VASOCONSTRICTORS Flashcards
are an integral and necessary part of most local anesthetic solutions used in dentistry
VASOCONSTRICTORS
drugs that contract the smooth muscle in blood vessels, which causes the vessels to constrict
VASOCONSTRICTORS
VASOCONSTRICTORS
by constricting blood vessels, it decreases _____ (perfusion) to the site of drug administration
o local anesthetic stays within area of administration due to
constriction of blood vessels
blood flow
VASOCONSTRICTORS
absorption of the local anesthetic into the cardiovascular system
is ____, resulting in lower anesthetic blood levels
slowed
VASOCONSTRICTORS
local anesthetics blood levels are ______, thereby decreasing
the risk of the local anesthetic toxicity
lowered
more local anesthetics enter into the nerve, where it remains for
longer periods, thereby increasing the duration of action of most local anesthetics
VASOCONSTRICTORS
it decreases bleeding at the site of administration, therefore,
they are useful when increased bleeding is anticipated
VASOCONSTRICTORS
→ an increase rate of absorption of the local anesthetics into the cardiovascular system, which in turn removes it from the injection site (redistribution)
o effectiveness of local anesthesia will not be as felt due to
widening of blood vessels
o there is a tendency to place more local anesthetic
VASODILATORS
higher plasma levels of the local anesthetic, with an attendant increase in the risk of local anesthetic toxicity (overdose)
VASODILATORS
decrease in both the depth and duration of anesthesia because the local anesthetic diffuses away from the injection site more rapidly
VASODILATORS
increase bleeding at the site of treatment as a result of increased perfusion
VASODILATORS
classification of sympathomimetic drugs by chemical structure is related to the presence or absence of _____
catechol nucleus
is ortho dihydroxybenzene
A. catechol
B. vasoconstrictors
A
are either catecholamines or
non-catecholamines
A. catechol
B. vasoconstrictors
B
vasoconstrictors that do not possess OH group in the third or fourth position of the aromatic molecule are not catechols but are ____ because they have an NH2 group attached to the ____ side chain
amines, aliphatic
chemical structure of a vasoconstrictor includes:
Catechol
Catecholamine
Non-Catecholamine
T/F
All vasoconstrictors are amines but not all are catechol.
T
there are (3) categories of sympathomimetic amines:
Direct-Acting
Indirect Acting
Mixed Acting or Combination
attaching or directly stimulating adrenergic receptors
A. Direct-Acting
B. Indirect Acting
C. Mixed Acting or Combination
A
acts by releasing norepinephrine from adrenergic nerve terminals
A. Direct-Acting
B. Indirect Acting
C. Mixed Acting or Combination
B
both direct and indirect actions
A. Direct-Acting
B. Indirect Acting
C. Mixed Acting or Combination
C
found in most tissues of the body
ADRENERGIC RECEPTORS
these types of receptors can be found in surfaces of cells that
get activated when they bind to a type of neurotransmitter such
as catecholamines
ADRENERGIC RECEPTORS
ADRENERGIC RECEPTORS
has (2) major categories:
Alpha, Beta
produces excitation of catecholamines
A. Alpha
B. Beta
A
vasoconstriction
A. Alpha
B. Beta
A
produces inhibition of catecholamines
A. Alpha
B. Beta
B
vasodilation
A. Alpha
B. Beta
B
excitatory
A. A1
B. A2
C. B1
D. B2
A
postsynaptic
A. A1
B. A2
C. B1
D. B2
E. Both A and b
F. Both C and D
E
inhibitory
A. A1
B. A2
C. B1
D. B2
B
heart and small intestine
A. A1
B. A2
C. B1
D. B2
E. Both A and b
F. Both C and D
C
responsible for cardiac stimulation & lipolysis
A. A1
B. A2
C. B1
D. B2
E. Both A and b
F. Both C and D
C
bronchi, vascular beds and uterus
A. A1
B. A2
C. B1
D. B2
E. Both A and b
F. Both C and D
D
produce bronchodilation & vasodilation
A. A1
B. A2
C. B1
D. B2
E. Both A and b
F. Both C and D
D
Maximum doses of vasoconstrictors are presented in ____ or more commonly today as ____ (μg).
