CNS, ANS Flashcards
1
Q
Adjunctive anaesthetic drugs
A
Drugs used in combination with anaesthetic drugs to control the adverse effects of anaesthetics or to help maintain the anaesthetic state in the patient
2
Q
Anaesthesia
A
Loss of the ability to feel pain, resulting from the administration of an anaesthetic drug or other medical intervention
3
Q
Anaesthetics
A
Drugs that depress the central nervous system (CNS) to produce diminution of consciousness, loss of responsiveness to sensory stimulation, or muscle relaxation
4
Q
Balanced Anaesthesia
A
The practice of using combination of drugs rather than a single drug to produce anaesthesia. A common combination is a mixture of sedative-hypnotic, an anti anxiety drug, an analgesic, an antiemetic, and an anticholinergic
5
Q
General Anaesthesia
A
A drug-induced state in which the CNS is altered to produce varying degrees of pain relief throughout the body as well as depression of consciousness, skeletal muscle relaxation, and diminished or absent reflexes
6
Q
General Anaesthetic
A
A drug that induces a state of anaesthesia. Its effects are global in that it involves the whole body, with loss of consciousness being one of those effects
7
Q
Local anaesthetics
A
Drugs that render a specific portion of the body insensitive to pain at the level of the peripheral nervous system, normally without affecting consciousness; also called regional anaesthetics
8
Q
Malignant Hyperthermia
A
A genetically linked major adverse reaction to general anaesthesia, characterized by a rapid rise in body temperature, as well as tachycardia, tachypnea, and sweating
9
Q
Minimum alveolar concentration
A
The minimal concentration of the gas in the lungs that is needed to provide anaesthesia in 50% of subjects
10
Q
Moderate sedation
A
A form of anaesthesia induced by combinations of parenteral benzodiazepines and an opiate; also called conscious sedation
11
Q
Overton-Meyer theory
A
A theory that describes the relationship between the lipid solubility of anaesthetic drugs and their potency
12
Q
Parenteral Anaesthetics
A
Any anaesthetic drugs that can be administered by injection via any route (IV, spinally, epidurally) as a local nerve block
13
Q
Topical Anaesthetics
A
A class of local anaesthetics consisting of solutions, ointments, gels, creams, powders, ophthalmic drops, and suppositories that are applied directly to the skin and mucous membranes
14
Q
Anxiolytic
A
A medication that relieves anxiety
15
Q
Barbiturates
A
A class of drugs that are chemical derivatives of barbituric acid. They can induce sedation and sleep
16
Q
Benzodiazepines
A
A chemical category of drugs most frequently prescribed as sedative-hypnotic and anxiolytic drugs; the most common group of psychotropic drugs currently prescribed to alleviate anxiety
17
Q
Gamma-aminobutyric acid (GABA)
A
An inhibitory neurotransmitter found in the brain that functions to inhibit nerve transmission in the CNS
18
Q
Hypnotics
A
Drugs that, when given at low to moderate doses, calm or sooth the CNS without inducing sleep but when given at high doses may cause sleep
19
Q
Non-rapid eye movement (Non-REM) sleep
A
One of the stages of the sleep cycle. It characteristically has four stages and precedes REM sleep. Most of a normal sleep cycle consists of non-REM sleep
20
Q
Rapid-eye movement (REM) sleep
A
One of the stages of the sleep cycle. Some of the characteristics of REM sleep are rapid movement of the eyes, vivid dreams, and irregular breathing
21
Q
REM interference
A
A drug-induced reduction of REM sleep time
22
Q
REM rebound
A
Excessive REM sleep following discontinuation of a sleep-altering drug
23
Q
Sedatives
A
Drugs that have an inhibitory effect on the CNS to the degree that they reduce nervousness, excitability, and irritability without causing sleep
24
Q
Sedative-hypnotics
A
Drugs that can act in the body either as sedatives or hypnotics
25
Sleep
A transient, reversible, and periodic state of rest in which there is a decrease in physical activity and consciousness
26
Sleep architecture
The structure of the elements involved in the sleep cycle, including normal and abnormal patterns of sleep
27
Tachyphylaxis
The rapid appearance of a progressive decrease in response to a drug after repetitive administration of the drug
28
Therapeutic index
