Term
thiopental
(class, mechanism, advantage/disadvantage, indication, contraindication, adverse effects, pharmacokinetics) |
|
Definition
Class: general anesthetic, intravenous
Mechanism: enhance GABA(A) receptor activity; rapid onset, terminated by redistribution
Advantages: anti-seizure activity
Disadvantages: poor analgesia, little muscle relaxation
Indication: induction of anesthesia (rapid onset), neonates req. higher dose for induction
Contraindication: PORPHYRIA
Adverse effects: (decreased cerebral metabolism, decreased cerebral blood flow, decreased BP, depressed respiration)
Pharmacokinetics: CONTEXT-SENSTIVE HALF-LIFE, terminal half-life is substantially longer w/ continuous infusion |
|
|
Term
propofol
(class, mechanism, advantage/disadvantage, indication, adverse effects, pharmacokinetics) |
|
Definition
Class: intravenous general anesthetic
Mechanism: enhances GABA(A) receptor activity
Advantages: high degree of clearance (hepatic --> rapid recovery, less hangover than thiopental
Disadvantages: poor analgesia, slight muscle relaxation
Indication: induction or maintenance anesthesia
Adverse effects: (decreased cerebral metabolism, decreased cerebral blood flow, decreased BP, depressed respiration), PAIN AT INJECTION, ABUSE POTENTIAL (anesthesiology residents)'
Pharmacokinetics: redistribution plays are role in action duration and half-life |
|
|
Term
etomidate
(class, mechanism, advantage/disadvantage, indication, adverse effects) |
|
Definition
Class: intravenous general anesthetic
Mechanism: enhance GABA(A) receptor activity
Advantages: rapid onset, cardio stable (use for patients who have risks if hypotensive)
Disadvantage: poor analgesic
Indication: induction of anesthesia
Adverse effects: (decreased cerebral metabolism, decreased cerebral blood flow, depressed respiration), SIGNIFICANT NAUSEA/VOMITING, PROLONGED SUPPRESSION OF ADRENOCORTICAL STRESS RESPONSE (up to weeks post-operative) |
|
|
Term
ketamine
(class, mechanism, advantage/disadvantage, indication, adverse effects, drug interaction) |
|
Definition
Class: intravenous general anesthetic
Mechanism: blocks glutamate receptors
Advantages: increases BP, ANALGESIC, good for kids, amnesic dissociate state
Indication: alone for short procedures (maintenance), induction for longer procedures
Adverse effects: INCREASED cerebral blood flow, cataleptic state (muscle rigidity), emergence delirium (<16y/o usually), analog of PCP (hallucinogenic, abuse potential)
Drug interactions: potentiates affects of non-depolarizing muscle relaxants; w/ theophylline predisposes to seizures |
|
|
Term
halothane
(IUSM know the adverse effects and pharmacokinetics) |
|
Definition
Class: volatile general anesthetic
Advantage: bronchodilator, some skeletal muscle relaxation; VERY POTENT MAC 0.75%
Disadvantage: high blood/gas coefficient (slow induction), weak analgesic
Adverse effects: liver toxicity (due to metabolite), MALIGNANT HYPERTHERMIA (esp. this halogenated GA)
Pharmacokinetics: significant hepatic metabolism to trifluroacetylchloride (hepatotoxic)
Special: discontinued in US |
|
|
Term
enflurane
(IUSM know the adverse effects) |
|
Definition
Class: volatile general anesthetic
MAC 1.6%
Advantages: bronchodilator, significant skeletal muscle relaxation
Disadvantages: high blood/gas coefficient (slow induction)
Indication: induction (not much in US)
Adverse effect: SEIZURE ACTIVITY
Pharmacokinetics: 2-8% metabolized |
|
|
Term
isoflurane
(class, advantage/disadvantage, MAC, indication, contraindication, adverse effects, pharmacokinetics) |
|
Definition
Class: volatile general anesthetic
Advantage: low blood/gas coefficient, induction <10min, good muscle relaxant
Disadvantages: pungent odor (not used for induction b/c of this)
MAC 1.2%
Indication: maintenance of anesthesia
Contraindication: CHD
Adverse effects: DILATES CORONARY ARTERIES (CORONARY STEAL), malignant hyperthermia, general halogenated GAs
