Impairment Flashcards
Where is cannabis impairment an issue?
Driving, workplace testing
What is the main cannabinoid of interest when discussing impairment?
THC
What is the penalty for driving with THC blood level of 2 ng/mL - 5 ng/mL?
Maximum fine of $1,000.
What is the penalty for a first offense of driving with a blood [THC] of 5 ng/mL or more?
Minimum $1,000 fine.
What is the penalty for a second offense of driving with a blood [THC] of 5 ng/mL or more?
30 days imprisonment.
What is the penalty for a third offense of driving with a blood [THC] of 5 ng/mL or more?
120 days imprisonment.
What is the penalty for a first offense of driving with a blood [THC] of up to 2.5 ng/mL and greater than 0.05% BAC?
Min. $1,000 fine.
What is the penalty for a second offense of driving with a blood [THC] of up to 2.5 ng/mL and greater than 0.05% BAC?
30 days imprisonment.
What is the penalty for a first offense of driving with a blood [THC] of up to 2.5 ng/mL and greater than 0.05% BAC?
120 days imprisonment.
True or false: A per se limit is the limit at which all drivers below are not impaired and drivers above are impaired.
False.
Define impairment.
Decreased ability to perform a certain task.
Define intoxication.
Observable signs of drug use.
What types of studies can help investigate impairment?
Lab-based studies, studies of driving performance (on-road and simulated), epidemiology.
What type of situations are lab-based studies useful for?
For controlled environments and measurement of individual areas.
What type of situations are driving performance studies useful for?
Real world relevance.
Does cannabis cause impairment?
There is consensus within the scientific community that cannabis is associated with impairment, but the relationship is complicated.
List some cognitive and motor functions required for driving that cannabis has acute impairing effects on.
Decision-making, divided attention, motor coordination, reaction time.
What critical safe driving abilities has cannabis been shown to affect?
Slow reaction time, road tracking, cognitive performance, executive functions.
In terms of risk-taking, what have some driving simulator studies shown about driving after cannabis use?
Reduce speed, be less likely to pass, increase their following distance in an attempt to compensate for their perceived impairment.
What are risk-assessment questionnaires used for?
To measure an individual’s risk perception, which often correlates with actual behaviour.
How does perception of impairment differ between cannabis and alcohol users?
Cannabis users often overestimate their level of impairment while alcohol users tend to underestimate their level of impairment.
Why is it difficult to predict the extent to which a given amount of cannabis will have an impact on an individual?
Because the effects of cannabis reported across numerous studies have variable results.
What can variability of results be attributed to in terms of study design?
Dose, sensitivity of task or equipment, time after use.
What can variability of results be attributed to in terms of individuals?
Task skill, prior cannabis experience, usual dose and frequency of use, route of administration.
What have some recent studies shown regarding the impairing effects of THC:CBD ratios?
THC dominant and THC/CBD equivalent cannabis impair driving ability while CBD dominant did not have impairing effects.
Does impairment directly correlate with blood [THC]?
No.
Does peak impairment occur when THC concentration in blood is at or near peak levels?
No.
Can peak THC concentrations occur when low impairment is measured?
Yes.
Can high impairment be measured when [THC] is low?
Yes.
What might variability in blood [THC] and impairment arise from?
After smoking, THC concentrations drop rapidly while impairment may persist for hours, tolerance, chronic heavy users can have residual blood [THC], route of administration and affect blood [THC].
What does epidemiology say about cannabis and impairment?
Driving under the influence of cannabis was associated with a significantly increased risk of motor vehicle collisions compared with unimpaired driving.
What are 4 tools that are used to investigate impaired driving?
Standard field sobriety testing (SFST), Drug recognition evaluation (DRE), oral fluid screening equipment, blood testing for THC concentration.
What signs of cannabis use are police officers told to look out for?
Paranoia, body/eyelid tremors, drowsiness, increased appetite, uncoordinated, disorientation/confusion, dilated/unstable pupils, altered time/distance perception, drug residue in mouth.
What is the main tool which can be used at the roadside without any specialized equipment?
SFST
What three tests for SFST consist of?
Walk and turn, one-leg stand, examination of eye movements known as nystagmus.
What was the original purpose of the SFST?
Originally used to detect alcohol impairment but is now used to detect other drugs including cannabis.
Has research been conducted that shows a scientific basis for SFST?
Yes.
Outline the training required to use DRE testing.
2-week course on the science of drugs and the basics of how to perform all of the required tests followed by 1-week practical testing where you have to successfully ID what category of the drug a person is on.
What is DRE?
A detailed, diagnostic exam of persons arrested or suspected of drug-impaired driving or similar offenses. Based on the results of the drug evaluation, the DRE forms an expert opinion on a number of factors.
What factors does a DRE form an opinion on?
Is the person impaired and, if so, are they able to safely operate a vehicle. If impaired, is this impairment due to an injury or is it drug-related. If impairment is due to drugs, what category or combination of categories of drugs is the most likely source of the impairment.
What does section 52 of the constitution Act, 1982 establish?
The supremacy of the Constitution over all other laws in Canada.
Define section 52 of the Constitution Act, 1982.
The Constitution of Canada is the supreme law of Canada, and any law that is inconsistent with the provisions of the Constitution is, to the extent of the inconsistency, of no force or effect.
What information is required to establish that use of a drug results in impairment of driving skills and to justify a testing program to respond to such a hazard?
1) The drug can be demonstrated in lab studies to produce a dose-related impairment of skills associated with driving or with related psychomotor functions, 2) Concentrations of the drug and/or its metabolites in body fluids can be accurately and quantitatively measured and related to the degree of impairment produced, 3) Such impairment is confirmed by actual highway experience, 4) simple behavioural tests can indicate the presence of such impairment to the satisfaction of the courts and 5) A range of concentrations of the drug can be incorporated into laws relating to impaired driving as ipso facto evidence.
What have authors concluded about per se limits and impairment?
The use of per se limits as a means of identifying cannabis-impaired drivers should be reconsidered as there is a significant risk of unimpaired individuals being mistakenly identified as impaired under this approach.
What is another important question in addition to impairment issues related to per se limits?
Does a positive result from an oral screening test indicate a blood THC concentration greater than the legal limit?
How did ON prepare for research on fatal motor vehicle collisions following cannabis legalization?
Started to collect data before legalization so that any impact after 2018 could be monitored.
In the last study look at drug findings in FMVCs (2011), in how many deaths was THC positive?
27%
