Quiz #1: Biological Basis For Psychiatric Disorders And Psychopharmacology Flashcards
The brain matures from
Front to back
The Brain
- Trillions of cells that form highly specific structures and communication pathways.
- For the purpose of adaptation; changes occur in order to adapt to function
What are the characteristics that can be influential to understanding?
- Neuroplasticity
- Synaptic Pruning
- Many factors: chemical changes and balances that work hand in hand with CNS that come with any change of behavior or emotional state. Focus on that part of the anatomy.
Neuroplasticity
Ability of the brain to change structurally and functionally in response to input from the environment (How those cells communicate in order to respond)
Synaptic Pruning
- Refining by eliminating unneeded circuits and strengthening others to have a brain that accommodates. Includes Genetic Potential and Environmental Influence.
- Communicating with each other allows to create certain emotions and behaviors to adapt.
Structures of Brain and Function: Frontal Lobe
- Learning
- Abstracting
- Reasoning
- Inhibiting
Structure of Brain/Function: Parietal Lobe
-Someaesthetic and motor discrimination
Structure of the Brain/Function: Temporal Lobe
Discrimination of sounds; verbal and speech behavior
Structure of Brain/Function: Occipital Lobe
Visual discrimination and some aspects of visual memory
Structure of Brain/Function: Brainstem - Medulla
- Breathing
- BP
- Other vital functions
Structure of Brain/Function: Brainstem - reticular formation
- Arousal reactions
- Information screening
Structure of Brain/Function: Cerebellum
- Fine motor coordination
- Posture
- Balance
- Integration of emotional processes
Structure of Brain/Function: Corpus Callosum
-Communication between the brain’s right and left hemispheres
Structure of Brain/Function: Thalamus
- Major relay station for messages from all parts of the body
- Important in sensation of pain
Structure of Brain/Function: Pituitary
-Regulation of endocrine system
Structures that control cognitive, behavioral and emotional functions include
- Cerebral Cortex
- Basal Ganglia
- Hypothalamus
- Substantial Nigra
- Raphe nuclei
- Locus ceruleus
- Limbic System
The cerebral cortex is responsible for
- Decision making
- Higher-order thinking/abstract reasoning
The basal ganglia is responsible for
-Coordinates involuntary movements and muscle tone
The hypothalamus is responsible for
- Regulating pituitary hormones
- Temperature
- Behaviors such as eating, drinking and sex drive
The substantia nigra is responsible for
Making dopamine (a neurotransmitter involved in complex movements, thinking and emotions)
The raphe nuclei is responsible for
Making serotonin (a neurotransmitter involved in body’s response to stress)
The locus ceruleus is responsible for
Making norepinephrine (a neurotransmitter involved in the body’s response to stress)
The limbic system is responsible for
Regulating emotional behavior, memory and learning
Neurotransmitters
Chemical messengers responsible for impulse communication among neurons.
What is neurotransmission?
The process by which neurons communicate in the brain through electrical impulses and chemical messengers.
How does neurotransmission work?
- Like a key inserted into a lock, chemicals fit precisely into specific receptor cells.
- Receptor cells open or close doors (ion channels) into cells allowing interchange of chemicals or ions (i.e Na+, K+, Ca+)
- Depolarization changes the cell’s electrical charge
- Absence or excess can play major role in brain decrease and behavioral disorders.
- Single neurotransmitter can affect other brain chemicals and several different subtypes of receptor cells in different brain regions.
- Neurotransmitters can have different effects in different brain parts.
Explain the Physiology of Neurotransmitters
- Manufactured in the neurons
- Released from axon
- Moves into synapse
- Received by dendrite
- Exchange of ions causes impulse/reaction
- Receptor channel closes
- Neurotransmitter returns to presynaptic membrane (reuptake)
What are common neurotransmitters?
- Norepinephrine
- Dopamine
- Serotonin
Norepinephrine
- Plays a role in affective and anxiety disorders
- Fluctuates with sleep and wakefulness
Dopamine
- Involved in control of complex movements, motivation and cognition and in regulating emotional responses.
- Many drugs of abuse (cocaine, amphetamines) cause DA release
Dopamine is involved in what disorders
- Movement disorders seen in Parkinson’s disease
- Deficits seen in schizophrenia/psychosis (increase in dopamine with schizophrenia and psychosis)
Functions of Serotonin (5-HT)
- Fluctuates with sleep and wakefulness
- Plays a role in arousal and modulates activity of CNS, particularly in sleep onset.
