Objective 2.1 (1) Flashcards
An unpleasant sensory and emotional experience associated with actual or potential tissue damage
A personal and individual experience
Whatever the patient says it is
Exists when the patient says it exists
pain
Level of stimulus needed to produce the perception of pain
A measure of the physiological response of the nervous system-therefore similar for most people
pain threshold
The psychological element of pain
The amount of pain a person can endure without it interfering with normal function
Varies from person to person
Subjective response to pain, not a physiological function
Varies by attitude, personality, environment, culture, ethnicity
pain tolerance
sudden, usually subsides when treated (postop pain)
acute pain
chronic or long-term pain, recurring lasts 3-6 months, and more difficult to treat
persistent pain
Pain results from stimulation of sensory nerve fibres called nociceptors.
These receptors transmit pain signals from various body regions to the spinal cord and brain
nociception
pain originating in skeletal muscles, ligaments or joints
somatic pain
pain originating from internal organs or smooth muscles
visceral pain
Medications that relieve pain without causing loss of consciousness
Commonly referred to as “Painkillers”
analgesics
moderate to severe pain
opioid analgesics
drugs from other chemical categories that are added to the opioid regimen
adjuvant analgesic drugs
what is the WHO 3-step analgesic ladder?
Step 1: Nonopioids with or without adjuvant medications after the pain has been identified and assessed. If pain persists or increases, treatment moves to:
Step 2: Opioids with or without nonopioids and with or without adjuvants. If pain persists or increases, management then rises to:
Step 3: Opioids indicated for moderate to severe pain, administered with or without nonopioids or adjuvant medications
Synthetic drugs that bind to the opiate receptors to relieve pain
Classified as both mild and strong agonists
opioid drugs
codeine, hydrocodone
mild agonists
morphine, hydromorphone hydrochloride, oxycodone, meperidine, fentanyl, methadone
strong agonists
not recommended for long-term use because of the accumulation of a neurotoxic metabolite, normeperidine, which can cause seizures
meperidine
drug reaches a maximum analgesic effect.
opioid ceiling effect
Bind to an opioid pain receptor in the brain
Cause an analgesic response (reduction of pain sensation)
agonists
Bind to a pain receptor
Cause a weaker pain response than full agonists
Also called partial agonists or mixed agonists
agonists-antagonists
Reverse the effects of these drugs on pain receptors
Bind to a pain receptor and exert no response
Also known as competitive antagonists
antagonists
what are opioids used for?
Mainly used to alleviate moderate to severe pain
Often first line agents analgesic in immediate post operative setting
Often given with adjuvant analgesic drugs to assist primary drugs with pain relief Balanced anaesthesia
Cough centre suppression
Treatment of diarrhea
what are the contraindications of opioids?
Known drug allergy
Severe asthma
Use with extreme caution in patients with the following:
Respiratory insufficiency
Elevated intracranial pressure
Morbid obesity or sleep apnea
Paralytic ileus (bowel paralysis)
Pregnancy
what are the interactions of opioids?
Alcohol
Antihistamines
Barbiturates
Benzodiazepines
Promethazine
Monoamine oxidase inhibitors (MAOI’s)-resp depression, seizures, hypotension
Others
what are the adverse effects of opioids?
Central nervous system (CNS) depression
Leads to respiratory depression
Most serious adverse effect
Nausea, vomiting, constipation, biliary tract spasm
Urinary retention
Hypotension, palpitations, flushing
Itching, rash, wheal formation due to histamine release (more with morphine, less with merperidine)
Pinpoint pupils indicating a possible overdose
A common physiological result of chronic opioid treatment
State of adaptation
Result: larger dose is required to maintain the same level of analgesia
opioid tolerance
Physiological adaptation of the body to the presence of an opioid
physical dependance
a pattern of compulsive drug use characterized by a continued craving for an opioid and the need to use the opioid for effects other than pain relief
addiction
From the opium poppy
Drug prototype for all opioid drugs; Schedule I controlled substance
For severe pain, with high abuse potential
Oral, injectable and rectal forms
Extended-release form includes MS Contin,
Potentially toxic metabolites morphine 6 glucuronide. Accumulation likely to occur in those with kidney insufficiencies.
