Case 2 - Pain Flashcards
What aspects does CBT address?
- Cognitive sources of pain
- Emotional sources of pain
- Physiological sources of pain
What is the definition of addiction?
What are the most commonly abused drugs?
Compulsive engagement in rewarding stimuli, despite adverse consequences
Alcohol, opioids, and cocaine
Define these terms:
- Drug abuse
- Drug dependence (Physical)
- Drug dependence (psychological)
- Drug sensitisation
- Tolerance
What does detoxification do to tolerance?
- Substance used in a manner that doesnt conform to social norms
- Adaptive state associated with withdrawal syndome on cessation of the drug
- Acquiring and using the drug becomes a strong motivator of behaviour and use.
- Escalating effect of the drug due to repeated administration at a given dose
- Dminisheing effect of the drug due to repeated dosing.
Detox removes tolerance, so the drug level must be reduced to avoid overdose
What are the factors in DSM V which define a substance use disorder?
How many of these symptoms denote a severe substance use disorder?
- Tolerance
- Withdrawal symptoms
- Continuation despite negative personal consequences
- Using greater amounts, or using for a longer period than intended
- Persistent desire for the drug
- Are they stopping or reducing important activites?
6-7
- Which system in the brain is important for drug addiction?
- What is the effect of drugs on this area?
- Mesolimbic dopaminergic system
- Increases DA here
Where is the origin of the mesolimbic dopaminergic system?
Identify which number it is on the diagram?
Where does it project to?
Ventral tegmental area
Dashed line on number 2 pathway
Nucleus accumbens & prefrontal cortex
What does increased drug sensitisation lead to in:
- Nucleus accumbens
- increased DA outflow from the NA
What are the physiological effects of drug withdrawal on:
- Nucleus accumbens
- Reduction in DA outflow from NA – mediates rewarding effects
What is the correlation between the following receptor levels and drug intake?
- Low levels of D2
- High levels of D2
- Low levels of D2 – pleasure in drug naive individuals
- High levels of D2 associated with unpleasant feelings
What are the 3 types of opioid receptor?
What type of receptors are they?
- Mu
- Kappa
- Delta
G protein coupled receptors
Where are mu opioid receptors found?
What is the function of the mu opioid receptor?
What is the resulting effect on DA?
- Selectively expressed on inhibitory GABA interneurons in the VTA
- Hyperpolarise GABAergic neurons
- Leads to increased DA release, due to dis-inhibition of the neuron
What are the levels of NT and receptor at these times:
- Normal baseline
- During drug use (Acute intake)
- Mu Opioid receptor activation
- Chronic addiction
- Withdrawal
- Normal production of DA & Noradrenaline
- More GABA and more DA
- Suppression of GABA and increased DA
- MOR adaptation/sensitisation & reduced GABA suppression and less DA
- Increased GABA & Little DA - no reward
What are the risk factors of addiction?
- Genetic
- Environmental
- Familial or multi gene inheritance - DAergic genes which increases vulnerability
- Childhood trauma or events, stress, and availability of the drug - leads to the addiction
- What is the cause of sensation seeking which leads to addiciton?
- What is the cause of self-medication which leads to addiction?
- Positive reinforcement - Negative reinforcement. Drugs make them feel good - high drives drug use, feel horrible when not taking drug.
- Negative reinforcement - Negative reinforcement. Feel bad so take drugs to stop feeling bad, need the drug to feel better to deal with initial problem
What are the 3 methods of treating addiction?
- management of withdrawal
- harm reduction
- maintaining abstinence
What is an agonist?
What agonist is used for drug addiction?
How does it work?
What are the risks?
- A drug that has the same effect as receptors ligand
- Methodone
- Acts as straight substitute for heroin, allowing for easier withdrawal of heroin
- respiratory depression
What is a partial agonist?
What agonist is used for drug addiction?
How does it work?
What are the risks?
- A drug that acts like the ligand to the receptor, but does not have exactly the same effect
- Buprenorphine
- Not as strong in its effects as morphine, allows for weaning
- Less risk of respiratory depression but less pleasurable than full agonist
What is an antagonist?
What agonist is used for drug addiction?
How does it work?
What are the risks?
- Has the opposite effect to the drug/receptor ligand
- Naltrexone
- Blocks mu opioid receptor - reduced DAergic activity, reducing drug cravings
- Low adherence, but safest of all
What are the lifestyle and behaviour changes that can also be encouraged? What is involved?
- Motivational interviewing - target ambivalence
- Community reinforcement - Earn tokens/money with clean urine samples
- Relapse prevention - CBT, finding a healthier alternative etc.
- Where does the sciatic nerve originate?
- What does the sciatic nerve divide into?
- Where does the sciatic nerve divide into its 2 branches?
Identify:
- Sciatic nerve
- Common fibular nerve
- Tibial nerve
- L4-S3 from lumbar & saccral plexus
- Tibial nerve & Common fibular nerve
- Popliteal fossa