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129 terms

CNS Depressants

CNS Depressants packet. Includes narcotic analgesics, anesthetics, sedative/hypnotics including barbiturates, benzodiazepines & phenothiazines which make up the anticonvulsants
Analgesics do what
Decrease perception of pain
Anesthetics do what
Decrease sensation
Analgesics are divided into what 2 classes
Opioid and Non-Opioids
Opioid category
1. Agonists
2. Antagonist
3. Agonist-antagonist
Non-Opioid category
1. Salicylates
3. Adjuncts
Definition for agonist
Binds to the receptor site and causes the expected response
Definition for antagonist
Binds to the receptor site and does not initiate the expected response (blocks the site)
Definition for agonist-antagonist
Binds to the sites and causes some of the expected response but partially blocks others|NOTE: this concept is also referred to as PARTIAL agonists or COMPETITIVE agonism
Opioids are aka
Opioids are a generic reference to
Morphine-like drugs/actions
Opioids aka Narcotics act on
Endorphin receptors to decrease ability to propagate pain impulses:
1. Mu
2. Kappa
3. Sigma
Endorphin receptor Mu
Most important- expected effects, and wants more
Endorphin receptor Kappa
(similar to Mu) strong sedation
Endorphin receptor Sigma
(for undesirable effects such as dysphoria, hallucinations, AMS) "bad trip"
General actions of Opioids
1. Analgesia
2. Respiratory depression
3. Constipation
4. Urinary retention
5. Cough suppression
6. Emesis
7. Increased ICP ( indirect thru co2 retention)
8. Euphoria/ dysphoria
9. Sedation
10. Miosis
11. Decreased Pre-load/afterload low BP
Narcotics to know
1. Morphine (prototype)
2. Meperidine (Demerol)
3. Hydromorphone (Dilaudid)
4. Hydrocodone (Vicodin)
5. Oxycodone (Percocet)
6. Propoxyphene (Darvon)
7. Fentanyl (Sublimaze)
Anidote for opioid narcotics
Naloxone (Narcan)
What do adjunct meds do
They're not actually analgesics.
They potentiate analgesics (enhance the effects of)|
Examples of adjunct meds
1. Benzodiazepines
2. Antihistamines
3. Caffeine
Opioid antagonist
Naloxone is the prototype ( only one)
nalaxone (Narcan)
1. It competes with opioid receptor sites to block effect of the narcotic
2. used to treat heroin and opioid overdoes
3. shorter half-life than the narcotic means the Narcan will wear off and narcotic will still be there and bind to receptors
titrate Narcan to effect means
to respiratory rate to at least 8.
don't slam it! just enough to get them breathing well (not too much,not too fast)
trade name for morphine sulfate
Duramorph, Astramorph
classification of morphine sulfate (Duramorph, Astramorph)
1. Narcotic analgesic
2. CNS depressant
mechanism of action for morphine sulfate (Duramorph, Astramorph)
1. binds to opiate receptor sites in CNS to block pain.
2. CNS depression (decreased HR, low BP, decreased LOC
Indications for morphine sulfate (Duramorph, Astramorph)
1. pain
2. chest pain of suspected AMI origin, Acute pulmonary edema
trade name for fentanyl
trade name for meperidine hydrocloride
trade name for hydromorphone
classification for fentanyl, meperidine hydrocloride, hydromorphone
1. CNS depressant
2. Narcotic analgesic
indication for fentanyl, meperidine hydrocloride, hydromorphone
pain management
classification for nalaxone (Narcan)
Narcotic antagonist
mechanism of action for nalaxone (Narcan)
reverses effects of certain narcotic and synthetic narcotic analgesics by competing with analgesic at opiate receptor site
indication for nalaxone (Narcan)
know or suspected narcotic overdose with respiratory rate <8 or decreased tidal volume
asprin (Bayer) aslo NSAID
what does NSAID represent
Non-Steroidal Anti-Inflammatory Drugs
what are 5 NSAIDs
1. acetaminophen (Tylenol)
2. ibuprofen (Motrin, Advil)
3. naproxen sodium (Naprosyn)- prescription med
4. naproxen sodium (Aleve)- OTC
5. ketorlac (Toradol) -ONLY DRUG BY IM OR IV (for emesis pt.)