Pharmacokinetics: eliminated unchanged in exhalation (>99%) |
|
|
Term
| Adverse effects of halogenated volatile GAs |
|
Definition
| tachycardia, peripheral vasodilation, hypotension, concentration dependent depression of ventilation, dilates cerebral arteries w/ possible increase in intracranial pressure |
|
|
Term
sevoflurane
(class, advantage/disadvantage, MAC, indication, adverse effect, pharmacokinetic) |
|
Definition
Class: volatile general anesthetic
Advantage: low blood gas coefficient (0.65), rapid onset, rapid recovery, potent bronchodilator, direct relax of skeletal muscle, NO TACHYCARDIA
Disadvantage: expensive
MAC 2%
Indication: induction or maintenance of anesthesia; widely used for outpatient procedures and pediatrics
Adverse effects: PRODUCES NEPHROTOXIC COMPOUND A WITH RECIRCULATION, malignant hyperthermia, general halogenated GAs
Pharmacokinetics: 3% metabolized, organic fluoride as by-product |
|
|
Term
desflurane
(class, advantage/disadvantage, MAC, indication, adverse effects, pharmacokinetics) |
|
Definition
Class: volatile general anesthetic
Advatanges: LOWEST BLOOD/GAS COEFFICIENT (0.42), low fat solublility, very rapid onset, rapid changes and recovery (5-10min), bronchodilator, direct skeletal muscle relax
Disadvantages: not very potent, expensive
MAC 6%
Indication: outpatient surgeries, maintenance only of anesthesia
Adverse effects: COUGH/SALIVATION/BRONCHOSPASM when awaken, STRONG AIRWAY IRRITANT (not used for induction), produces CO with recirculation (so don't recirculate), malignant hyperthermia, general halogenated AEs
Pharmacokinetics: <1% metabolized |
|
|
Term
methoxyflurane
(IUSM know the adverse effects) |
|
Definition
Class: volatile general anesthetic
DETRIMENTAL TO KIDNEYS - 65% metabolized to FLUORIDE IONS that are nephrotoxic |
|
|
Term
nitrous oxide
(class, advantage/disadvantage, MAC, indication, contraindication, adverse effects, pharmacokinetics) |
|
Definition
Class: volatile general anesthetic
Advantages: insoluble, significant analgesia
Disadvantages: weak anesthetic and very low potency
MAC 105%
Indication: adjunct to other inhalation or intravenous anesthetic (NEVER ABOVE 80%)
Contraindication: PULMONARY HYPERTENSION
Adverse effects: BOWEL DISTENTION, PNEUMOTHORAX, INNER EAR PAIN, DIFFUSIONAL HYPOXIA (req. 100% post-operative), increased cerebral blood flow w/ potential increases in intracranial pressure
Pharmacokinetics: 99.9% eliminate unchanged in lungs |
|
|
Term
| order of nerves blocked for local anesthetics |
|
Definition
pain (A-delta), autonomic C-fibers
cold
warmth
touch
deep pressure
motor |
|
|
Term
| use-depedendent block of local anesthetics |
|
Definition
| the greater the rate of nerve stimulation the greater the ability of the LA to block the VG-gated sodium channel |
|
|
Term
| what determines time to onset of local anesthetics |
|
Definition
pka of drug
(pH of tissues determines drug access to intracellular compartment) |
|
|
Term
| what determines duration of local anesthetic |
|
Definition
(contact time with nerve) affected by:
drug absorption (site of injection, dosage, adjunct)
drug distribution/redistribution (blood flow, ppb status, adjunct)
drug elimination (ester hydrlosis or amide metabolism by liver) |
|
|
Term
| metabolism of ester LA vs. amide LA |
|
Definition
ester - plasma cholinesterase
amides - hepatic CYP450 system |
|
|
Term
| unique adverse effect of ester LAs |
|
Definition
| potential allergic reaction due to metabolite (para-amino benzoic acid) |
|
|
Term
| what determines the potency of a local anesthetic |
|
Definition
|
|
Term
| patient characteristics of importance in local anesthetics |
|
Definition
liver disease - don't use amides
low esterase activity - don't use esters
neonates - lower plasma proteins, higher sensitivity to drugs
pregnancy - drugs more effective (??why??)