The ratio between the toxic and therapeutic concentrations of a drug. If the index is low, the difference between the therapeutic and toxic drug concentrations is small, and use of the drug is more hazardous
29
Anticonvulsant
A substance or procedure that prevents or reduces the severity of epileptic or other convulsive seizures
30
Antiepileptic drug
A substance that prevents or reduces the severity of epilepsy and different types of epileptic seizures, not just convulsive seizures
31
Autoinduction
A metabolic process that occurs when a drug increases its own metabolism over time, leading to lower than expected drug concentrations
32
Convulsion
A type of seizure involving excessive stimulation of neurone in the brain and characterized by the spasmodic contraction of voluntary muscles
33
Epilepsy
General term for any of a group of neurological disorders characterized by recurrent episodes of convulsive seizures, sensory disturbances, abnormal behaviour, loss of consciousness, or any combination of these
34
International Classification of Seizures
The most extensively used system of classifying seizures, including the symptoms and characteristics of each type of seizure
35
Narrow therapeutic index (NTI) drugs
Drugs that are characterized by a narrow difference between their therapeutic and toxic doses
36
Primary or idiopathic epilepsy
Epilepsy that develops without an apparent cause. More than 50% of cases of epilepsy are of unknown origin
37
Secondary epilepsy
Epilepsy that has a distinct cause (trauma)
38
Seizure
Extensive stimulation of neurone in the brain leading to a sudden burst of abnormal neurone activity tat results in temporary changes in brain function
39
Status Epilepticus
A common seizure disorder characterized by generalized tonic-clonic convulsions that occur in succession
40
Tonic-clonic seizure
Formerly called grand map seizure, this type of epilepsy is characterized by a series of generalized movements of tonic (stiffening) and clinic (rapid, synchronized jerking) muscular contraction
41
Unclassified seizures
Seizures that are not described by any of the seizure classifications
42
Akinesia
Reduction or lack of psychomotor captivity of voluntary muscles
43
Anticholinergic drugs
Drugs that block or impede the activity of the neurotransmitter acetylcholine (ACh) at cholinergic receptors in the brain
44
Catechol ortho-methyltransferase (COMT) inhibitors
A class of indirect-acting dopaminergic drugs that work by inhibitions the enzymes COMT, which catalyzes the breakdown of dopamine
45
Chorea
A condition characterized by involuntary, purposeless, rapid motions such as flexing and extending the fingers, raising and lowering the shoulders, or grimacing
46
Dopaminergic drugs
Drugs used to replace the deficiency of dopamine at dopamine receptors in the nerve endings, especially in the brain when treating Parkinson's disease (can be direct- or indirect-acting or replacement drugs)
47
Dyskinesia
An impaired ability to execute voluntary movements
48
Dystonia
Impaired or distorted voluntary movement because of a disorder of muscle tone
49
Endogenous
Describes any substance produced by the body's own natural biochemistry (hormones, neurotransmitters)
50
Exogenous
Describes any substance produced out f the body that may be taken into the body (medication, food, or an environmental toxin)
51
On-off phenomenon
A phenomenon seen in patients taking levodopa long term, in which patients have periods of good control ("on" time) and those when they have bad control or breakthrough Parkinson's disease ("off" time)
52
Parkinson's Disease (PD)
A slowly progressive, degenerative neurological disorder characterized by resting remora, pill-rolling of the fingers, mask like facies, shuffling gait, forward flexion of the trunk, loss of postural reflexes, and muscle rigidity and weakness
53
Presynaptic drugs
Drugs that exert their antiparkinsonian effects before the nerve synapse
54
Wearing-off phenomenon
A gradual worsening of parkinsonian symptoms as a patient's medications begin to lose their effectiveness, despite maximal doses within a variety of medications
55
Adjunct Therapy
Combination drug therapy used when a patient's condition does not respond adequately to a single drug (monotherapy), or used when a given combination of medications is known to have therapeutic benefits over a single drug
