Lecture on Analytical Chemistry in BAC testing Part 7

The above is Part Seven 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:

One of the questions that gets asked sometimes is “Why can’t the machine test whole blood?” The reason why it can’t test whole blood, I’ll explain here in a minute, it’s the way it’s set up. When you do hospital blood tests it’s an enzymatic method involving a reagent. It’s colorimetric and spectrometry based upon Beer’s law.  And what does that mean? The most important thing to take away is this slide up here.

It is not selective and it’s not specific.  What I mean by that is it is not something much different than this right here. This is not selective. It’s not specific. It’s so bad that if you had dark chocolate, I’m from nearby Hershey – I didn’t bring down a Hershey bar this time.  If you put a Hershey bar in this thing, you put crushed up Tylenol PM inside of here, you put in a lot of things it can put in a false positive. Same thing that happens here.

And the biggest source of interference is by what’s called lactate and we are going to show you why lactate is what you are looking for. Ringer’s lactate is an IV solution that’s given during trauma or when they think someone is going to go into shock. If you have ever seen any of the ER shows it’s sitting there and they are giving it in the person’s arm, and they are carrying through and everything like that. It’s called fluid resuscitation and what it does is it’s pumping through a bunch of electrolytes and lactate in hopes that you don’t go into shock and not die of your injuries but die of shock. It is almost universally used in every single accident case that is out there and any sort of injury that is out there.  But it gets better than that. It gets infused, and what I mean by that is they oftentimes put them in both arms and they set it there, and they squeeze the bags in order to get it into the blood as quickly as possible. That is how you get the administration of lactate.

So what you need to do is when you have an accident case that involves an emergency room and enzymatic assay test, hospital blood testing (and that is how they are trying to get your client) what you need to do is you need to take a look at the admission charts that go in there because they should be recording what’s in each person’s arm and body as they come in.  But more importantly the most useful that I find is subpoenaing the ambulance crew and they have their own documentation that is out there, and also their replacements so you can know specifically.  Because as soon as they are done using their Lactated Ringers they have to order a new one. That is the type of thing that you should be taking a look at.

Two other things, what else releases lactate? Trauma. Soft tissue trauma. Heart tissue trauma.  If you are in a car accident and you break your leg, especially your femur then it will release lactate. If you are beat up, if it is soft tissue damage inside, like the steering wheel hits your ribs and cracks your ribs and hurts, you that can release lactate. Remember the words TCA? TCA is where they got the deproteinizing agent.  Believe it or not is the very process of adding TCA, you release lactate.  So think about that. That means that every single time that you are using TCA you are going to be jacking up your BAC result.  Tell me how fair that is. It is impossible to tell what is alcohol and what is lactate and I will show you why. The conclusion for hospital blood is it is not selective. It’s not specific.  It’s certainly not forensic and it belongs nowhere inside a courtroom whatsoever.

We are all at least familiar with the way that a breath test machine works and an infrared breath test machine in particular, and that is based upon IR or infrared, and that is based upon Beer’s Law, the principal of Beer’s Law. You have an infrared light source, and the way that it is supposed to do the measurement according to Beer’s Law is as it goes through the sample chamber. If there is nothing interfering with it, when it hits the detector it should be at the same exact intensity.  So the arrow does not become smaller, it remains the same. As it is going through if there is nothing there to interfere with it the same amount of energy hits the detector. We all know that because you guys are a great breath-testing state. If you put in a molecule of interest, let’s say alcohol, inside that sample chamber it interferes with it and it shakes it up kind of, it’s asymmetric; and then the amount that it starts out is decreased because it is absorbed by that particular molecule as it hits the detector. That is how you know how much alcohol, what they say that the principle of alcohol breath testing is based upon.

No different in hospital blood testing.  In hospital blood testing it’s based upon again that uptake that’s involved. This is the spectra of ethanol. This is the wavelengths of, if you were to take it out over the entire spectrum as far as what it looks like. As we have probably been exposed to before, and I only use it to illustrate how bad hospital blood testing is, with an Intoxilyzer 5000 or most of the other models that are out there it is a three filter process or a five filter process, meaning that it is designed to take a look at certain wavelengths at certain points in time that may not be unique to alcohol.  In fact it is designed not to look for ones that are unique to alcohol as opposed to anything else that comes out there. The most important thing is that it is a three to five filter process. It is looking at three areas or five areas. Hospital blood testing looks at one. One. It is less specific. It is junkier because it only looks at that one wavelength. It only looks at one of the 340 wavelengths that are there.


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