Podcast
Questions and Answers
What is a common systemic effect of local anesthetic toxicity?
What is a common systemic effect of local anesthetic toxicity?
Which type of regional anesthesia is performed using a local anesthetic injected into a peripheral nerve?
Which type of regional anesthesia is performed using a local anesthetic injected into a peripheral nerve?
What is the primary reason most allergic reactions to local anesthetics occur?
What is the primary reason most allergic reactions to local anesthetics occur?
What is a potential use of regional anesthesia?
What is a potential use of regional anesthesia?
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Which symptom is NOT typically associated with local anesthetic toxicity?
Which symptom is NOT typically associated with local anesthetic toxicity?
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What is the primary mechanism of action of local anesthetics?
What is the primary mechanism of action of local anesthetics?
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Which factor generally increases the sensitivity of nerve fibers to local anesthetics?
Which factor generally increases the sensitivity of nerve fibers to local anesthetics?
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Which type of nerve fibers are generally less sensitive to local anesthetics?
Which type of nerve fibers are generally less sensitive to local anesthetics?
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In spinal nerves, which type of conduction failure typically occurs first due to local anesthetics?
In spinal nerves, which type of conduction failure typically occurs first due to local anesthetics?
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What must local anesthetics do to effectively enter the neuron?
What must local anesthetics do to effectively enter the neuron?
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Which type of local anesthetics is primarily metabolized by pseudocholinesterase?
Which type of local anesthetics is primarily metabolized by pseudocholinesterase?
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What determines the rate at which the local anesthesia effect wears off?
What determines the rate at which the local anesthesia effect wears off?
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What structural characteristic makes small diameter nerve fibers more sensitive to local anesthetics?
What structural characteristic makes small diameter nerve fibers more sensitive to local anesthetics?
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What is the primary enzyme responsible for hydrolyzing acetylcholine more slowly than acetylcholinesterase?
What is the primary enzyme responsible for hydrolyzing acetylcholine more slowly than acetylcholinesterase?
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Which factor does NOT affect the minimum concentration of local anesthetic needed to block nerve impulse conduction?
Which factor does NOT affect the minimum concentration of local anesthetic needed to block nerve impulse conduction?
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What correlates with the potency of local anesthetics?
What correlates with the potency of local anesthetics?
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How does the pKa of a local anesthetic affect its onset of action?
How does the pKa of a local anesthetic affect its onset of action?
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What can cause a decrease in the metabolic rate of amide local anesthetics?
What can cause a decrease in the metabolic rate of amide local anesthetics?
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Which of the following local anesthetics has the lowest pKa?
Which of the following local anesthetics has the lowest pKa?
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What characteristic do highly lipid-soluble local anesthetics share?
What characteristic do highly lipid-soluble local anesthetics share?
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What is the typical maximum dose range for local anesthetics in an individual?
What is the typical maximum dose range for local anesthetics in an individual?
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Which of the following is a common symptom associated with local anesthetic toxicity?
Which of the following is a common symptom associated with local anesthetic toxicity?
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True or False: Allergic reactions to local anesthetics are commonly reported and occur frequently.
True or False: Allergic reactions to local anesthetics are commonly reported and occur frequently.
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Name one type of regional anesthesia.
Name one type of regional anesthesia.
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One potential use of regional anesthesia includes providing __________ during labor and delivery.
One potential use of regional anesthesia includes providing __________ during labor and delivery.
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What is a rare effect of tissue toxicity from local anesthetics?
What is a rare effect of tissue toxicity from local anesthetics?
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True or False: Local anesthetics can only provide anesthesia for surgical procedures.
True or False: Local anesthetics can only provide anesthesia for surgical procedures.
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What is the effect of local anesthetic toxicity at high concentrations?
What is the effect of local anesthetic toxicity at high concentrations?
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Local anesthetic reactions that are often reported as allergies are frequently due to previous __________ injections.
Local anesthetic reactions that are often reported as allergies are frequently due to previous __________ injections.
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Match the type of regional anesthesia with its description:
Match the type of regional anesthesia with its description:
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List one of the systemic toxic effects of local anesthetics.
List one of the systemic toxic effects of local anesthetics.
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What is the primary effect of local anesthetics on nerve function?
What is the primary effect of local anesthetics on nerve function?
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The larger the diameter of a nerve fiber, the more sensitive it is to local anesthetics.
The larger the diameter of a nerve fiber, the more sensitive it is to local anesthetics.
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What type of ion channels do local anesthetics block to inhibit pain signal transmission?
What type of ion channels do local anesthetics block to inhibit pain signal transmission?
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Local anesthetics must lose their hydrogen ions to ______ across the cellular membrane.
Local anesthetics must lose their hydrogen ions to ______ across the cellular membrane.