patients w/ spinal cord disease - use in spine w/ caution, may be useful in fixed spinal cord injury |
|
|
Term
| uses of local anesthetics |
|
Definition
1. local and regional anesthesia (topical, infiltration, intravenous)
2. peripheral nerve block
3. central nerve block
4. treatment of acute labor pain
5. analgesia in operative or post-op period
6. management of chronic pain (where local anesthetic may have prolonged effect)
7. aid in diagnosis and management prior to neurolytic procedures |
|
|
Term
| major adverse effects of anesthetics |
|
Definition
1. CNS - stimulation (restlessness, tremor, convulsions), depression (drowsiness, sedation, respiratory failure)
2. CV - heart (dec. conduction/force of contraction/excitability), vascular smooth muscle relaxation (dec. BP)
3. Smooth muscle - decrease bowel and uterine contraction
4. hypersensitivity rxns - dermatitis, asthmatic attack
5. nausea - procaine 17%
6. methoglobinemia - prilocaine, benzocaine |
|
|
Term
| mechanism of action for local anesthetics |
|
Definition
block VG-sodium channels from opening
block generation of an AP at post-synaptic cell |
|
|
Term
lidocaine (anesthetic)
(class, features) |
|
Definition
Class: local anesthetic, amide type
most popular
doses producing CNS toxicity cause cardiovascular depression |
|
|
Term
etidocaine
(class, features) |
|
Definition
Class: local anesthetic, amide type
BLOCKS MOTOR AND SENSORY ACTIVITY EQUALLY |
|
|
Term
bupivacaine
(class, features) |
|
Definition
Class: local anesthetic, amide type
more cardiotoxic than lidocaine
long-acting
levo-bupivacaine = s-enantiomer |
|
|
Term
ropivacaine
(class, features) |
|
Definition
Class: local anesthetic, amide type
less cardiotoxic than bupivacaine
long-acting |
|
|
Term
prilocaine
(class, features) |
|
Definition
Class: local anesthetic, amide type
methoglobinemia assoc. |
|
|
Term
procaine
(class, features) |
|
Definition
Class: local anesthetic, ester type
slow onset, short duration
metabolized to para-amino benzoic acid - potential allergic rxn |
|
|
Term
|
Definition
Class: local anesthetic, ester type
blocks NE (catecholamine) uptake
vasoconstrictor
abuse potential
used primarily in upper respiratory tract surgeries |
|
|
Term
benzocaine
(class, features) |
|
Definition
Class: local anesthetic, ester type
low sobulility (low potency)
MC topical agent
methemobglobinemia assoc. |
|
|
Term
tetracaine
(class, features) |
|
Definition
Class: local anesthetic, ester type
slower metabolism/more systemic toxicity assoc. |
|
|
Term
| topical local anesthetics |
|
Definition
MC - benzocaine
cocaine - ear, nose, throat only
lidocaine
lidocaine/prilocaine mixture - for 5mm depth (bridge between topical and infiltrative) |
|
|
Term
| infiltrative local anesthetics |
|
Definition
intradermal or subq injection
procaine - short duration
lidocaine - intermediate duration
bupivacaine - long duration |
|
|
Term
| intravenous local anesthetics |
|
Definition
tourniquet-occluded limb (forearm and hand = MC)
lidocaine w/o epi is most frequent agent |
|
|
Term
| peripheral nerve block local anesthetics |
|
Definition
onset determined by: proximity, cocnetration, volume and ionization of drug to nerve
lidocaine and bupivacaine MC |
|
|
Term
| central neural block local anesthetics |
|
Definition
epidural or intrathecal
vasodilation from sympathetic blockade
BARICITY - determines direction of migration
lidocaine shorter than bupivacaine < tetracaine |
|
|
Term
|
Definition
| lidocaine, prilocaine, bupivacaine, ropivacaine |
|
|
Term
| spinal (intrathecal) agents |
|
Definition
| procaine, lidocaine, bupivacaine |
