29. Anesthesiology Flashcards
A drug which, when applied “locally” in a concentration without toxic effects, reversibly blocks the conduction of nerve impulses (*both sensory and motor)
Local anesthetics
Action of local anesthetics: Blocks what?
Blocks sodium channels preventing depolarization (intracellular)
Injectable form of local anesthesia
Ionized form or Water soluble
Unionized free base form
Lipid soluble
Aka “acid dissociation constant”
Determines acidity of compound (ability to donate protons)
pKa
aka “power of hydrogen”
pH
pKa is aka
Acid dissociation constant
Lidocaine pKa = 7.8
pH = 7.8 (basic)
Ionized 💦:
Unionized:
Lidocaine pKa = 7.8
pH = 7.8 (basic)
Ionized 💦: 50%
Unionized: 50%
Lidocaine pKa = 7.8
pH = 4 (acidic)
Ionized 💦:
Unionized:
Lidocaine pKa = 7.8
pH = 4 (acidic)
Ionized 💦: >50%
Unionized: <50%
- kaya di nageeffect ung anes pag may infection
Lidocaine pKa = 7.8
pH = 10 (more basic)
Ionized 💦:
Unionized:
Lidocaine pKa = 7.8
pH = 10 (more basic)
Ionized 💦: <50%
Unionized: >50%
BQ: Order of Loss of Sensation
“PaT ToPS”
(“PaT ToPS”) Pain Temperature Touch Pressure Skeletal muscle tone
Increase dosage of anesthesia in bloodstream
Toxicity
Toxicity:
Toxicity:
✅Rapid induction of LA
✅Vessel deposition
✅Over dosage
Maximum number of carpules
7
Overdosage effects:
CNS-
Cardiac-
CNS: Anxiety
Heart: ⬇️fxn of heart > ⬇️blood to brain ➡️ Syncope
BQ: Most common medical emergency in the dental clinic
Syncope
Management of syncope
Trendelenburg position
H1 receptor : Bronchoconstriction and vasodilation
Examples of H1 blocker?
Diphenhydramine
Cetirizine
Loratadin
H2 - sTWOmach = ⬆️gastric sec = pain
Examples of H2 blockers?
Cemetidine
Ranitidine
Preservative of LA
- prevents contamination from microbes
Methylparaben
BQ: Antioxidant of vasoconstrictors (reducing agent)
Sodium bisulfites
Sa boards iniiba lang spelling ng “bisulfites”
Ester has highest incidence of LA allergic reaction because of
PABA (similar to methylparaben)
Bacteriostatic Drug that mimics PABA (⬆️allergy)
Sulfonamides
Most common vasoconstrictor
Epinephrine
BQ: Most impt function of vasoconstrictors?
Increase duration of effect of LA
BQ: What is the maximum dosage of vasoconstrictors for NORMAL Patients?
0.2mg or 200mcg
BQ: What is the max dosage of vasoconstrictors for CARDIOVASCULAR COMPROMISED patients?
0.04mg or 40mcg
Maximum number of cartridges given to CARDIOVASCULAR COMPROMISED patients
2 cartridges
BQ: What is the max number of LA carpule for AVERAGE pxs?
7 carpules
BQ: True or False. All local anesthetics are vasoCONSTRICTORS.
False!
[All LAs are vasoDILATORS]
#except: Cocaine (vasoconstrictor)
LA with vasoconstrictor or epinephrine is contraindicated to pxs with
Hyperthyroidism ❌
✅hypertension
BQ: 2% Lidocaine with 1:100,000 epi = 1.8ml
Mg of lidocaine?
20mg x 1.8ml = 36mg lidocaine
1: 100,000 Epi = ____mg
0.01mg
1:10,000 epi = ___mg
0.1mg
1:1000 epi = ___mg
1mg
mg of Epi in 1:100,000
{0.01mg x 1.8ml} = 0.018mg of epi
Generic name of Citanest
Prilocaine
“Weak vasodilator”
Mepivacaine
Amide local anes without vasoconstrictor
3% Mepivacaine
BQ: “longest acting anesthesia”
Bupivacaine
BQ: shortest acting AMIDE / amide with shortest duration of action
Mepivacaine 3%
BQ: LA contraindicated to pediatric patients
Bupivacaine
LA sometimes used for Toc douloureux
Bupivacaine
BQ: LA “rapidly metabolized by the body”
Articaine (metabolized by plasma and liver)
BQ: What amide local anes is combined to produce Topical anesthesia
Lidocaine + Prilocaine
BQ: What is the most common local anesthesia?
Lidocaine
BQ: Which amide LA is safe for children and patients with cardiovascular problems
Mepivacaine
BQ: Only LA that is a vasoconstrictor
Cocaine
Mepivacaine
1st LA
Cocaine
Synergist to catecholamines = ⬆️BP (not used anymore)
Cocaine
“1st synthetic LA”
Procaine
“Shortest acting LA”
Procaine
Most common topical anesthesia
Benzocaine
BQ: remember: majority of LA used today are:
Tertiary amines (amide)
Short needle = _mm
Short: 20mm
Long needles: _mm
Long : 32mm
Ultrashort = _mm
Ultrashort - <20mm
Most commonly fractured gauge of needle
30g
Most common site of needle fracture
Hub
Gauge used for high risk of positive aspiration (eg. APLASTIC ANEMIA)
25g
BQ: What needle is used in mandiblock in PEDIA
Child: 27g Short
[Adult: 27g Long]
BQ: What needle is used for intraligamentary injection?
30g ultrashort
BQ: What is the level of the needle when doing classic mandibular blocking in CHILDREN?
45 degrees - below occ plane
BQ: What is the angulation of the needle when doing classic mandiblock in ADULTS?
Parallel to occ plane
BQ: 1st IANB fails: what will you do next?
Inject HIGHER
Baka nagmigrate ung pterygomn space bec of bony deposition
Most common Complication assoc with PSAN block
Hematoma
“true asan block”
Infraorbital nerve block
BQ: Reference in infraorbital nerve block
1st PM
2nd option: distal of canine
BQ: Most common complication assoc with Infraorbital nerve block
Ecchymosis
Infraorbital nerve block includes what nerves
Asan ✅
Msan (sometimes)
BQ: Rx app of “nasopalatine duct cyst”
Heart shape rx app
Cyst located in the incisive foramen
Nasopalatine duct cyst
“Nerve of scarpa”
Nasopalatine nerve
“Anterior palatine nerve”
Greater palatine nerve
“Posterior palatine nerve”
Lesser palatine nerve
BQ: GPNB blocks:
A. Post 2/3 of hard palate
B. Post 2/3 of hard palate ON THE SIDE OF INJECTION
B!!! On the side of injection!
Why contralateral side in mandiblock?
To prevent BELL’S PALSY
Most common muscle involved in trismus
Medial pteygoid muscle
“True mandibular blocking”
Gow gates technique
- block V3 (nerve trunk)
“Closed mouth mandibular blocking”
Akinosi vazirani
Technique used for pxs with trismus or for pediatric pxs
Akinosi vazirani
Reference point of Akinosi vazirani
Mx area or occ plane