morphine sulphate
Natural opiate alkaloid (Schedule I) obtained from opium
Less effective
Ceiling effect
More commonly used as an antitussive drug
Gastrointestinal (GI) disturbance
codeine sulphate
Synthetic opioid (Schedule I) used to treat moderate to severe pain
Parenteral injections, transdermal patches (Duragesic Mat® ), sublingual effervescent tablet (Fentora®
fetanyl
Hydromorphone (Dilaudid® ): very potent opioid analgesic; Schedule I drug
1 mg of intravenous (IV) or intramuscular (IM) hydromorphone is equivalent to 7 mg of morphine.
dilaudid
Synthetic opioid analgesic (Schedule I)
Opioid of choice for detoxification treatment of opioid addicts in methadone maintenance programs
Renewed interest in the use of methadone for chronic (e.g., neuropathic) and cancer-related pain
Prolonged half-life (24-36hours) of the drug: cause of unintentional overdoses and deaths
Cardiac dysrhythmias
methadone hydrochloride
Pure opioid antagonist
Drug of choice for the complete or partial reversal of opioid-induced respiratory depression
Indicated in cases of suspected acute opioid overdose
Failure of the drug to significantly reverse the effects of the presumed opioid overdose indicates that the condition may not be related to opioid overdose.
naloxone hydrochloride
Analgesic and antipyretic effects
Little to no anti-inflammatory effects
Available over the counter (OTC) and in combination products with opioids
Mechanism of Action:
Similar to that of salicylates
Blocks pain impulses peripherally by inhibiting prostaglandin synthesis
Also lowers febrile body temp by acting on the hypothalamus
Indications: Mild to moderate pain, Fever, Inability to take aspirin products
Contraindications/Interactions
Should not be taken in the presence of following: Drug allergy, Liver dysfunction, Possible liver failure, G6PD deficiency
Dangerous interactions may occur if taken with alcohol or other drugs that are hepatotoxic.
nonopioid analgesics: acetaminophen
Related to the marigold family
Anti-inflammatory properties
Used to treat migraine headaches, menstrual cramps, inflammation, and fever
May cause GI distress, altered taste, muscle stiffness, joint pain
May interact with aspirin and other NSAIDs, as well as anticoagulantsincrease in bleeding
Contraindicated in those with allergies to ragweed marigolds and those undergoing surgery
feverfew
a state of rest when physical and consciousness levels decrease
sleep
hypnotic drugs affect different stages of the normal sleep pattern.
various sedative
prolonged use of these drugs may reduce the cumulative amount of REM sleep
REM interference
Discontinuing these drugs, can cause REM rebound, and client then has large amount of REM sleep, leading to frequent and vivid dreams
REM rebound
a hormone secreted by the pineal gland in the human brain
Is a NHP and a commonly used sleep aid
Helps regulate other hormones and maintains the body’s circadian rhythm
Often taken for insomnia, sleep difficulties associated with menopause, jet lag and to promote sleep in children with ADHD or autism spectrum disorder.
Adverse effects: daytime fatigue, drowsiness, headaches, dizziness.
Contraindications: pts on anticoagulants, immunosuppressants, antihyperglycemics or BCP. Not to be used in pts with depression, HTN, reduced liver function or seizure disorder
melatonin
Drugs that have an inhibitory effect on the central nervous system (CNS) to the degree that they reduce:
Nervousness
Excitability
Irritability
sedatives
Cause sleep
Have much more potent effect on CNS than sedatives have
A sedative can become a hypnotic if given in large enough doses
hypnotics
At low doses, calm the CNS without inducing sleep
At high doses, calm the CNS to the point of causing sleep
sedative-hypnotics
what are the 3 classifications of sedative-hypnotics?
barbiturates
benzodiazepines
non benzodiazepine sedatives
Formerly the most commonly prescribed sedative–hypnotic drugs
Nonbenzodiazepines currently more frequently prescribed
Benzo’s show favourable adverse effect profiles, efficacy, and safety when used therapeutically in the short term
benzodiazepines
clonazepam (Rivotril® ), diazepam (Valium® ), flurazepam hydrochloride (Dalmane® )
long acting benzodiazepines
alprazolam (Xanax® ), bromazepam (Lectopam® ), lorazepam (Ativan® ), temazepam (Restoril® )
intermediate acting benzos
midazolam hydrochloride, triazolam, zolpidem tartrate (Sublinox® )
short acting benzos
what are the indications of benzos?
Sedation
Sleep induction
Skeletal muscle relaxation
Agitation or anxiety relief
Anxiety-related depression
Treatment of acute seizure disorders, alcohol withdrawal (ie. Diazepam), Short-term therapy for insomnia
what are the AE of benzos?
