7/17/19 Impairment: It’s All in the Head THIS PRESENTATION MAY CONTAIN MATERIALS CREATED BY OTHERS. SUCH MATERIAL IS USED UNDER A CLAIM OF FAIR USE PURSUANT TO THE FAIR USE GUIDELINES IN FACE-TO-FACE INSTRUCTIONAL EDUCATION ACTIVITIES. ADDITIONAL USE OR DISTRIBUTION OF THAT MATERIAL IS PROHIBITED. Outline Discuss the Role of the Toxicologist • Answer common questions in regards • to lab testing results. • Understand Timelines of Impairment • Explain the importance of understanding limitations in the testimony of a forensic toxicologist. 1
7/17/19 Alcohol Blood Levels & Subjective Effects 0.08 0.075 0.073 0.073 0.07 0.07 0.07 0.07 0.069 0.067 0.065 0.065 0.06 0.06 0.06 0.06 0.058 0.05 0.05 0.05 0.045 0.04 0.04 0.03 0.02 0.01 Adapted from: Sewell RA et al. The Effects of Cannabis Compared with Alcohol on Driving. Am J Addict. 2009 0 0 15 30 45 60 75 90 105 120 Alcohol (mg/dL) Alcohol (effects) The Value of a Strong DRE Program ▰ “The DRE program is the most effective tool currently available to law enforcement officers for the documentation of behavior and impairment in drug-impaired drivers.” -2004 - National Toxicologists, DREs, and Prosecutors (National Safety Council -Alcohol, Drug, and Impairment Division – NSC-ADID) 2
7/17/19 What makes a good DUID case? Solid Solid Solid Solid Tox Officer DRE Prosecutor Support What makes a good DUID case? Tox Officer DRE Prosecutor Support 3
7/17/19 ROLE OF THE TOXICOLOGIST ▰ WHAT DOES A TOXICOLOGIST BRING TO COURT? ▰ TERMINOLOGY DIFFERENCE? ▰ TOLERANCE ▰ SPECIMEN CHOICES ▰ TESTIMONY LIMITS? F. TOXICOLOGISTS TYPICALLY TESTIFY TO: Analytical Joey Jones - RRQ Drugs Chain of Found Custody 4
7/17/19 What does the Toxicologist bring to court? Administrative Documents: • Original Case File • Lab Reports /Receiving Sheet • Internal Chain-of-Custody • CV’s, Permits Analytical Documentation • Raw Generated Analytical Data • Physical Evidence (Blood or Urine) • Validation Records REFERENCES FOR THERAPEUTIC CONCENTRATIONS BASELT – MOLINA – DISPOSITION HANDBOOK TIAFT WINEK’S DRUG OF TOXIC OF FORENSIC THERAPEUTIC BLOOD LEVEL DRUGS AND TOXICOLOGY INDEX (2005) DATA (2001) CHEMICALS IN FOR MEDICAL MAN EXAMINERS ▻ *IMPORTANT* CONTEXT IS KING! ▻ SINGLE DOSE vs. STEADY STATE? ▻ PLASMA/SERUM vs. WHOLE BLOOD? 5
7/17/19 Important Resource: Prescription Instructions ▰ FDA Package Insert (Diazepam) ▰ Warnings: ▻ When diazepam is used with a narcotic analgesic, the dosage of the narcotic should be reduced by at least one-third and administered in small increments. In some cases the use of a narcotic may not be necessary. ▻ As is true of most CNS-acting drugs, patients receiving diazepam should be cautioned against engaging in hazardous occupations requiring complete mental alertness, such as operating machinery or driving a motor vehicle. TOXICOLOGISTS CANNOT TESTIFY TO: IS THE DRIVER IMPAIRED? (ULTIMATE QUESTION) Joey Jones - RRQ WHAT DRUG SYMPTOMS WOULD BE EXPECTED IN THE INDIVIDUAL DEFENDANT? IS THE DOSE PRESCRIBED APPROPRIATE FOR THE DEFENDANT? 6
7/17/19 THEN WHAT CAN WE DO? The Pharmacology Farm SPECIAL TOPICS: TERMINOLOGY IMPAIRMENT INTOXICATION VISIBLE/INVISIBLE SIGNS 7
7/17/19 SPECIAL TOPICS: TERMINOLOGY METABOLISM HALF LIFE CLEARANCE 8
7/17/19 Source: Casarett & Doull, Chaps. 5 and 7, 1996 9
7/17/19 • THC concentrations fall to about 60% of their peak within 15 min after the end of smoking • To about 20% of their peak within 30 minutes after the end of smoking. Cannabinoid Distribution/Elimination Courtesy Marilyn Huestis, Borkenstein Drug Course, 2009 THC Blood Levels & Subjective Effects 180 Adapted from: Sewell RA et al. The Effects of Cannabis Compared with Alcohol on Driving. Am J Addict. 2009 160 140 120 100 80 60 40 20 0 0 15 30 45 60 75 90 105 120 THC (ng/mL) THC (effects) 10
7/17/19 Common Questions • Why were drugs not detected? • Possible explanation(s) • Drug ingestion was outside of the detection time frame (blood vs. urine) • Liability à Time for arrival and evaluation completion. 12:20 AM – Initial Drug Use (~250ng/mL) 1:00 AM – Blood {50ng/mL} 12 12 1 Traffic Stop: 11 11 1:30 AM – Blood {<10ng/mL} 10 10 2 DRE Evaluation 2:00 AM – Blood {<5ng/mL} Specimen Collection 3 9 2:40 AM None Detected 8 4 7 5 6 Key Point: Every Second Counts 11
