This was much as the modern glucose meters use today.

The lobe of the ear contains great capillary beds where smaller samples can be express with a lancet.  The ear lobe is also much less sensitive than finger tips.   It occurred to me that that would be a fine site for obtaining samples for modern glucose meters.  And it is.

At first, I collected samples from both finger and ear to make sure that they compared well.  They were virtually exact every time I tested.  I am not sure that they would be the same right after a meal, but I only tested fasting and 2 hours p.p.

The way I do it is to simply use the lanced to push firmly into the ear lobe while pressing the trigger.  If sample size is too small, you can try to express the blood droplet with your fingers.  If you are constantly qns (quantity not sufficient), you can adjust the needle deeper, try a heavier gauge, and probably the most effective is to warm the ear lobe with a hot moist wash cloth first.

The ear lobe usually heals in a day, and you have two lobes.  You can also try several different sites on the lobes.  With experience, you will figure it out.  It is a little tricky to get the test strip to the blood droplet, especially if you are older with poorer eyesight.  I use a magnifying shaving mirror and have no problem.  It might take a few tries, but if you hate using your finger tips, you might try this.

No comments:

Post a Comment