milligrams, micrograms
Maximum doses of vasoconstrictors are presented in ____ or more commonly today as ____ (μg).
milligrams, micrograms
elevation of epinephrine plasma levels is linearly ____-dependent and persist from several minutes to half an hour
dose
associated with moderate increase in cardiac output and stroke volume, blood pressure and heart rate
EPINEPHRINE
in patients with pre-existing cardiovascular or thyroid disease, the side effects of absorbed ___ must be weighed against those of elevated local anesthetic blood vessels
epinephrine
T/ F
IV administration of 0.015 mg of epinephrine with lidocaine results in increase in heart rate ranging from 25-70 beats per minute with elevations in the systolic blood from 20-70 mm HG
T
occasionally rhythm disturbances may also be observed along with premature ventricular contractions (PVCS)
EPINEPHRINE
most useful and represents the best example of a drug mimicking the activity of sympathetic discharge
EPINEPHRINE
proprietary name of EPINEPHRINE
adrenalin
EPINEPHRINE
as the acid salt, it is highly ___ in water
soluble
In EPINEPHRINE this is added to delay deterioration
sodium bisulfite
shelf life of a cartridge with vasoconstrictor is shorter (18
months) than without a vasoconstrictor (36 months)
EPINEPHRINE
MODE OF ACTION
→ acts directly on both A and B adrenergic receptors (B effects predominate)
EPINEPHRINE
SYSTEMIC ACTION OF EPINEPHRINE
MYOCARDIUM
PACEMAKER CELLS
CORONARY ARTERIES
BLOOD PRESSURE
CARDIOVASCULAR DYNAMICS
VASCULATURE
HEMOSTASIS
RESPIRATORY SYSTEM
METABOLISM
SYSTEMIC ACTION OF EPINEPHRINE
MYOCARDIUM
PACEMAKER CELLS
CORONARY ARTERIES
BLOOD PRESSURE
CARDIOVASCULAR DYNAMICS
VASCULATURE
HEMOSTASIS
RESPIRATORY SYSTEM
METABOLISM
epinephrine-containing local anesthetic solutions are used via infiltration into surgical sites to prevent or to minimize hemorrhage during surgical procedures
HEMOSTASIS
T/ F
1:50,000 dilution of epinephrine is more effective than less concentrated 1:100,000 or 1:200,000 solutions
T
T/ F
1:50,000 and 1:100,000 epinephrine dilution are more effective in restricting surgical blood loss than local anesthetics without vasoconstrictor additives
T
PROPRIETARY NAME
Norepinephrine
Levophed
PROPRIETARY NAME
Phenylephrine hydrochloride
Neo-Synephrine
PROPRIETARY NAME
Levonordefrin
Neo-Cobefrin
PROPRIETARY NAME
Felypressin
Octapressin
useful in treatment of anxiety, tension, ang agitation
Phenothiazine (psycho sedatives)
produce the opposite effect of alpha blocking agents
Propranolol or Inderal
SELECTION OF VASOCONSTRICTOR
→ duration of desired effect
→ length of the dental procedures
→ requirement for hemostasis
→ medical status of the patient/physical condition of the patient → concurrent medication
Norepinephrine
This is added to the cartridge to retard deterioration.
Acetone–sodium bisulfite
T/F
Norepinephrine and Phenylephrine Hydrochloride is not clinically effective in the management of bronchospasm.
T
has no effect on adrenergic nerve transmission; thus it may be safely administered to hyperthyroid patients
Felypressin
This would likely increase bleeding at the surgical site rather than minimize it.
Felypressin
It is the stablest and the weakest vasoconstrictor used in dentistry.
Phenylephrine Hydrochloride
used as a vasoconstrictor in local anes- thetics, for the management of hypotension, as a nasal decongestant, and in ophthalmic solutions to produce mydriasis.
Phenylephrine Hydrochloride