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Match the following nerve fiber types with their sensitivity to local anesthetics:
Match the following nerve fiber types with their sensitivity to local anesthetics:
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Which class of local anesthetics is primarily metabolized by pseudocholinesterase?
Which class of local anesthetics is primarily metabolized by pseudocholinesterase?
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Local anesthetics can produce their effects only during neuronal depolarization.
Local anesthetics can produce their effects only during neuronal depolarization.
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The correct sequence of local anesthetic inhibition in spinal nerves is ______ > sensory > motor.
The correct sequence of local anesthetic inhibition in spinal nerves is ______ > sensory > motor.
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What happens to local anesthetics once they enter a neuron?
What happens to local anesthetics once they enter a neuron?
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Sensitivity to local anesthetics in nerve fibers is primarily determined by which of the following?
Sensitivity to local anesthetics in nerve fibers is primarily determined by which of the following?
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Which enzyme hydrolyzes acetylcholine more slowly than acetylcholinesterase?
Which enzyme hydrolyzes acetylcholine more slowly than acetylcholinesterase?
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Potency of local anesthetics decreases with higher lipid solubility.
Potency of local anesthetics decreases with higher lipid solubility.
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What physiological conditions can reduce the metabolic rate of amide local anesthetics?
What physiological conditions can reduce the metabolic rate of amide local anesthetics?
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The pKa of a local anesthetic represents the pH at which the fraction of ionized and nonionized drug is ______.
The pKa of a local anesthetic represents the pH at which the fraction of ionized and nonionized drug is ______.
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Match the following local anesthetics with their corresponding pKa values:
Match the following local anesthetics with their corresponding pKa values:
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What factor antagonizes the block of local anesthetics?
What factor antagonizes the block of local anesthetics?
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The onset of local anesthetic action is influenced by the lipid solubility of the anesthetic.
The onset of local anesthetic action is influenced by the lipid solubility of the anesthetic.
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Name the type of anesthetics that are primarily metabolized by microsomal P-450 enzymes in the liver.
Name the type of anesthetics that are primarily metabolized by microsomal P-450 enzymes in the liver.
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Highly lipid-soluble local anesthetics generally have a ______ duration of action.
Highly lipid-soluble local anesthetics generally have a ______ duration of action.
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What is the typical maximum dose range for an individual receiving local anesthetics?
What is the typical maximum dose range for an individual receiving local anesthetics?
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Which of the following is NOT a specific type of regional anesthesia?
Which of the following is NOT a specific type of regional anesthesia?
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True or False: Systemic toxicity from local anesthetics is commonly seen in clinical practice.
True or False: Systemic toxicity from local anesthetics is commonly seen in clinical practice.
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Name one systemic toxic effect associated with local anesthetics.
Name one systemic toxic effect associated with local anesthetics.
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True allergies to local anesthetics are __________.
True allergies to local anesthetics are __________.
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Match the regional anesthesia types with their descriptions:
Match the regional anesthesia types with their descriptions:
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What is a rare local anesthetic tissue toxicity effect?
What is a rare local anesthetic tissue toxicity effect?
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True or False: Local anesthetics can cause shivering or twitching as a common toxic effect.
True or False: Local anesthetics can cause shivering or twitching as a common toxic effect.
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What commonly reported patient symptom may be mistakenly labeled as an allergy to local anesthetics?
What commonly reported patient symptom may be mistakenly labeled as an allergy to local anesthetics?
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Regional anesthesia is used to provide __________ during surgical procedures.
Regional anesthesia is used to provide __________ during surgical procedures.
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Match the following toxic effects with their categories:
Match the following toxic effects with their categories:
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Which nerve fibers are generally more sensitive to local anesthetics?
Which nerve fibers are generally more sensitive to local anesthetics?
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Local anesthetics produce loss of sensation without causing loss of consciousness.
Local anesthetics produce loss of sensation without causing loss of consciousness.
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What is the primary mechanism through which local anesthetics block pain signal transmission?
What is the primary mechanism through which local anesthetics block pain signal transmission?
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Local anesthetics need to lose their __________ ions to effectively diffuse across the cellular membrane.
Local anesthetics need to lose their __________ ions to effectively diffuse across the cellular membrane.
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Match the following nerve fibers with their sensitivity to local anesthetics:
Match the following nerve fibers with their sensitivity to local anesthetics:
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What sequence typically occurs in spinal nerves due to local anesthetic inhibition?
What sequence typically occurs in spinal nerves due to local anesthetic inhibition?
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Larger diameter nerve fibers are more sensitive to local anesthetics than smaller diameter fibers.
Larger diameter nerve fibers are more sensitive to local anesthetics than smaller diameter fibers.
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What guides the effectiveness and duration of the local anesthetic effect?
What guides the effectiveness and duration of the local anesthetic effect?