56
Affective disorders
Emotional disorders that are characterized by changes in mood
57
Agoraphobia
Fear of leaving the familiar setting of home
58
Akathisia
Motor restlessness. A distressing experience of uncontrollable muscular movements that can occur as an adverse effect of many psychotropic medications
59
Antihistamine
Any substance capable of reducing the psychological and pharmacological effects of histamine, including a wide variety of drugs that block histamine receptors
60
Antipsychotic
A medication that counteracts or diminishes symptoms of psychosis; also called a neuroleptic
61
Anxiety
The unpleasant state of mind in which real or imagined dangers are anticipated or exaggerated
62
Anxiolytic
Capable of reducing anxiety; usually said of a medication
63
Benzodiazepine
A chemical category of drugs most frequently prescribed as sedative-hypnotic and anxiolytic drugs; the most common group of psychotropic drugs currently prescribed to alleviate anxiety
64
Biogenic amine hypothesis (BAH)
Theory suggesting that depression and mania result from alterations in neuronal and synaptic amine concentrations, primarily the catecholamines dopamine and norepinephrine, as well as the indolamines serotonin and histamine
65
Bipolar Disorder (BPD)
A major psychological disorder characterized by episodes of mania or hypomania, cycling with depression
66
Depression
An abnormal emotional state characterized by exaggerated feelings of sadness, melancholy, dejection, worthlessness, emptiness, and hopelessness that are inappropriate and out of proportion to reality
67
Dopamine Hypothesis
Theory that dopamine dysregulation in certain parts of the brain is one of the primary contributing factors to the development of psychotic disorders (psychoses)
68
Dysregulation hypothesis
Theory that depression and affective disorders are not simply the result of decreased or increased catecholamine and serotonin activity but failures of the regulation of these systems
69
Extrapyramidal Symptoms
Symptoms arising adjacent to the pyramidal portions of the brain
70
Gamma-aminobutyric acid (GABA)
An inhibitory amino acid in the brain that functions to inhibit nerve transmission in the central nervous system
71
Mania
A state characterized by an expansive emotional state; extreme excitement; excessive elation; hyperactivity; agitation; over talkativeness; flight of ideas; increased psychomotor activity; fleeting attention; and sometimes violent, destructive, and self-destructive behaviour
72
Monoamine oxidase inhibitor (MAOI)
Any of a heterogeneous group of drugs used primarily in the treatment of depression
73
Monotherapy
Pharmacological therapy involving a single medication for a specific condition
74
Neurotransmitter
Endogenous chemical in the body that serves to conduct nerve impulses between nerve cells
75
Psychosis
A syndrome consisting of a cluster of manifestations commonly associated with one or more mental health disorders
76
Psychotherapeutics
The therapy of emotional and mental health disorders, which may involve drug therapy (pharmacotherapy), a variety of counselling techniques, recreational therapy, and, in extreme cases, electroconvulsive therapy (ECT)
77
Psychotropic
Capable of affecting mental processes; usually said of a medication
78
Selective serotonin reuptake inhibitor (SSRI)
Any of a heterogeneous group of newer medications used to treat depression and certain mental health disorders and that work by selectively reducing postsynaptic reuptake of the neurotransmitter serotonin in the brain; also called serotonin selective reuptake inhibitor
79
Stigma
Widespread negative perceptions of and prejudice toward a specific group of people such as those with mental health disorders
80
Tardive dyskinesia
A serious drug adverse effect involving disordered body movements and muscle tension that is associated with antispychotic medications
81
Tricyclic antidepressants (TCAs)
A chemical class of antidepressant drugs with a distinctive three-ring segment in their chemical structure and that are used to block reuptake of the amine neurotransmitters serotonin and norepinephrine
82
Amphetamines