Mild and infrequent
Headache
Drowsiness
Paradoxical excitement of nervousness
Dizziness
Cognitive impairment
Vertigo
Lethargy
Fall hazard for older adults
“Hangover” effect or daytime sleepiness
First clinically available benzodiazepine drug. It has varied uses, including treatment of anxiety, procedural sedation, anticonvulsant, and skeletal muscle relaxant following orthopedic injury or surgery.
Helps with treatment of alcohol withdrawal.
Pg 218
diazepam
Most commonly used preoperatively and for procedural sedation
Causes amnesia and anxiolysis (reduced anxiety) as well as sedation
Normally administered by IV in adults
Liquid oral dosage form is also available for children.
Pg. 218
midazolam
Intermediate-acting benzodiazepine
One of the metabolites of diazepam
Normally induces sleep within 20 to 40 minutes
Long onset of action, so it is recommended that patients take it about 1 hour prior to going to bed.
Still an effective hypnotic; however, it has been replaced by newer drugs.
temazepam
Short-acting benzodiazepinelike drug
Unique advantage of this drug stems from its very short half-life.
Short-term treatment of insomnia, 7 to 10 days.
zopiclone
Short-acting nonbenzodiazepine hypnotic
Lower incidence of daytime sleepiness compared with benzodiazepine hypnotics
Onset of action approximately 30 minutes
zolpidem tartrate
Used to relieve anxiety, stress, and restlessness and to promote sleep
May cause temporary yellow skin discoloration (extended, continued intake), scaly skin, and visual disturbances
Potential interactions with alcohol, barbiturates, and psychoactive drugs
Contraindicated in liver disease, alcoholism, other conditions
Patient should not operate heavy machinery during use.
kava
Used to relieve anxiety, restlessness, and sleep disorders
May cause CNS depression, hepatotoxicity, nausea, vomiting, anorexia, headache, restlessness, insomnia
Many interactions, including with CNS depressants, monoamine oxidase inhibitors (MAOIs), phenytoin, warfarin, and alcohol
Contraindicated in cardiac and liver disease
Patient should not operate heavy machinery during use.
valerian
First introduced in 1903; were the standard drugs for insomnia and sedation
Habit forming; low therapeutic index
Only a few commonly used today partly because of the safety and efficacy of benzodiazepines
Psychologically habit forming
Have a low therapeutic index (Ex. There is a narrow range where the drug is effective, above this can be rapidly toxic)
MOA: Are CNS depressants that act primarily on the brain stem in an area called the reticular formation
barbituates
what are the interactions with barbituates?
Additive effects: Alcohol, antihistamines, benzodiazepines, opioids, tranquilizers
Inhibited metabolism: MAOIs prolong the effects of barbiturates.
Increased metabolism: Reduces anticoagulant response, leading to possible clot formation
what are the AE of barbituates?
Body system/adverse effects
Cardiovascular: Vasodilation, hypotension (esp if given too rapidly)
CNS: Drowsiness, lethargy, vertigo
Respiratory: Respiratory depression, cough
Gastrointestinal: Nausea, vomiting, diarrhea, constipation
Hematological: Agranulocytosis, thrombocytopenia
Other: Hypersensitivity reactions, Stevens-Johnson syndrome
Prototypical barbiturate
Long-acting drug
Uses: prevention of generalized tonic-clonic seizures and feverinduced convulsions, as well as treatment of hyperbilirubinemia in neonates
Rarely used today as a sedative and is no longer recommended to be used as a hypnotic drug
phenobarbital
Nonprescription sleeping aids often contain antihistamines, which have CNS-depressant effect.
Doxylamine succinate (Unisom-2 ® ), diphenhydramine hydrochloride (Sleep-Eze® ), acetaminophen/diphenhydramine (Extra Strength Tylenol® Nighttime)
As with other CNS depressants, concurrent use of alcohol can cause respiratory depression or arrest.
OTC hypnotics
Act to relieve pain associated with skeletal muscle spasms
muscle relaxants
only one is Dantrolene
Act directly on skeletal muscle
Closely resemble GABA
direct acting muslce relaxants
what are the interactions with muscle relaxants?
Relief of painful musculoskeletal conditions (Muscle spasms, MS, CP)
Work best when used along with physical therapy
Only contraindication is a known drug allergy
what are the AE of muscle relaxants?
Extension of effects on CNS and skeletal muscles
Euphoria
Lightheadedness
Dizziness
Drowsiness
Fatigue
Confusion
Muscle weakness, others