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Ester local anesthetics are primarily metabolized by __________.
Ester local anesthetics are primarily metabolized by __________.
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Which type of local anesthetics are primarily metabolized by microsomal P-450 enzymes?
Which type of local anesthetics are primarily metabolized by microsomal P-450 enzymes?
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Which of the following statements about ester hydrolysis is true?
Which of the following statements about ester hydrolysis is true?
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Decreases in hepatic function increase the metabolic rate of amide local anesthetics.
Decreases in hepatic function increase the metabolic rate of amide local anesthetics.
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What is the primary effect of the pKa on local anesthetic action?
What is the primary effect of the pKa on local anesthetic action?
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The anesthetics that are primarily metabolized by _______ are known as amide local anesthetics.
The anesthetics that are primarily metabolized by _______ are known as amide local anesthetics.
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Match the local anesthetics with their corresponding pKa values:
Match the local anesthetics with their corresponding pKa values:
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What aspect directly correlates with the potency of local anesthetics?
What aspect directly correlates with the potency of local anesthetics?
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Highly lipid-soluble local anesthetics generally have a shorter duration of action.
Highly lipid-soluble local anesthetics generally have a shorter duration of action.
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The concentration of local anesthetic needed to block nerve impulse conduction is impacted by fiber size, type, and _______, among other factors.
The concentration of local anesthetic needed to block nerve impulse conduction is impacted by fiber size, type, and _______, among other factors.
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What physiological conditions can antagonize local anesthetic blockade?
What physiological conditions can antagonize local anesthetic blockade?
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What is the typical maximum dose range for local anesthetics administered to an individual?
What is the typical maximum dose range for local anesthetics administered to an individual?
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Which of the following is NOT a common symptom associated with local anesthetic toxicity?
Which of the following is NOT a common symptom associated with local anesthetic toxicity?
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True or False: Most allergic reactions to local anesthetics are true allergies rather than reactions to ester class hydrolysis.
True or False: Most allergic reactions to local anesthetics are true allergies rather than reactions to ester class hydrolysis.
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Name one type of regional anesthesia.
Name one type of regional anesthesia.
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Local anesthetic toxicity can lead to __________, which may include symptoms ranging from lightheadedness to seizures.
Local anesthetic toxicity can lead to __________, which may include symptoms ranging from lightheadedness to seizures.
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Match the following types of regional anesthesia with their descriptions:
Match the following types of regional anesthesia with their descriptions:
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Which type of anesthesia is primarily used for chronic pain syndromes?
Which type of anesthesia is primarily used for chronic pain syndromes?
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True or False: Tissue toxicity from local anesthetics is common and widely reported.
True or False: Tissue toxicity from local anesthetics is common and widely reported.
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What is a potential effect of high concentrations of local anesthetics?
What is a potential effect of high concentrations of local anesthetics?
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The __________ block is performed using a local anesthetic injected into a peripheral nerve.
The __________ block is performed using a local anesthetic injected into a peripheral nerve.
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Which of the following statements about local anesthetic allergies is true?
Which of the following statements about local anesthetic allergies is true?
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Which nerve fibers are generally more resistant to inhibition by local anesthetics?
Which nerve fibers are generally more resistant to inhibition by local anesthetics?
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Local anesthetics can be used without causing any loss of sensation in the entire body.
Local anesthetics can be used without causing any loss of sensation in the entire body.
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What is the primary mechanism by which local anesthetics prevent pain transmission?
What is the primary mechanism by which local anesthetics prevent pain transmission?
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Larger, faster Aα fibers are generally __________ sensitive to local anesthetics than smaller, slower Aδ fibers.
Larger, faster Aα fibers are generally __________ sensitive to local anesthetics than smaller, slower Aδ fibers.
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Match the type of local anesthetics with their metabolism:
Match the type of local anesthetics with their metabolism:
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What must local anesthetics do to diffuse through the cellular membrane?
What must local anesthetics do to diffuse through the cellular membrane?
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Sensitivity of nerve fibers to local anesthetics is solely determined by their diameter.
Sensitivity of nerve fibers to local anesthetics is solely determined by their diameter.
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In what sequence does local anesthetic inhibition generally occur in spinal nerves?
In what sequence does local anesthetic inhibition generally occur in spinal nerves?
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The action of local anesthetics generally wears off as they __________ throughout the body.
The action of local anesthetics generally wears off as they __________ throughout the body.
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What determines the overall sensitivity of nerve fibers to local anesthetics?
What determines the overall sensitivity of nerve fibers to local anesthetics?
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What enzyme is responsible for hydrolyzing acetylcholine more slowly than acetylcholinesterase?
What enzyme is responsible for hydrolyzing acetylcholine more slowly than acetylcholinesterase?