CNS stimulants that produce mood elevation or euphoria, increase mental alertness and capacity to work, decrease fatigue and drowsiness, and prolong wakefulness
83
Analeptics
CNS stimulants that have generalized effects on the brainstem and spinal cord, which, in turn, produce an increase in responsiveness to external stimuli and stimulate respiration
84
Anorexiants
Drugs used to control or suppress appetite that also stimulate the CNS
85
ADHD (Attention deficit hyperactivity disorder)
Syndrome affecting children, adolescents, and adults that involves difficulty maintaining concentration on a given task, hyperactive behaviour, or both
86
Cataplexy
A condition characterized by abrupt attacks of muscular weakness and hypotonia trigged by an emotional stimulus such as joy, laughter, anger, fear, or surprise
87
CNS stimulants
Drugs that stimulate specific areas of the brain or spinal cord
88
Migraine
A common type of recurring painful headache characterized by a pulsatile or throbbing quality, incapacitating pain, and photophobia
89
Narcolepsy
Syndrome characterized by sudden sleep attacks, cataplexy, sleep paralysis, and vial or auditory hallucinations at the onset of sleep
90
Serotonin receptor agonists
A new class of CNS stimulants used to treat migraines that work by stimulating 5-HT, receptors in the brain and are sometimes referred to as selective serotonin receptor agonists or triptans
91
Sympathomimetic drugs
CNS stimulants such as nor-adrenergic drugs whose actions resemble or mimic those of the sympathetic nervous system
92
Drug Therapy for PD (Parkinson's Disease)
```
Anticholinergic drugs (Benztropine)
Antihistamines (diphenhydramine)
Dopamine receptor agonists - direct acting (bromocriptine, levodopa, levodopa-carbidopa)
Indirect- acting dopamine recetor agonists (MAO-B [monomaine oxidase B] inhibitor or selegilline, COMT [catechol orthomethyltransferase] inhibit or entacapone, Misc. drugs (amantadine [Symmetrel])
```
93
Dopaminergic Therapy
Dopaminergic drugs are used to provide exogenous replacement of the lost dopamine or to enhance the function of the few neurons that are still producing their own dopamine
94
Levodopa Therapy
As PD progresses, it becomes more and more difficult to control with levodopa
Ultimately, levodopa no longer controls the PD, and patient is seriously debilitated (this generally occurs between 5-10 years after the start of levodopa therapy)
95
Dopaminergic Therapy: Replacement drugs (presynaptic)
These drugs work presynaptically to increase brain levels of dopamine
Levodopa is able to cross the BBB; then it is converted to dopamine. However, the large doses of levodopa needed to get dopamine to the brain also cause adverse effects
96
Dopaminergic Therapy: Replacement drugs (presynaptic)
Carbidopa is given with levodopa to prevent levodopa breakdown in the periphery
As a result, more levodopa crosses the BBB, where it can be converted to dopamine
97
Dopaminergic Therapy: Indirect acting (amantadine [Symmetrel])
Causes release of dopamine from the storage sites at the end of nerve cells that are still intact
Blocks the reuptake of dopamine into the nerve endings, allowing more to accumulate both centrally and peripherally
Does not stimulate dopamine receptors directly
98
Anticholinergic Therapy
Anticholinergics block the effects of ACh
They are used to treat muscle tremors and muscle rigidity associated with PD, two symptoms caused by excessive cholinergic activity
They do not relieve bradykinesia (extremely slow movements)
99
Anticholinergic Therapy
ACh accumulates because of the imbalance of dopamine
As a result, overstimulation of the cholinergic excitatory pathways occurs (muscle tremors and muscle rigidity; Cogwheel rigidity; Pill-rolling movement of fingers and head bobbing while at rest)
100
Dopaminergic Therapy: Indirect acting (COMT inhibitors)
Inhibit COMT; the enzyme responsible for the breakdown of levodopa, the dopamine precursor
101
Dopaminergic Therapy: Indications
Dopaminergic drugs are used to increase dopamine levels in the brain and to reduce the severity of PD symptoms
Amantadine (Symmetrel) also have antiviral effects
102
Anticholinergic Drugs Used for PD
Benztropine mesylate
Trihexyphenidyl (Trihexyphen)
Procyclidine hydrochloride
103
Anticholinergic Therapy: Indications
