Local anesthesia two Flashcards
t/f: if local anesthesia enters into the circulatory system it will cease to provide the desired effect.
true
t/f: Most local anesthetics have vasodilatation effect
true
_____ is the most potent vasodilator
Procaine:
the increase of absorption into the blood may lead to _____ _____ ______
potential systemic overdose
the only local anesthetic with constrictor
effect
cocaine
______ leads to Inhibition of catecholamine re-uptake
cocaine
_____ _____ has a poorly absorbed result except for cocaine.
Oral route of local anesthetics
____ _____ leads to Rapid absorption to mucous membrane
topical route
____ ____ has greatest % of anesthetics because it is the largest tissue mass in the body.
skeletal muscle
what are the two routes of drug elimination?
metabolic and excretory
t/f: ALL local anesthetics cross blood-brain barrier, and placenta
true
_____ _____ ____ is Hydrolyzed in plasma by pseudocholinesterase into paraaminobenzoic acid (PABA) .
ester local anesthesia
_______ is related to Allergic reaction
PABA (paraaminobenzoic acid)
____ ____ is about 1/2800 people and may lead to potential for toxicity of ester local anesthesics
Atypical pseudocholinesterase
t/f: the liver is the Primary biotransformation site for Amide local anesthetics
true
for a ASA IV to V patient with liver dysfunction, heart failure ____ _____ ____ are a relative contraindication
Amide local anesthetics
Blue Baby Syndrome
• Inherited blood disorder
• Atypical hemoglobin
– Unable to deliver oxygen efficiently
– Primary metabolite of Prilocaine can be the cause – S/S of patient: • Easily tired • Bluish tint on lip or skin
Methemoglobinemia
t/f: Kidneys are primary excretory organ of local anes.
true
in _____:
– Procaine appears as PABA (90%)
– 10% cocaine found
urine
t/f: Local anesthesia readily cross blood-brain barrier
true
Pharmacological of local anestheisa action is CNS_______
depression
Signs of CNS toxicty:
- Initial clinical signs/symptoms of CNS toxicity are Excitatory!!
– Numbness of tongue and circumoral region (symptoms)
– Slurred speech, shivering, A/V disturbances, Disorientation, tremor.. (signs)
– Luckily, lidocaine don’t have these s/s but mild sedation or drowsines
2) Higher level of CNS toxicity –> Tonic-clonic convulsion
3) Further increase
– cessation of seizure activity–> respiratory depression —> reparatory arrest
the following are systemic actions of local anesthesia on the _____ ____.
- Direct action on myocardium
– Produce myocardial depression
– Therapeutic advantage
– Management of hyper-excitable myocardium
• Premature Ventricular Contraction (PVC)
• Ventricular tachycardia
cardiovascular system
t/f: LA (local anesthetics) have a direction action on peripheral vasculature.
true
t/f: Cocaine and Ropivacaine are vasoconstrictors
true
t/f: All other local anesthetics are vasodilators
true
t/f: Skeletal muscle are more sensitive to local irritant properties
true
t/f: Respiratory is generally unaffected unless near overdose
true
t/f: No documented cases in medical or dental literature (past 25 years) supporting the concept of amide anesthetics triggering malignant hyperthermia
true
- ↓ Perfusion to site of administration
- Slow the absorption of L.A. into Cardiovascular system
- Minimize the risk of systemic toxicity
- ↑Duration of action for L.A.
- ↓Hemorrhage
importance of vasoconstrictors
Epinephrine
Norepinephrine
Dopamine
are ______ catecholamines
natural catecholamines
Isoproterenol
Levonordefrin
are______ catecholamines
Synthetic catecholamines
Amphetamine, Ephedrine, Methamphetamine
are ____-_______
Non-catecholamines
What are the three modes of action?