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Ester local anesthetics are metabolized by microsomal P-450 enzymes in the liver.
Ester local anesthetics are metabolized by microsomal P-450 enzymes in the liver.
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Which factor affects the minimum concentration of local anesthetic that will block nerve impulse conduction?
Which factor affects the minimum concentration of local anesthetic that will block nerve impulse conduction?
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The duration of action of local anesthetics correlates with _____ and lipid solubility.
The duration of action of local anesthetics correlates with _____ and lipid solubility.
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Match the following local anesthetics with their corresponding pKa values:
Match the following local anesthetics with their corresponding pKa values:
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Which of the following conditions can reduce the metabolic rate of amide local anesthetics?
Which of the following conditions can reduce the metabolic rate of amide local anesthetics?
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Higher lipid solubility decreases the duration of action of local anesthetics.
Higher lipid solubility decreases the duration of action of local anesthetics.
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What is the typical maximum dose range for local anesthetics in an individual?
What is the typical maximum dose range for local anesthetics in an individual?
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The pKa is the pH at which the fraction of ionized and nonionized drug is _____ .
The pKa is the pH at which the fraction of ionized and nonionized drug is _____ .
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Which of the following is a factor that antagonizes the blockade by local anesthetics?
Which of the following is a factor that antagonizes the blockade by local anesthetics?
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What is the primary mechanism by which local anesthetics block pain signal transmission?
What is the primary mechanism by which local anesthetics block pain signal transmission?
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Smaller diameter nerve fibers are generally less sensitive to local anesthetics than larger diameter fibers.
Smaller diameter nerve fibers are generally less sensitive to local anesthetics than larger diameter fibers.
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Which class of local anesthetics is primarily metabolized by pseudocholinesterase?
Which class of local anesthetics is primarily metabolized by pseudocholinesterase?
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Once inside the neuron, local anesthetics regain their __________ form.
Once inside the neuron, local anesthetics regain their __________ form.
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Match the nerve fiber type with its sensitivity to local anesthetics:
Match the nerve fiber type with its sensitivity to local anesthetics:
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Which of the following factors increases sensitivity to local anesthetics?
Which of the following factors increases sensitivity to local anesthetics?
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Local anesthetic effects wear off gradually as they remain in high concentration.
Local anesthetic effects wear off gradually as they remain in high concentration.
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What happens to local anesthetics in their active form once they enter a neuron?
What happens to local anesthetics in their active form once they enter a neuron?
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In spinal nerves, the typical sequence of local anesthetic inhibition is __________ > sensory > motor.
In spinal nerves, the typical sequence of local anesthetic inhibition is __________ > sensory > motor.
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What structural characteristic makes small diameter nerve fibers more sensitive to local anesthetics?
What structural characteristic makes small diameter nerve fibers more sensitive to local anesthetics?
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What is one of the systemic toxic effects of local anesthetics?
What is one of the systemic toxic effects of local anesthetics?
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True or False: Local anesthetics can cause seizures only in high concentrations.
True or False: Local anesthetics can cause seizures only in high concentrations.
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Name one common symptom of local anesthetic toxicity.
Name one common symptom of local anesthetic toxicity.
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Local anesthetics are very rarely associated with true __________ reactions.
Local anesthetics are very rarely associated with true __________ reactions.
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Match the types of regional anesthesia with their descriptions:
Match the types of regional anesthesia with their descriptions:
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Which of the following can be a use of regional anesthesia?
Which of the following can be a use of regional anesthesia?
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True or False: Tissue toxicity from local anesthetics can occur at clinically used concentrations.
True or False: Tissue toxicity from local anesthetics can occur at clinically used concentrations.
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What is a rare effect associated with systemic toxicity from local anesthetics?
What is a rare effect associated with systemic toxicity from local anesthetics?
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Glucose metabolism is __________ when using amide local anesthetics.
Glucose metabolism is __________ when using amide local anesthetics.
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What is the primary mechanism through which local anesthetics achieve pain relief?
What is the primary mechanism through which local anesthetics achieve pain relief?
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What effect does a decrease in hepatic function have on amide local anesthetics?
What effect does a decrease in hepatic function have on amide local anesthetics?
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The pKa of a local anesthetic is the pH at which the fraction of ionized and nonionized drug is unequal.
The pKa of a local anesthetic is the pH at which the fraction of ionized and nonionized drug is unequal.
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What is the primary enzyme responsible for hydrolyzing acetylcholine quickly?
What is the primary enzyme responsible for hydrolyzing acetylcholine quickly?
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The duration of action of highly lipid-soluble local anesthetics is ______.
The duration of action of highly lipid-soluble local anesthetics is ______.
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Match the following local anesthetics with their corresponding pKa values:
Match the following local anesthetics with their corresponding pKa values:
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Which factor can antagonize the block of local anesthetics?
