Lecture on Analytical Chemistry in BAC testing Part 11

The above is Part Eleven from a lecture given by Attorney Justin J. McShane before the North Carolina Advocates for Justice “Advanced DWI Seminar”. This seminar happened on February 26, 2010. It was organized and hosted by John K. Fanney, Esquire of Fanney & Jackson, P.C. The following is a transcript of this video:

Issues having to do with blood.

We are going to have to zip through this because I am very mindful of the time, because Fran Gengo. Poor Fran.  He is a great guy stuck up in Buffalo.

Blood cases: possible defenses that are out there. Pre-specimen collection, specimen collection, pre-analytical, meaning storage, analytical, post-analytical.

Drawing your attention to this and some highlights that are here: pre-specimen collection, where did the kits come from? How many people have actually seen blood kits and blood tubes? Raise your hand. Great, so you are familiar with this stuff. I am going to pass it around. Feel free to open it up.  Take a look at it. Here are some tubes.

You have to understand that all tubes are not the same even if they are the same color of tube top.  It does not have the same components in it necessarily. This is the gray tube top.  The one we are mostly going to be dealing with. There are additives inside it.  There are different enclosures that have to do with the different, what is called the septum or top. On the left is a hemoguard.  On the right is a rubber septum. You can take a look and get a lot of information off these tubes themselves and what they are supposed to have in them. There is a chart here.  It is inside your materials.  You can look at it in your own leisure as far as what it says is the proper draw volume, what it has inside it, the color coding, and what that represents. The most important thing for the gray tube top is to remember that not all gray tops are equal. What I mean by that is, this is how you can take a look and see how analysis is done as well. Gray tube tops have potentially two different additives in them. One is an antiglycolytic agent which means it stops cellular break down. The other is an anti-coagulating salt: potassium oxalate or EDTA.

As you can see on here, there are different make ups but most important there is a gray tube top that has only sodium chloride and does not contain potassium oxalate or an anti-coagulant. You cannot just accept that it is a gray tube top because there are different types of gray tube tops. One that is going around there says only Sodium Fluoride.  It doesn’t have potassium oxalate; this is important because of clotting.

Let’s take a look at the magic tube and its contents. Since not everyone has it in front of them, these are the two tubes that come in there.  This is the sheath needle and this is the hub. Here is a closer view of the same exact things. At the bottom you can see the additives that are there. You can visually see them. You can also see the label. This one says potassium oxalate sodium fluoride. It says 100 mg. I think we have yet a better one. It is 100 mg, 10 ml draw. That means it has 1% of sodium fluoride.  This is going to be important later. This is it at the bottom. Some people think there is nothing inside the tube. Thank you Mr. or Mrs. Phlebotomist, you just helped me win my case. You should always be able to see that inside a tube. If it is not there then you know you don’t have a gray tube top.

As I said, there are different fill volumes and you can see here that there are  mg so if you do the math you can see that it is not 1%.  There is a smaller amount there in the hemoguard. This is the septum. One of the most important things I have been doing lately is going to the lab to examine the septum because I have no life and this is what I love doing. The purpose behind it is to take a look at the puncture. It should only be punctured one time as we will see here. This is the transfer tube. That is collected and put together. The most important thing to take from this is how it is all assembled. That is it assembled. When it goes into someone’s arm.  That is what it should look like.

As you can see, there is only one prick that goes through the septum. If you see multiple pricks two things happen. No matter what, they did it wrong. You are looking for multiple entries. Other things also come in, contaminates can come in which we will go over in a minute.

It is important to know how much Sodium Fluoride is there for a magic word we are going to back to and I will mention at least three times in the limited time that I have left with you call candida albicans.

Candida albicans is a yeast. It is omnipresent. It is all over our skin. Not to gross you out, it is everywhere; you cannot get away from it. Most important, you need to know if it is 1% or less than that or 2% because there are studies that say if you have an insufficient amount of Sodium Fluoride it can cause neo-generation of alcohol, meaning alcohol inside the tube that is not your client’s fault. Think about that. It will grow alcohol inside the tube. That is not your client’s fault. That is cadida albicans and we are going to come back to that and explain it.

You have to know about the strength of the Sodium Fluoride. As an aside, very quickly, the different colors of the needle have to do with the gauge of needle. There is no consistency between manufacturers. The reason that is important is because of this, called the butterfly needle. A butterfly needle is used for two particular reasons. Number one they say for comfort because they say there are people who have needle phobias and it is a smaller gauge needle. Smaller gauge needles, when you put it in someone’s arm, it is not supposed to be such a traumatic event to them as opposed to a wide bore needle which is what we saw there. It is very different.

The other thing is, this phobia that all people who are drunk are aggressive and they don’t want to be there especially, because this state has forced blood draws. They will get some separation between them and the crazy drunk guy by using the butterfly needle. The reason that is important is because it comes down to the hose. You have your garden hose.  You turn it on, and what does it do? It makes a nice pretty pool. If you put your thumb on it to restrict the gauge, making it a smaller gauge it jets out at a higher concentration, faster. The reason that is important is the tube and the way it fills. You put on the normal needle and it fills up nice and gently, and that is the way you want it to do it because you don’t want to rupture the red blood cells. If you have a butterfly needle, it comes jetting in very quickly just like our thumb example and that can lead to what is called hemolysis. Hemolysis, red blood cells rupturing, especially in enzymatic acid testing, hospital blood testing, spells disaster because you are releasing the red blood cell and its parts and it can over report someone’s Blood Alcohol Content just because the nice phlebotomist thought they were doing a favor and doing comfort. We see that a lot where we are.

I have to skip over a couple of slides because I have only a couple of minutes left and I have a lot to talk about here.

The specimen collection is a difference between arterial and venous blood. Most of them are going to be venous blood. If you have someone in the post-absorptive phase, which Dr. Gengo will talk about and the pharmacology that goes on there, it is a wild guess. You have to remember with a venous collection it is basically your waste. It is the stuff that goes to your brain that impairs you not the stuff that comes out of your brain after it has been exposed there. A lot of researchers say that it is the equivalent of a wild guess.

Everything on the planet Earth has an expiration date.

The important thing is, the providone iodine, which is the non-alcoholic swab, even has an expiration date. You just have to know where to look for it. It is at the bottom here and it is embossed. You have to turn it around, take a look at it, that is what you are looking at and that is where it says the expiration date. This is good through 12/31/2010. You do not drink milk that is past its expiration.  You don’t serve it to your kids and you don’t want your phlebotomist using things that are beyond expiration at all.

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