Anesthetics Flashcards
Chloroprocaine
trade name
Nesacaine
Chloroprocaine
onset
6-12 mins
Chloroprocaine
duration of action
0.5-1 hr
Chloroprocaine
max dose w/o Epi
800mg
Chloroprocaine
max dose w/ Epi
100mg
Procaine
Trade name
Novocaine
Procaine
onset
2-5 mins
Procaine
duration of action
1 hr
Procaine
max dose w/o Epi
750 mg
Procaine
max dose w/ Epi
1000 mg
Lidocaine
trade name
Xylocaine
Lidocaine
onset
3-5 mins
Lidocaine
duration of action
1.5-2 hrs
Lidocaine
Max dose w/o Epi
300 mg
Lidocaine
max dose w/ Epi
500 mg
Mepivacaine
trade name
Carbocaine, polocaine
Mepivacaine
onset
3-5 mins
Mepivacaine
duration of action
0.75-1.5 hrs
Mepivacaine
max dose w/o Epi
300 mg
Mepivacaine
max dose w/ Epi
not available
Bupivacaine
trade name
Marcaine, sensorcaine
Bupivacaine
onset
5 mins
Bupivacaine
duration of action
2-4 hrs
Bupivacaine
max dose w/o Epi
175 mg
Bupivacaine
max dose w/ Epi
225 mg
Examples of esters (2)
metabolization?
Chloroprocaine, procaine
metabolized in blood by pseudocholinesterase
Examples of amides (3)
metabolization?
lidocaine, mepivacaine, bupivacaine
metabolized by liver
MOA of local anesthetics
anesthetic interferes with sodium and potassium currents in the nerve to inhibit depolarization and prevent signal transmission
order of how nerve function is affected
pain > temp > touch > proprioception
Why is epinephrine added to anesthetics?
causes vasoconstriction which decreases bleeding, shortens the onset of anesthesia, and prolongs effect by slowing the absorption
conversion of concentration from % to mg
(% x 10) (# of mL used)
ex: 5 cc of 0.5% lidocaine = (0.5 x 10)(5)= 25mg of lidocaine
examples of how a person can get systemic toxicity with local anesthetics (3)
inadvertent intra-arterial or IV injection
administration of excessive doses
rapid absorption from a highly vascular area
symptoms of systemic toxicity of a local anesthetic
sensory disturbance, tongue numbness, twitching, vertigo, slurred speech, convulsions, hypotension, decreased cardiac output, cardiac collapse
pts might have an allergic reaction to ____ in ___ local anesthetics
PABA
ester
Hallux/digital blocks
- used for procedures involving the hallux or other digits
- types: Mercado (2 point), ‘V’, ‘H’, ring, triangle block
- blocks adjacent proper plantar digital nerves and adjacent proper dorsal digital nerves
- used for procedures involving the hallux or other digits
- types: Mercado (2 point), ‘V’, ‘H’, ring, triangle block
- blocks adjacent proper plantar digital nerves and adjacent proper dorsal digital nerves
Hallux/digital blocks
Mayo (ring) block
- frequently used for bunion surgery
- provides anesthesia proximal to the surgical site to preserve surgical tissue planes
- targets: saphenous, deep peroneal, medial plantar, medial dorsal cutaneous nerves
- may need to administer more local anesthetic at the distal interspace
- frequently used for bunion surgery
- provides anesthesia proximal to the surgical site to preserve surgical tissue planes
- targets: saphenous, deep peroneal, medial plantar, medial dorsal cutaneous nerves
- may need to administer more local anesthetic at the distal interspace
Mayo (ring) block
Ankle block
- used for procedures distal to ankle
- targets: tibial, saphenous, deep peroneal, superficial peroneal & sural
- also in ring form (instead of targeting specific nerve sites)
- used for procedures distal to ankle
- targets: tibial, saphenous, deep peroneal, superficial peroneal & sural
- also in ring form (instead of targeting specific nerve sites)
Ankle block
Tibial nerve (popliteal) block
- used for TAL, gastroc recession, repain of Achilles tendon rupture, extensive clubfoot release
- targets tibial nerve right after it branches from the sciatic nerve
- used for TAL, gastroc recession, repain of Achilles tendon rupture, extensive clubfoot release
- targets tibial nerve right after it branches from the sciatic nerve
Tibial nerve (popliteal) block
How is a tibial nerve block administered?
adult vs pediatric
- adult pts should be prone with knee flexed 30 degrees, wheal administered 7 cm proximal to the popliteal crease and 1 cm lateral to the midline, between the tendons of semitendinosus and biceps femoris
- pediatric pts may be supine if assistance is available to lift leg
infiltration block
- injection of anesthetic directly at the procedure site
- most frequently used in biopsy or excision of a lesion
- injection of anesthetic directly at the procedure site
- most frequently used in biopsy or excision of a lesion
infiltration block
American society of Anesthetists Physical status classification (level 1-6)
1 - normal health pt
2 - pt with mild systemic disease
3 - pt with severe systemic disease
4 - pt with severe systemic ds that is a constant threat to life
5 - moribund pt who is not expected to survive w/o the operation
6 - declared brain-dead pt whose organs are being removed for donation
conscious sedation (commonly used med and dose)
drug-induced depression or consciousness, during which pts continue to respond to physical and verbal stimuli
goal of conscious sedation
relieve anxiety and relax pt w/o depressing consciousness to the point that the airway is compromised
MAC
(monitored anesthesia care)
similar to conscious sedation, but pts are more deeply sedated - they are not easily aroused, but still respond purposefully to repeated or painful stimulation
- able to administer local anesthetic at operative site w/o pt discomfort
- pt is comfortable, airway is maintained, vitals are continuously monitored
- short recovery time and reduced incidence of nausea
conscious sedation
commonly used med and dose
- IV sedation and an analegesic/amestic
2 mg IV midazolam and 2 mg IV morphine
MAC
commonly used med and dose
- 1-2 mg of IV midazolam, repeated as needed for sedation
- 30-80mg bolus of IV propofol for induction, then 25-100ug/kg/min for maintenance
- 25-100ug of IV fentanyl by titration for analgesia
general anesthetics
pt loses consciousness and ability to purposefully respond
5 components of general anesthetics
loss of consciousness analgesia amnesia muscle relaxation blunting of autonomic reflexes
phases of general anesthetics
induction - pt goes from awake to unconscious, need adequate airway and ventilation
maintenance - unconscious state is continued for duration of surgery
emergence - awakening of pt
general anesthetics
commonly used med and doses
- combination of IV and inhalational agents
induced with IV push of 2mg/kg propofol (150-200mg in most adults)
maintained with isoflurane or sevoflurane, administered by vaporizer