Which factor can antagonize the block of local anesthetics?
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Larger diameter nerve fibers are more sensitive to local anesthetics than smaller diameter fibers.
Larger diameter nerve fibers are more sensitive to local anesthetics than smaller diameter fibers.
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What is the role of pseudocholinesterase in the metabolism of certain anesthetics?
What is the role of pseudocholinesterase in the metabolism of certain anesthetics?
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The minimum concentration of local anesthetic needed to block nerve conduction is affected by fiber size, type, myelination, pH, and ______.
The minimum concentration of local anesthetic needed to block nerve conduction is affected by fiber size, type, myelination, pH, and ______.
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Which local anesthetic has the lowest pKa?
Which local anesthetic has the lowest pKa?
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Allergic reactions to local anesthetics are commonly reported and occur frequently.
Allergic reactions to local anesthetics are commonly reported and occur frequently.
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Systemic toxicity from local anesthetics can lead to symptoms such as seizures and hypotension.
Systemic toxicity from local anesthetics can lead to symptoms such as seizures and hypotension.
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Topical anesthesia is a type of regional anesthesia.
Topical anesthesia is a type of regional anesthesia.
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Numbness is a common symptom associated with local anesthetic toxicity.
Numbness is a common symptom associated with local anesthetic toxicity.
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Local anesthetics only provide analgesia during surgical procedures.
Local anesthetics only provide analgesia during surgical procedures.
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Local anesthetic toxicity can occur if administered in high enough concentrations.
Local anesthetic toxicity can occur if administered in high enough concentrations.
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The ester class of local anesthetics is associated with a higher rate of true allergic reactions.
The ester class of local anesthetics is associated with a higher rate of true allergic reactions.
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A Bier block is a type of intravenous regional anesthesia.
A Bier block is a type of intravenous regional anesthesia.
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Shivering or twitching is a sign of allergic reaction to local anesthetics.
Shivering or twitching is a sign of allergic reaction to local anesthetics.
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Local anesthetics can cause CNS/cardiovascular collapse at low concentrations.
Local anesthetics can cause CNS/cardiovascular collapse at low concentrations.
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Ester hydrolysis is slower compared to amide local anesthetics.
Ester hydrolysis is slower compared to amide local anesthetics.
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The pKa of a local anesthetic indicates the pH at which the drug is fully ionized.
The pKa of a local anesthetic indicates the pH at which the drug is fully ionized.
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A decrease in hepatic function can increase the risk of systemic toxicity from local anesthetics.
A decrease in hepatic function can increase the risk of systemic toxicity from local anesthetics.
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Lipophilicity of local anesthetics correlates positively with their potency.
Lipophilicity of local anesthetics correlates positively with their potency.
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Hypokalemia can enhance the effectiveness of local anesthetics.
Hypokalemia can enhance the effectiveness of local anesthetics.
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Lidocaine and bupivacaine have the same pKa value.
Lidocaine and bupivacaine have the same pKa value.
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The onset of action for local anesthetics is faster for less potent and less lipid-soluble agents.
The onset of action for local anesthetics is faster for less potent and less lipid-soluble agents.
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Cocaine is classified as an amide local anesthetic.
Cocaine is classified as an amide local anesthetic.
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The maximum dose for local anesthetics typically ranges from 70mg to 500mg for an individual.
The maximum dose for local anesthetics typically ranges from 70mg to 500mg for an individual.
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Higher octanol solubility results in a shorter duration of action for local anesthetics.
Higher octanol solubility results in a shorter duration of action for local anesthetics.
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Local anesthetics produce loss of sensation to pain in a specific area of the body without affecting consciousness.
Local anesthetics produce loss of sensation to pain in a specific area of the body without affecting consciousness.
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Larger Aα fibers are more sensitive to local anesthetics than smaller Aδ fibers.
Larger Aα fibers are more sensitive to local anesthetics than smaller Aδ fibers.
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Local anesthetics can only produce their effects during neuronal hyperpolarization.
Local anesthetics can only produce their effects during neuronal hyperpolarization.
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The order of nerve fiber sensitivity to local anesthetics in spinal nerves follows the sequence: motor > sensory > autonomic.
The order of nerve fiber sensitivity to local anesthetics in spinal nerves follows the sequence: motor > sensory > autonomic.
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The sensitivity of nerve fibers to local anesthetics is influenced by axonal diameter and myelination.
The sensitivity of nerve fibers to local anesthetics is influenced by axonal diameter and myelination.
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C fibers, which are small and unmyelinated, are relatively resistant to inhibition by local anesthetics.
C fibers, which are small and unmyelinated, are relatively resistant to inhibition by local anesthetics.
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Local anesthetics must gain hydrogen ions to effectively diffuse across the cellular membrane.
