Blood Tests: Potential Problems

When the police arrest an individual for DUI and arrange for blood to be drawn by a nurse, phlebotomist or other qualified individual, it should in all cases in Georgia be taken from the suspect via a vacutainer.  Two vacutainers (vials with a seal or septum at the top) are included in each blood alcohol testing kit provided to police agencies in Georgia.  Each of these vials should contain two substances -sodium flouride, the  preservative, and potassium oxalate, an anticoagulent.  Each of these tubes will be  vacuum sealed, which explains why they are called vacutainers .

The vacutainers also have an expiration date, after which the vacuum seal is no longer warrantied.  The expiration date will be printed on the outside of the blood testing kit, which is basically a small cardboard box.  The truth is that only a very small handful of  phlebotomists or police officers ever pay any attention to the expiration date, because they are rarely challenged on the issue.  In addition, state crime lab personnel don’t confirm the the expiration date.

The manufacturer’s quality control procedures only require that one out of every four thousand vials be checked.  The bottome line is that there are at least three possible defects in the state’s blood test:

1. A failed septum (or seal) on one or both of the vials, which cannot be detected after the blood in a tube has been tested, because that vial has been opened.

2. Improper amount of sodium flouride in one or both of the tubes.  Since the vacutainers are rarely if ever refrigerated before being dropped off at the the Division of Forensic Sciences, the proper amount of preservative is critical. Either too much or too little can lead to a false high test result. 

3. Improper amount of potassium oxalate in either of the tubes. 

In the case of a defective seal organisms from the environment, such as candida albicans, can get in.  Unless there is enough sodium flouride in the vial, the organisms that may be in your client’s blood will grow. The most common of these is candida albicans, a yeastlike organism that has proven to be highly resistant to sodium floride. When candida albicans is in close proximity to glucose and a source of heat, it will create ethyl alcohol via fermentation.

Too much sodium flouride may cause “salting out”, which will also lead to a false high test result with headspace gas chromatography. This can occur even if there is no problem with the vacutainer, but the phlebotomist draws too little blood.

If there is not enough potassium oxalate, the blood can coagulate or “micro-coagulate” which is almost completly undectable. Because this changes the ratio of liquid to solid in the substance that is tested, and ethanol is water soluble, it can lead to a false high test result.

It can be virtually guaranteed that in any case involving a blood test the lab did not test for the presence of Candida Albicans, the lab did not check the vial seal, and the lab did not check the amount of sodium flouride or potassium oxalate in the tube.

If any of these occurred, you will in all likelihood have a false high blood alcohol concentration reported by the lab.

Written by Allen Trapp who is board certified by the National College for DUI Defense and the author of Georgia DUI Survival Guide Visit Website Written by Allen Trapp who is board certified by the National College for DUI Defense and the author of Georgia DUI Survival Guide Visit Website

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