|
|
Term
succinylcholine
(class, mechanism, onset, duration, elimination, special notes) |
|
Definition
Class: neuromuscular blocker, depolarizing
Mechanism: binds nicotinic ACH receptors causing prolonged depolarization and paralysis; causes initial wave of fasciculation
Time to onset: 1-1.5 min
Duration: 5-8 minutes
Elimination: hydrolysis by plasma esterases
Cholinesterase inhibitor effects: early on intensify blockade, later reverse blockade
Phase I - endplate depolarized
Phase II - endplate partially repolarized |
|
|
Term
d-Tubocurarine
(class, mechanism, duration, elimination) |
|
Definition
Class: neuromuscular blocker, non-depolarizing, natural alkaloid
Mechanism: competitive antagonist at nicotinic receptor at NMJ; not orally active must be injected
Time to onset: 4-6min
Duration: 80-120min (long)
Elimination: renal elimination, liver clearance |
|
|
Term
|
Definition
Class: neuromuscular blocker, non-depolarizing
Mechanism: competitive antagonist at nicotinic receptor at NMJ, nor orally active must be injected
Duration: 30-60 (intermediate)
Elimination: Hoffman, hydrolysis by esterases |
|
|
Term
|
Definition
Class: neuromuscular blocker, non-depolarizing
Mechanism: competitive antagonist at nicotinic receptor at NMJ, nor orally active must be injected
Duration: 80-100min (long)
Elimination: renal elimination |
|
|
Term
|
Definition
Class: neuromuscular blocker, non-depolarizing
Mechanism: competitive antagonist at nicotinic receptor at NMJ, nor orally active must be injected
Duration: 30-60min (intermediate)
Elimination: liver metabolism |
|
|
Term
|
Definition
Class: neuromuscular blocker, non-depolarizing
Mechanism: competitive antagonist at nicotinic receptor at NMJ, nor orally active must be injected
Duration: 60-90min (intermediate)
Elimination: liver metabolism, renal elimination |
|
|
Term
| non-depolarizing neuromuscular blocker adverse effects |
|
Definition
GANGLION BLOCKADE: decreased BP (d-TC > pan > atra/veru)
HISTAMINE RELEASE: decreased BP, bronchospasms, increased secretions (d-TC > atra >> pan/roc/veru)
MUSCARINIC BLOCKADE: tachycardia (pan and veru) |
|
|
Term
| depolarizing neuromuscular blocker adverse effects |
|
Definition
fsciculations
myalgia
hyperkalemia --> cardiac arrhythmias (esp. burn pts and soft-tissue injuries in paraplegics)
prolonged paralysis with atypical peudocholinesterase activity
MALIGNANT HYPERTHERMIA |
|
|
Term
| uses of neuromuscular blocker |
|
Definition
| major: surgical paralysis (NO ANALGESIC EFFECTS) |
|
|
Term
| sequence of paralysis in neuromuscular blockers |
|
Definition
1. muscles of fine movement (fingers, eyes, jaw, larynx)
2. limbs
3. trunk
4. intercostal muscles
5. diaphragm - recovers first, breathing recovers first |
|
|
Term
baclofen
(class, mechanism, indication, adverse effects, pharmacokinetics) |
|
Definition
Class: skeletal muscle relaxant
Mechanism: GABA(A) receptor agonist, spinal cord action to prevent excitation to motor neurons presynpatically, maybe supraspinal CNS action
Indicatoin: spasticity asocc. w/ MS/spinal cord injury or disease; trigeminal neuralgia
Adverse effects: DROWSINESS, dizziness, lightheadedness, confusion, muscle weakness
Pharmacokinetics: oral and intrathecal admin, renal elimination |
|
|
Term
dantrolene
(class, mechanism, indication, adverse effects, pharmacokinetics) |
|
Definition
Class: skeletal muscle relaxant
Mechanism: inhibits calcium release from SR in muscles
Indication: malignant hyperthermia (reduce mortality from 80% to <10%)
Adverse effects: muscle weakness
Pharmacokinetics: oral or IV admin, hepatic metabolism |
|
|