- Plays a role in mood and probably in delusions, hallucinations and withdrawal symptoms of schizophrenia (decrease in serotonin with depression)
Other Neurotransmitters (Amino Acids) include
- Glutamate
- Gamma-aminobutyric acid (GABA)
Glutamate
- Implicated in Schizophrenia
- Receptors control the opening of ion channels that allow calcium (essential to neurotransmission) to pass into nerve cells, propagating neuronal electrical impulses
- This receptor is blocked by drugs that cause schizophrenic like symptoms.
Drugs that increase Gamma-aminobutyric acid (GABA) function such as benzodiazepines are used to
Treat anxiety and epilepsy and to induce sleep.
GABA and anxiety
There is a decrease in GABA with anxiety
Other Neurotransmitters: Endorphins, enkephalins, dynorphins, and endomorphins
The opiates morphine and heroine bind to these endogenous opioid receptors on presynaptic neurons, blocking the release of neurotransmitters and thus reducing pain.
Other neurotransmitters: Melatonin
- Is a monoamine, just like NE, DA, and 5-HT (serotonin)
- Induces pigment-lightening effects on skin cells and regulars reproductive and immune function.
Psychotherapy/Medications
- Both psychotherapy and medications may have a similar mechanism of action - neural plasticity
- That is the modification of a person’s brain structure - which then results in a change in behavior or symptoms.
- Many lack specificity and thus have undesired changes (side effects)
Circadian Rhythms
Resembles a network of internal clocks that coordinates events in the body to a 24-hour cycle.
Characteristics of Circadian Rhythms
- Body fluids and tissues function according to these rhythms
- Physical and mental abilities and moods may vary widely from one time of day to another
- To run on a 24-hour clock, circadian rhythms must have cues from external environment.
- Sunlight resets clock each day and synchronizes complex set of body rhythms (e.g hormonal messages to organs, thoughts and body functions)
Sleep
- 6-9 hours for usual adult sleep.
- Related to circadian rhythm, changes in light and darkness, and temperature changes.
Stages of Sleep
Cycles about 4-5 times in a good nights sleep
Stage 1: Falling asleep - drowsiness (5-10 minutes)
Stage 2: Light sleep - muscles tense and relax preparing to enter deep sleep (about 50% of the time)
Stage 3/4: Deep sleep (Delta sleep) -renews and rests the body
Stage 5: Rapid Eye Movement (REM) - increase in heart rate and erratic breathing; muscles tense and relax; dreaming
Human emotions and behaviors are partly governed by a variety of genes and their interplay with:
- Environment
- Personality
- Life experiences
Use of genetic psychiatry allows for
- Development of new medications
- Conduction of gene therapy
- Implementation of studies
What is Pharmacogenetics?
-Blends pharmacology with genomic capabilities.
Pharmacogenetics can allow
- Will eventually allow researchers to match DNA variants with individual responses to medical treatments.
- Will allow for design of custom drugs based on individual genetic profiles
- Targeting drugs to specific patients may allow the patient to avoid unwanted side effects.
Biological Assessment: Need to apply new information and apply holistic approach
- Symptoms of psychiatric versus neurologic or physical illness may overlap
- Complete history is needed
- Nurse should be able to perform basic physical examination
Screening or both undiagnosed physical and psychiatric disorders includes:
- Assessment of presenting symptoms
- Treatment selection
- Possible need for referral to specialist in another discipline
Biological Assessment: Healthcare History includes
- General Health care
- Treatments
- Brain Impairment
- Cancer
- Lung and cardiac problems
- Diabetes or other endocrine disturbances
- Menstrual, sexual and reproductive histories
Biological Assessment: Lifestyle assessment includes
- Diet
- Medications and other remedies
- Substance use
- Toxins
- Occupation
- Injuries, abuse
Nursing Assessment?
- Assess appearance, gait, coordination, bilateral strength and speech
- Document baseline symptoms so changes may be recognized
- Obtain patient’s permission to access other people and documents to help health care team gain information, including current medications
- Note inconsistencies in patient’s account, from others and health care records
- Be alert for history and indications of head trauma: accidents, fevers, surgery and seizures
Nursing Assessment: Symptoms
- Tremors and tics
- Headaches
- Blurred vision
- Dizziness
- Vomiting
- Motor weakness
- Disorientation
- Confusion
- Memory problems
Sedatives/Benzodiazepines: MOA
Binds to GABA receptors
Sedatives/Benzodiazepines: What do these drugs treat?