Aspirin mechanism of action
Inhibits synthesis of cyclooxygenase (COX)
cyclooxygenase (COX) is the enzyme responsible for
synthesis of Prostaglandins and Thromboxane A2
desired aspirin effects
1. pain relief
2. decreased fever
3. decreased inflammation
undesirable aspirin effects
1. GI ulceration (increased GI acidity,decreased GI protection)
2. increased bleeding
3. decreased renal elimination
4. decreased uterine contractions during labor
acetaminophen (Tylenol) side effects differs from aspirin how
1. does not cause gastric ulceration
2. does not decrease platelet aggregation
3. no decreased renal flow
4. no decrease uterine contractions
acetaminophen (Tylenol) does this the same as aspirin
inhibits the synthesis of CNS prostaglandins
acetaminophen (Tylenol) also inhibits
leukocyte migration and release of lysosomes
ketorolac (Toradol) anti-inflammatory effects are
caused by decreased prostaglandin synthesis
ketorolac (Toradol) pain management
related to decreased inflammation
ketorolac (Toradol) also has
antipyretic effects which means "decreased fever"
how is ketorolac (Toradol) different from other NSAIDs
can be given IM or IV which is great for vomiting patients
ketorolac (Toradol) deters
"frequent flyers"
trade names for aspirin
1. acetylsalicylic acid
2. ASA
3. Bayer
classifications for aspirin (acetylsalicylic acid, ASA, Bayer)
1. antiplatelet
2. anticoagulant
4. antipyretic
5. analgesic
mechanism of action for aspirin (acetylsalicylic acid, ASA, Bayer)
1. blocks platelet aggregation
2. slows prostaglandin synthesis action which also impedes inflammation response
indication for aspirin (acetylsalicylic acid, ASA, Bayer)
chest pain because of antiplatelet
precautions with aspirin (acetylsalicylic acid, ASA, Bayer)
asthmatic patients (may increase viscosity of respiratory secretions and cause mucous plug formation)
acetaminophen (Tylenol) classification
1. analgesic
2. antipyretic
acetaminophen (Tylenol) mechanism of action
decreased prostaglandin synthesis
acetaminophen (Tylenol) indications
1. fever
2. pain
acetaminophen (Tylenol) contraindication
children < 3 years old should have children's tylenol
anesthetics means
loss of all sensation
usually with anesthetic you have a loss of
consciousness, decreased propagation of neural impulses
neuroleptanesthesia is also called
conscious sedation
what is neuroleptanesthesia used for
procedures that require the patient's cooperation such as joint reduction
neuroleptanesthesia is a combination of
neuroleptic/antipsychotic (diazepam, droperidol, ketamine) and narcotic analgesic (meperidine, morphine, fentanyl)
-usually a drug that does not cause a drop in BP
local anesthetics
1. exert their affect on area around injection
2. usually accompanied by epinephrine, lidocaine (Xylocaine), topical cocaine (i.e.drops)
general anesthetic gases
1. nitrous oxide (Nitronox)
2. halothane
3. ether
Intravenous General anesthetics
1. thiopental (Pentothal)- barbiturate
2. methohexital (Brevitol)- barbiturate
nitrous oxide (Nitronox) classification
1. analgesic gas mixture
2. CNS depressant
3. anesthetic
nitrous oxide (Nitronox) mechanism of action
depressing the CNS
nitrous oxide (Nitronox) indication
pain relief
produce anesthesia and hypnosis but no analgesia
barbiturates mechanism of action
unknown, but believed to act on RAS
ultra-short acting barbiturates
used for premedication for RSI
1. onset 20-60 seconds (immediately)
2. duration 5 minutes
why is the onset and duration ideal for RSI
if you're unable to intubate, at least the patient comeback and able to breath for themselves at 5 minutes
longer acting barbiturates
used for seizures, anxiety, and sedation
Benzodiazepines vs. barbiturates
barbiturates are more potent and more addictive than benzodiazepines
the only barbiturate
phenobarbital (Luminal)
phenobarbital (Luminal) classification