Used in the treatment of PD to cause smooth muscle relaxation, resulting in reduced muscle rigidity and akinesia
Also used to treat drug-induced extrapyramidal reactions to certain antipsychotic drugs
104
Selegiline: Indications
Used in combination with levodopa or levodopa-carbidopa
Used as an adjunctive when a patient's response to levodopa is fluctuating
Allows the dose of levodopa to be decreased; delays the development of unresponsiveness to levodopa therapy
The addition of selegiline commonly results in improvement in functional ability and decreased severity of symptoms
Pophylactic selegiline may delay the development of serious debilitating PD for 9-18 years
105
Anticholinergic Therapy: Adverse Effects
```
Drowsiness, confusion, disorientation
Constipation, N/V
Urinary retention, pain on urination
Blurred vision, dilated pupils, photophobia, dry skin
Decreased salivation, dry mouth
```
106
Selegiline: Adverse Effects
Usually mild and include: N, lightheadedness, dizziness, abdominal pain, insomnia, confusion, dry mouth
Doses higher than 10mg/day may cause more severe adverse effects, such as hypertensive crisis
107
Selective MAOI Therapy: Selgiline
MAOIs break down catecholamines in the CNS, primarily the brain
Selegiline is a newer, potent, irreversible MAOI that selectively inhibits MAO-B
If 10 mg or less is used, it does not elicit the "cheese effect" tyramine-containing foods of the nonselective MAOIs used to treat depression
Selegiline causes an increase in the levels of dopaminergic stimulation in the CNS
108
Antiparkinsonian Drugs: Nursing Implications
Perform a thorough assessment, nursing history, and medication history
Include questions about the patients: CNS; Psychological emotional status
Assess for S&S of PD: mask-like expression; speech problems; dysphagia; rigidity of arms, legs, neck
109
Antiparkinsonian Drugs: Nursing Implications
Provide patient education regarding PD and the medication therapy
Inform patient not to take other medications with PD drugs unless he or she checks with physician
When starting dopaminergic drugs, assist patient with walking because dizziness may occur
Oral doses should be given to minimize GI upset
Encourage patient to force fluids to at least 2000 mL/day (unless contraindicated)
110
Antiparkinsonian Drugs: Nursing Implications
Monitor for response to drug therapy:
- Improved sense of well-being and mental status
- Increased appetite
111
Antiparkinsonian Drugs: Nursing Implications
Pyridoxine (VB6) in doses greater than 10 mg will reverse the effects of levodopa
Teach patient to avoid foods high in VB6
Taking levodopa with MAOIs may result in hypertensive crisis
Patients should be told not to discontinue antiparkinsonian drugs suddenly
Teach patients about what therapeutic and adverse effects to expect with antiparkinsonian drug therapy
112
Antiparkinsonian Drugs: Nursing Implications
Levodopa preparations may darken the patient's urine and sweat
Therapeutic effects of COMT inhibitors may be noticed within a few days; it may take weeks with other drugs
Review the concept of "drug holidays" with patients using levodopa long term
113
Antiepileptic Drugs
Antiepileptic drugs (AEDs) are also known as anticonvulsants
Goals of drug therapy include: to control or prevent seizures while maintaining a reasonable QOL; to minimize adverse effects and drug-induced toxicity
AED therapy is usually lifelong
A combination of drugs may be used
Single-drug therapy is tried before two-drug or multiple-drug therapy is implemented
Serum drug concentrations must be measured
114
AED: Mechanism of Action
AED Therapy must:
- Prevent generation and spread of excessive electrical discharge from abnormally functioning nerve cells
- Protect surrounding normal cells
Exact mechanism of action is not known
AEDs are thought to alter the movement of Na+, K+, and Ca- ions across nerve cells in the brain
- Reduce nerve's ability to be stimulated
- Suppress transmission of impulses from one nerve to the next
- Decrease the speed of nerve impulse conduction within a neuron
115
AED: Mechanism of Action
Primary pharmacological effects of AED
- Increase threshold of activity in the brain motor activity
- Act to depress or limit the spread of seizure discharge from its origin
- They can decrease the speed of nerve impulse conduction within a given neuron
