2/6/25, 1:43 AM Local ananthesia
Local Anesthetics
ILOs:
1-Define local anesthetics.
2-Recognize techniques of local anesthesia.
3-Classify local anesthetics.
4-Recognize adverse effects of local anesthetics.
5-Explain the mechanism of action of local anesthetics
Definition:
sensation without the loss of consciousness or the impairment of central
control of vital functions.
general anesthesia, and/or to provide postoperative analgesia.
Mechanism of action:
1-Local anesthetics act at the cell membrane to prevent the generation and
the conduction of nerve impulses.
blockade of
voltage-gated sodium channels.
-Local anesthetics block conduction by decreasing the large transient
increase in the permeability of excitable membranes to Na+ by direct
interaction with voltage gated Na+ channels
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, 2/6/25, 1:43 AM Local ananthesia
-Local anesthetics bind more readily to the Na+ channel during
depolarization (when it is open or activated).
anesthetics.
um
channel.
2-At higher concentrations, local anesthetics can block k+ channels.
3-Also, high concentrations of local anesthetics can block Ca+2 channels.
Undesired effects of local anesthetics:
nervous system, local anesthetics interfere with the function of all organs
in which conduction or transmission of impulses occurs.
to the
concentration of local anesthetic achieved in the circulation.
1-CNS:
disturbances and restlessness.
metallic taste.
overt tonic clonic convulsions.
NB:
pathways thereby allowing unopposed activity of excitatory neuronal
pathways. This transitional stage of unbalanced excitation (i.e: seizure
activity) is then followed by generalized CNS depression.
2-Neurotoxicity:
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Local Anesthetics
ILOs:
1-Define local anesthetics.
2-Recognize techniques of local anesthesia.
3-Classify local anesthetics.
4-Recognize adverse effects of local anesthetics.
5-Explain the mechanism of action of local anesthetics
Definition:
sensation without the loss of consciousness or the impairment of central
control of vital functions.
general anesthesia, and/or to provide postoperative analgesia.
Mechanism of action:
1-Local anesthetics act at the cell membrane to prevent the generation and
the conduction of nerve impulses.
blockade of
voltage-gated sodium channels.
-Local anesthetics block conduction by decreasing the large transient
increase in the permeability of excitable membranes to Na+ by direct
interaction with voltage gated Na+ channels
about:blank 1/8
, 2/6/25, 1:43 AM Local ananthesia
-Local anesthetics bind more readily to the Na+ channel during
depolarization (when it is open or activated).
anesthetics.
um
channel.
2-At higher concentrations, local anesthetics can block k+ channels.
3-Also, high concentrations of local anesthetics can block Ca+2 channels.
Undesired effects of local anesthetics:
nervous system, local anesthetics interfere with the function of all organs
in which conduction or transmission of impulses occurs.
to the
concentration of local anesthetic achieved in the circulation.
1-CNS:
disturbances and restlessness.
metallic taste.
overt tonic clonic convulsions.
NB:
pathways thereby allowing unopposed activity of excitatory neuronal
pathways. This transitional stage of unbalanced excitation (i.e: seizure
activity) is then followed by generalized CNS depression.
2-Neurotoxicity:
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