1. Barbiturate
2. sedative-hypnotic
3. CNS depressant
phenobarbital (Luminal) mechanism of action
1. inhibition of the RAS
2. increases seizure threshold
phenobarbital (Luminal) indication
1. seizure
2. status epilepticus
major group where anticonvulsant drugs live
decrease anxiety and inhibitions
hypnotics means to
induce sleep
classes of sedative-hypnotic drugs
1. barbiturates
2. benzodiazepines
3. alcohol
both Benzodiazepines and barbiturates promote
the effectiveness of GABA receptors in the CNS
Benzodiazepines promote
GABA receptors ONLY
barbiturates promote GABA and
at high doses stimulate GABA receptors
what is GABA
the chief CNS inhibitory neurotransmitter
Benzodiazepine mechanism of action
mediate anxiety and sedation in the cerebellum
Benzodiazepine receptors in basal ganglia and hippocampus
cause muscle relaxation and decreased memory and sensation
has high concentration of benzo receptors
5 Benzodiazepines
1. diazepam (Valium) pre-hospital
2. midazolam (Versed) pre-hospital
3. lorazepam (Ativan) hospital
4. triazolam (Halcion) home med
5. alprazolam (Xanax) home med
"non-benzo benzos"
1. zolpidem (Ambien)
2. buspirone (BusPar)
do the same as benzos (for going to sleep)
5 barbiturates
1. phenobarbital (Luminal)
2. amobarbital (Amytal)
3. pentobarbital (Nembutal)
4. secobarbital (Seconal)
NOTE: if pt. is on barbiturates, they're in bad shape mentally
other sedatives
1. etomidate (Amidate) most used in hospital
2. propofol (Diprivan)
3. ketamine (Ketalar) horse tranquilizer
4. droperidol (Inapsine) tranquilizer
5. haloperidol (Haldol) tranquilizer
6. cholorpromaZINE (ThoraZINE) tranquilizer causes dystonic reaction, effects reversed w/ Benedryl
seizures are caused by
hyperactive brain areas
seizure drug classes
multiple chemical classes of drugs are used to treat
Anticonvulsants do what
1. increase motor cortex threshold
2. decrease propagation of actions potentials
3. stabilize the cell membrane
-decrease Na,Ca influx (delay depolarization and prolong repolarization
-increase Cl influx (hyperpolarize membrane so it cannot depolarize again
1. phenobarbital (Luminal)
1. diazepam (Valium)
2. lorazepam (Ativan)
3. midazolam (Versed)
Anticonvulsants-Misc. Agents
1. phenytoin (Dilantin) increases seizure threshold, drip
2. valproic acid (Depakote) home med
3. carbamazepine (Tegretol) home med
4. acetylzolamide (Diamox) decreases altitude ICP
Anticonvulsants-Magnesium Sulfate
1. decreases striated muscle contractions
2. blocks peripheral neurotransmission by decreasing ACH at motor nerve terminals
3. used for seizures associated with pregnancy
4. side effects include respiratory depression, hypotension, and decreased muscle reflexes
classifications for diazepam (Valium), midazolam (Versed), lorazepam (Ativan)
1. CNS depressant
2. benzodiazepine
3. anticonvulsant
4. sedative/hypnotic/amnestic
5. skeletal muscle relaxant
general mechanism of action for diazepam (Valium), midazolam (Versed), lorazepam (Ativan)
1. suppresses seizure activity
2. relaxes skeletal muscles
3. induces amnesia by depressing the CNS
general indications for diazepam (Valium), midazolam (Versed), lorazepam (Ativan)
1. seizures
2. status epilepticus
3. pre medication for pacing
4. cardioversion
5. RSI
unique indication for midazolam (Versed)
"chemical restraint" or acute anxiety disorder
unique indication for lorazepam (Ativan)
alcohol withdrawals (so they don't seize)
classifications for etomidate (Amidate), propofol (Diprivan), and ketamine (Ketalar)
CNS depressant, anesthetic, sedative/hypnotic
mechanism of action for etomidate (Amidate), propofol (Diprivan), and ketamine (Ketalar)
produces analgesia and amnesia
indicaiton for etomidate (Amidate), propofol (Diprivan), and ketamine (Ketalar)
Rapid Sequence Intubation
Duramorph, Astramorph
acetlsalicylic acid, ASA, Bayer
nitrous oxide