- Panic
- Anxiety
- Alcohol Withdrawal (Librium)
- Muscle spasm (Valium)
- Insomnia (Lunesta)
Benzodiazepines include
“PAM”
- Klonopin (clonazepam)
- Ativan (lorazepam)
- Valium (diazepam)
- Librium (chlordiazepoxide)
Sedatives include
- Ambien (Zolpidem)
- Lunesta - Insomnia or sleeping aids (Eszopiclone)
- Sonata (Zaleplon)
SSRI’s: MOA
Modulates/balances serotonin and sleep
SSRI’s are used to treat
Depression
SSRI’s include
- Lexapro
- Luvox
- Paxil (Luvox/Paxil are good for antianxiety and OCD)
- Prozac
- Trazodone
- Zoloft
- Celexa
Trazodone
- Prescribed for insomnia not narcotic
- SE: Sedation
SNRI’s Selective Norepinephrine Reuptake Inhibitors: MOA
Modulates both serotonin and NE
SNRI’s include
- Desipramine
- Imipramine
- Nortriptyline
- Amitryptline
MOAI’s include
Serotonin, Dopamine, Epi and NE
MOAI’s: MOA
Inhibits the action of MOA from breaking down these neurotransmitters
MOAI’s: Contraindications
- Tyramine containing foods such as aged cheese and wine; cough syrups.
- Leads to hypertensive crisis
MOAI Drugs include
- Marplan
- Nardil
- Parnate
Mood stabilizers
Balances out neurotransmitters so patient doesn’t have extremes of mood -> deep depression or high mania -> modulating reaction of receptor site to the neurotransmitter.
Lithium
- Gold standard for bipolar disorder.
- MOA is unknown.
-Therapeutic Window: 0.7-1.5
What is needed prior to lithium treatment?
- Renal clearance prior to initiation of treatment (BUN/Creat)
- Baseline TSH
- Normal Na and hydration (because lithium has a special affinity for sodium and fluid/water)
Therapeutic Window for Lithium is
0.7-1.5
What should you monitor for in patients taking lithium?
Monitor for toxicity:
- Tremor
- Polyuria, polydipsia
- Diarrhea
- Weight gain
- Vomiting
- CNS (sedation, cognitive impairment, impaired coordination, blurred vision)
- Dry mouth
Valproate (Depakote)
- MOA is unclear
- Treatment for bipolar disorder, bipolar mixed episode
Valproate (Depakote) Therapeutic Level
50-100
What do you need to monitor for in patients taking valproate?
- Mood
- Tremor
- Thrombocytopenia (CBC)
- Pancreatitis
- Hepatic failure (liver function tests)
Carbamazepine (Tegretol)
Treats bipolar disorder
Carbamazepine (Tegretol) MOA
Decreases Na+ channel firing
Carbamazepine (Tegretol) Therapeutic Level
4-12
Common side effects of carbamazepine (Tegretol)
- Anticholinergic
- Orthostatic hypotension
- Sedation
- Ataxia
- Rash (Stevens Johnsons Syndrome)
Lamictal
- Maintenance therapy for bipolar disorder.
- Also anti-seizure.
- Slow taper upwards
- Potential for Stevens Johnson Syndrome. (Report rash immediately)
What drugs are used to treat bipolar disorders?
- Lithium
- Valproate
- Carbamazepine
- Lamictal
Antipsychotic Medications: MOA
Block D2 and reduces dopamine transmission
(Overexcitement of the receptor of neurotransmitter creates the hallucinations and contact with reality. Dopamine, one of the NT and receptors with a special affinity to dopa. Overexcitement of the dopamine receptor -> hallucinations and delusions)
First Generation Antipsychotics: High Potency
- Haldol and Prolxin
- Increased Extrapyramidal symptoms and tardive dyskinesia
First Generation Antipsychotics: Low Potency
- Less Incidence of EPS
- Increased sedation
- Tachycardia
- Anticholinergic side effects (Thorazine)
Extrapyramidal Symptoms include
- Dystonia
- Akathesia - motor restlessness
- Parkinsonism
- Tardive Dyskinesia
Dystonia
Continuous spasm and muscle contraction of the neck, back, extremities, eyes, jaw and tongue
Parkinsonism Symptoms
- Rigidity
- Tremor
- Mask face
- Shuffling gait
- Stoop posture
Tardive Dyskinesia
Irregular jerky movement
Atypical Antipsychotics
Approved for Schizophrenia and Bipolar Disorder
Types of Atypical Antipsychotics include
-Abilifiy (Aripiprazole) “PINE”: -Clozaril (clozapine) *make sure to monitor blood work! -Seroquel (Quetiapine) -Zyprexa (Olanzapine) “DONE”: -Risperdal (Risperdone) -Geodon (Ziprasidone) -Inevga (Paliperidone)