Direct acting
Indirect acting
Mixed acting
t/f: All Cathecholamines work on adrenergic receptors with
direct acting
true
the following are actions of ______ adrenergic Recptors
- vasoconstriction
- increased perpherial resistance
- increased blood pressure
- mydriasis
- increased closure of internal sphincter of the bladder
Alpha 1
the following are actions of ______ adrenergic Recptors
- inhibition of norepinephrine release
- inhibition of insulin release
alpha 2
the following are actions of ______ adrenergic Recptors
- TACHYCARDIA
- increased lipolysis
- increased myocardial contractility
beta 1
the following are actions of ______ adrenergic Recptors
- vasodialtion
- slightly decreased peripheral resistance
- bronchodilation
- increased muscle and liver glycogenolysis
- relaxed uterine smooth muscle
beta two
______ = vasoconstriction
alpha 1
_______= post synaptic inhibitory
alpha 2
______=located at heart at intestine
beta 1
_____= Vasodilatation (found in the Bronchi, Vascular beds)
beta 2
______ is commonly referred to as ratio
Dilution
Concentration of 1:1000 means?
- 1gram (1000mg) of solute (drug) in 1000ml solution
So 1000mg / 1000ml = 1.0mg/ml of solution
______ is the most used vasoconstrictor
Epinephrine
____ ____ Sodium Bisulfite (antioxidant) is added to delay deterioration of epine.
Sodium Bisulfite (antioxidant) is added to delay deterioration
t/f: Shelf life of L.A. with Epi is ~ 18 months and Epi can be synthetic or obtained from adrenal medulla
true
____ _ is more sensitive to epinephrine
Beta 2
_______ is a Potent bronchiole smooth muscle dilator treat acute asthma
Epinephrine
t/f: Epinephrine plasma level does increase after “usual” intra oral injection despite of aspiration
true
Intravascular injection of 0.015mg can cause what?
Increase heart rate from 25 bpm to 75 bpm
Systolic blood pressure from 20mmHg to 70mmHg
BE AWARE OF REACHING STROKE LEVELS.
________ lacks significant B2 actions resulting in Intense vasoconstriction and Dramatic elevation of blood pressure.
Norepinephrine
What Most closely resemble norepinephrine?
Levonordefrin
When selecting a vasoconstrictor it is Dependent on the time needed for the procedure:
Without epi ~ ___ mine
With epi ~ __ mins
Without epi ~10 mins
With epi ~60 mins
t/f: Epinephrine produces rebound vasodilatory effect
ture
t/f: Norepinephrine produces cases of tissue necrosis and
slough.
Disadvantage outweigh its advantages, so it is not used.
true
What is the ASA classifcation: Normal healthy patient
asa1
What is the ASA classifcation: Mild systemic disease
asa2
What is the ASA classifcation:
Severe systemic disease that limits activity.
(Mild diabetes, controlled hypertension, obesity)
asa3
What is the ASA classifcation:
incapacitating disease that is a constant threat to life
CHF, Renal Failure
asa4
What is the ASA classifcation: Moribund patient not expected to survive 24 hours
(Ruptured aneurysm)
asa5
What is the ASA classifcation:
Brain-dead patient whose organs are being
harvested.
asa6
1) Blood pressure in excess of 200 mmHg systolic or 115 mmHg
2) Uncontrolled hyperthyroidism
3) Severe cardiovascular disease
a) Less than 6 months after myocardial infarction
b) Less than 6 months after cerebrovascular accident
c) Daily episodes of angina pectoris or unstable angina
d) Cardiac dysrhythmias despite appropriate therapy
e) Postcoronary artery bypass surgery (CABG), less than 6 months
4) Undergoing general anesthesia with halogenated agents
5) Patient receiving nonspecific B-blocker, MAOi, Tricyclic antidepressants
Patients in categories 1 to 3a through 3d are classified as ASA 4 risks and NOT normally considered candidates for elective or emergency dental
treatment in the office
Medical Status of the Patient Contraindications to Vasoconstrictor
t/f:
Key tips in delivering LA:
-Multiple aspirations
- Slow administration
-Minimum concentration of both
• Vasoconstrictor
• Local anesthetic
true