Local anesthetics must gain hydrogen ions to effectively diffuse across the cellular membrane.
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In spinal nerves, local anesthetic inhibition affects motor fibers before sensory fibers.
In spinal nerves, local anesthetic inhibition affects motor fibers before sensory fibers.
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Local anesthetic effectiveness wears off gradually as they accumulate in the body.
Local anesthetic effectiveness wears off gradually as they accumulate in the body.
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Ester local anesthetics are mainly metabolized by liver enzymes.
Ester local anesthetics are mainly metabolized by liver enzymes.
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Tissue toxicity from local anesthetics is common and frequently observed.
Tissue toxicity from local anesthetics is common and frequently observed.
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Lightheadedness and shivering can be symptoms of local anesthetic toxicity.
Lightheadedness and shivering can be symptoms of local anesthetic toxicity.
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True allergic reactions to local anesthetics are very common.
True allergic reactions to local anesthetics are very common.
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Regional anesthesia can provide analgesia during labor and delivery.
Regional anesthesia can provide analgesia during labor and delivery.
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A Bier block is an example of a local/field type of regional anesthesia.
A Bier block is an example of a local/field type of regional anesthesia.
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Seizures can result from systemic toxicity related to local anesthetics.
Seizures can result from systemic toxicity related to local anesthetics.
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Local anesthetics must be administered in small doses to avoid toxicity.
Local anesthetics must be administered in small doses to avoid toxicity.
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Allergic reactions to local anesthetics are primarily due to amide class drugs.
Allergic reactions to local anesthetics are primarily due to amide class drugs.
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Severe toxicity from local anesthetics is often linked to the use of preservatives.
Severe toxicity from local anesthetics is often linked to the use of preservatives.
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Peripheral nerve blocks are a form of regional anesthesia.
Peripheral nerve blocks are a form of regional anesthesia.
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Ester hydrolysis is slower than amide hydrolysis.
Ester hydrolysis is slower than amide hydrolysis.
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Acetylcholine functions as a neurotransmitter in the nervous system.
Acetylcholine functions as a neurotransmitter in the nervous system.
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Higher octanol solubility correlates with lower potency of local anesthetics.
Higher octanol solubility correlates with lower potency of local anesthetics.
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The onset of action of local anesthetics is influenced by both lipid solubility and the pKa value.
The onset of action of local anesthetics is influenced by both lipid solubility and the pKa value.
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An increase in hepatic function will reduce the metabolic rate of amide local anesthetics.
An increase in hepatic function will reduce the metabolic rate of amide local anesthetics.
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Amide local anesthetics are primarily metabolized by the enzyme pseudocholinesterase.
Amide local anesthetics are primarily metabolized by the enzyme pseudocholinesterase.
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The pKa of a local anesthetic is the pH at which the fraction of ionized and nonionized drug is unequal.
The pKa of a local anesthetic is the pH at which the fraction of ionized and nonionized drug is unequal.
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Less potent local anesthetics generally have a longer onset of action compared to more potent agents.
Less potent local anesthetics generally have a longer onset of action compared to more potent agents.
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Duration of action for local anesthetics is directly related to their potency and lipid solubility.
Duration of action for local anesthetics is directly related to their potency and lipid solubility.
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The maximum dose for local anesthetics can vary widely based on patient characteristics.
The maximum dose for local anesthetics can vary widely based on patient characteristics.
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Local anesthetics produce a loss of sensation to pain in a specific area without affecting consciousness.
Local anesthetics produce a loss of sensation to pain in a specific area without affecting consciousness.
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Larger Aα fibers are more sensitive to local anesthetics compared to smaller Aδ fibers.
Larger Aα fibers are more sensitive to local anesthetics compared to smaller Aδ fibers.
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Local anesthetics block pain signal transmission by interfering with potassium ion channels.
Local anesthetics block pain signal transmission by interfering with potassium ion channels.
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C fibers are relatively resistant to inhibition by local anesthetics as compared to larger myelinated fibers.
C fibers are relatively resistant to inhibition by local anesthetics as compared to larger myelinated fibers.
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Local anesthetics must be in their ionized form to diffuse easily across the cellular membrane.
Local anesthetics must be in their ionized form to diffuse easily across the cellular membrane.
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The sequence of local anesthetic inhibition in spinal nerves is typically autonomic > sensory > motor.
The sequence of local anesthetic inhibition in spinal nerves is typically autonomic > sensory > motor.
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Small diameter nerve fibers are generally less sensitive to local anesthetics than larger fibers.
Small diameter nerve fibers are generally less sensitive to local anesthetics than larger fibers.
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Local anesthetics must regain their ionized form once inside the neuron to bind effectively.
Local anesthetics must regain their ionized form once inside the neuron to bind effectively.
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Esters are primarily metabolized in the liver by cytochrome P-450 enzymes.