7/17/19 THC Levels in Whole Blood – Smoked vs. Oral Journal of Analytical Toxicology, Vol. 28. September 2004 Relationship of Delta 9-Tetrahydrocannabinol Concentrations in Oral Fluid and Plasma after Controlled Administration of Smoked Cannabis. Marilyn Huestis, Edward Cone. Clinical Chemistry 55:12 2180–2189 (2009) Delta 9-Tetrahydrocannabinol (THC), 11-Hydroxy-THC, and 11-Nor-9-carboxy-THC Plasma Pharmacokinetics during and after Continuous High-Dose Oral THC. Eugene W. Schwilke, David M. Schwope, Erin L. Karschner, et. al. 12
7/17/19 Effects and Uses of Marijuana • SFST performance!!! • Absence of HGN & VGN • Increased HR • Increase BP “It is concluded that it is unsafe to operate a vehicle or other complex equipment while under the influence of cannabis, due to the increased risk of death or injury to the operator and the public.” “It is further concluded that due to rapid changes in blood THC concentrations over time, there is no minimum safe threshold blood concentration below which a driver can be considered to have been unaffected while driving following recent cannabis use. Consequently, there is no scientific basis for the adoption of THC per se laws for driving.” 13
7/17/19 Common Questions • Why were other drugs detected than what the subject stated they took? • Metabolism – all drugs are transformed in the body to facilitate their utilization or elimination. • *An important step that your toxicologist can assist you with over the phone. Morphine, Heroin or Codeine? ▰ Morphine can arise in the blood and urine through the administration of morphine itself or through the metabolism of heroin or codeine 14
7/17/19 Common Questions • Why were drugs not detected? • Possible explanation(s) • The subject didn’t take (or know what they took) the drug. What is the best sample? 15
7/17/19 What is the best sample? There is no clear correlation between urine drug concentrations and impairment. - Alcohol (good) - Urine is only indicative of prior use What is the best sample - Urine? “Urine is a specimen best suited to demonstrate prior drug use or exposure (e.g., preemployment or workplace testing) rather than impairment proximate to the time of driving. In a DUID context, a positive urine drug test result could reflect use some time distant from the actual driving and beyond the duration of effect, or impairment” 16
7/17/19 Then it has to be Blood Right? It is very difficult to draw (on the spot) a clear correlation between blood drug concentrations and impairment for many drugs. - Alcohol (good) - Drugs à Researchers cannot ethically administer the doses of drugs typically taken by regular users - Rare à one single drug on board - Many Drugs have different effects in the acute phase from the later / withdrawal phase. 17
7/17/19 What is the best sample - blood? “Blood and oral fluid are the preferred matrices for DUID investigations. Blood is preferred because drug and metabolite concentrations can be evaluated within the context of therapeutic, toxic or recreational use. Although in any given case, issues related to tolerance and individual sensitivity must be considered, reference concentrations in blood provide useful interpretive context. ” ▻ What does therapeutic mean to you? 18
7/17/19 What are some FACTS about your lab? • Your lab cannot test for every known drug • Each laboratory has its own policy for testing DUID cases. • Ex: DUID/FATAL/DRE • Some labs may screen samples for only common classes of drugs – excluding other, less common drugs. • Other labs may be more extensive. • Some labs have been neglected for decades… • Equipment & Personnel Conclusion • Get to know you lab and toxicologists • When you start seeing things they need to know. • Have them come to a DRE Cert, Recert, Etc. • Bullet proof the front end of the case (Officer Observations, Narrative) • Consider setting up a lab liaison. • See if the lab can supply you with “Scope” Cards • Understand the time frame issues with sample collection & preservation. Get the sample as quickly as possible • 19
7/17/19 TESTIMONY LIMITATIONS 20
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7/17/19 “ Toxicological analysis of a biological specimen is the final step in the process and provides a nexus for the officer’s observations.” - Farrell, Kerrigan, and Logan. Recommendations of Toxicological Investigation of Drug Impaired Driving. Journal of Forensic Sciences. 2007. 22
7/17/19 DRE Evaluation DUID Arresting Driving & Officer Case SFSTs Observations Toxicology Questions? Contact Information Joseph O. Jones, MS 13 Children’s Way, R2109 Little Rock, AR 72202 O: 501.364.2670 C: 302.345.8206 jojonestox@gmail.com @THEREALJOJONES 23
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