Esters are primarily metabolized in the liver by cytochrome P-450 enzymes.
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The inhibition of nerve function by local anesthetics is solely a function of the anesthetic concentration in the body.
The inhibition of nerve function by local anesthetics is solely a function of the anesthetic concentration in the body.
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Study Notes
Introduction
- Local and regional anesthetics are drugs that block pain signals in specific areas of the body without causing unconsciousness.
Mechanisms of Local Anesthetic Action
- Local anesthetics block pain signal transmission by blocking sodium ion channels in peripheral neurons.
- This prevents neuronal depolarization and action potential formation.
- Local anesthetics are weak bases.
- Their positive charge prevents them from easily traversing cellular membranes.
- They must lose their hydrogen ions to diffuse.
- Once inside the neuron, they regain their ionized active form and become trapped.
- In their protonated form, molecules bind to the local anesthetic binding site on the inside of the ion channel, blocking sodium ion entrance.
- Local anesthetic effect persists as long as the concentration of molecules remains high.
- The effect gradually wears off as molecules diffuse throughout the body.
Sensitivity of Nerve Fibers
- Axonal diameter, myelination, and other anatomical and physiological factors determine the sensitivity of nerve fibers to local anesthetics.
- Smaller diameter nerves are more sensitive than larger diameter nerves.
- Unmyelinated fibers are more sensitive than myelinated fibers.
- Small unmyelinated C fibers are relatively resistant to inhibition by local anesthetics compared to larger myelinated fibers.
Nerve Fiber Classification
- In spinal nerves, local anesthetic inhibition (and conduction failure) generally follows the order: autonomic > sensory > motor.
Local Anesthetics: Classes
- Esters are metabolized by plasma cholinesterase (pseudocholinesterase).
- Ester hydrolysis is rapid, and the water-soluble metabolites are excreted in the urine.
- Amides are metabolized by microsomal P-450 enzymes in the liver.
- Decreased hepatic function or liver blood flow can lead to higher blood concentrations and increased risk of systemic toxicity.
Potency, Onset, and Duration of Action
- Potency correlates with octanol solubility, reflecting the ability of the local anesthetic to permeate lipid membranes.
- Minimum concentration needed to block nerve impulse conduction is affected by factors such as fiber size, type, myelination, pH, frequency of nerve stimulation, and electrolyte concentrations.
- Onset of action depends on lipid solubility and the relative concentrations of the nonionized and ionized forms of the drug.
- Less potent, less lipid-soluble agents generally have a faster onset than more potent, more lipid-soluble agents.
- Duration of action correlates with potency and lipid solubility. Highly lipid-soluble local anesthetics have a longer duration of action.
Toxicity
- Toxicity is related to peak circulation levels of local anesthetics.
- Maximum dose varies based on age, weight, and health.
- Common toxic effects include lightheadedness, shivering, twitching, seizures, hypotension, and numbness.
- Tissue toxicity: Can occur with high concentrations.
- Systemic Toxicity: Related to blood levels of the drug; can range from lightheadedness to seizures and cardiovascular collapse.
Allergy
- True allergy to local anesthetics is rare.
- Most reactions occur with ester class drugs due to ester hydrolysis.
- Reports of “allergy” are often caused by previous intravascular injections.
Regional Anesthesia
- Rendering a specific area of the body insensitive to stimuli for surgery or other interventions.
- Used for surgical anesthesia, post-operative analgesia, labor and delivery analgesia, and chronic pain management.
Types of Regional Anesthesia
- Topical: Applied directly to the skin or mucous membranes.
- Local/Field: Injected into the tissues surrounding a specific area.
- Intravenous Block (Bier Block): Injected into a vein to block nerve conduction.
- Peripheral Nerve Block: Injected around a specific nerve or group of nerves.
- Plexus Block: Injected into a nerve plexus, such as the brachial or lumbar plexus.
- Central Neuraxial: Injected into the spinal canal, including epidural and spinal blocks.
Local Anesthetics
- Local anesthetics transiently inhibit sensory, motor, or autonomic nerve function.
- Local anesthetics produce loss of sensation to pain in a specific area of the body without the loss of consciousness.
Mechanisms of Local Anesthetic Action
- Local anesthetics block pain signal transmission by blocking sodium ion channels in the peripheral neurons.
- This prevents neuronal depolarization and action potential formation.
- Local anesthetics are weak bases and require deprotonation to diffuse across the cellular membrane.
- Once inside the neuron, they regain their ionized active form and bind to the sodium ion channel, blocking sodium entry.
- The effect of local anesthetics lasts as long as the concentration is sufficient and wears off as they diffuse throughout the body.
Sensitivity of Nerve Fibers
- Sensitivity to local anesthetics is determined by axonal diameter, myelination, and other anatomical and physiological factors.
- Smaller diameter nerve fibers are more sensitive to local anesthetics than larger diameter fibers.
- Unmyelinated fibers are less sensitive than myelinated fibers of the same size.
Nerve Fiber Classification
- In spinal nerves, local anesthetic inhibition follows the sequence: autonomic > sensory > motor.
Local Anesthetics - Classes
Esters
- Ester local anesthetics are metabolized by pseudocholinesterase.
- This hydrolysis is rapid, and the metabolites are excreted in urine.
Amides
- Amide local anesthetics are metabolized by microsomal P-450 enzymes in the liver.
- Reduced hepatic function or blood flow can lead to higher drug concentrations and increased risk of toxicity.
Factors Affecting Local Anesthetic Action
- Potency: Correlates with octanol solubility, reflecting the ability to permeate lipid membranes.
- Minimum Blocking Concentration: Affected by fiber size, type, myelination, pH, frequency of nerve stimulation, and electrolyte concentrations.
- Onset of Action: Depends on lipid solubility and the relative concentrations of the nonionized and ionized forms of the drug.
- Duration of Action: Correlates with potency and lipid solubility. Higher lipid solubility results in longer duration.
Toxicity
- Toxicity can occur at high circulation levels of local anesthetics.
- Maximum dose varies by age, weight, and health status.
- Common toxic effects include lightheadedness, shivering or twitching, seizures, hypotension, and numbness.
- Tissue toxicity can occur at high concentrations, typically related to preservatives in the solution.
- Systemic toxicity is related to blood levels and can range from lightheadedness and tinnitus to seizures and cardiovascular collapse.
Local Anesthetics - Allergy
- True allergy is rare.
- Most reactions are to esters and their hydrolysis products.
- Patient reports of "allergy" often stem from previous intravascular injections.
Regional Anesthesia
- Regional anesthesia renders a specific area of the body insensitive to stimulus for surgery or instrumentation.
- Uses include providing anesthesia for surgery, post-operative analgesia, analgesia during labor and delivery, and diagnosing or treating chronic pain syndromes.
Types of Regional Anesthesia
- Topical
- Local/Field
- Intravenous block ("Bier" block)
- Peripheral nerve block
- Plexus block (e.g., brachial, lumbar)
- Central neuraxial (e.g., epidural, spinal)
Introduction
- Local Anesthetics (LAs) are drugs that temporarily stop nerve function, including sensation, movement, and autonomic activity.
- LAs are used to create local anesthesia, which means loss of pain sensation in a specific area without losing consciousness.
Mechanisms of Local Anesthetic Action
- LAs work by blocking pain signal transmission by blocking sodium ion channels in peripheral neurons.
- This prevents neuronal depolarization and action potential formation.
- LAs are weak bases: they need to lose their hydrogen ions to diffuse across cell membranes.
- Once inside the neuron, they regain their ionized, active form, becoming trapped inside.
- The protonated form binds to the local anesthetic binding site on the inner part of the ion channel, blocking sodium ion entry.
- LA effect persists as long as their concentration is sufficient, and fades as they diffuse away.
Nerve Fiber Classification
- Nerve fiber sensitivity to LAs depends on diameter, myelination, and other structural factors.
- Smaller diameter fibers are more sensitive to LAs than larger fibers.
- Unmyelinated fibers are less sensitive than myelinated fibers of the same size.
- The sequence of inhibition in spinal nerves is generally: autonomic > sensory > motor.
Local Anesthetics - Classes
- Esters: are metabolized by plasma cholinesterase (pseudocholinesterase).
- Amides: are metabolized by liver enzymes (microsomal P-450).
- Liver dysfunction can reduce amide metabolism, increasing blood levels and toxicity risk.
Local Anesthetic Properties
- Potency: Correlates with lipid solubility, reflecting membrane permeability.
- Onset: Dependent on lipid solubility and pKa: less potent, less lipid-soluble agents have faster onset.
- Duration: Correlates with potency and lipid solubility: highly lipid-soluble LAs have longer duration.
Local Anesthetic Toxicity
- Tissue Toxicity: Can occur with high concentration in the area where the LA is injected.
- Systemic Toxicity: Related to blood levels, typically after absorption from the injection site.
- Systemic toxicity symptoms range from mild (lightheadedness, tinnitus) to severe (seizures, cardiovascular collapse).
Local Anesthetics - Allergy
- True allergies are rare.
- Most reactions are to the ester class, due to ester hydrolysis.
- Patient reports of "allergy" are often due to previous intravascular injections.
Regional Anesthesia
- Definition: Regional Anesthesia creates insensitivity to pain in a specific area, for example, the foot, arm, or lower extremities, for surgery or other procedures.
-
Uses:
- Provides anesthesia for surgery.
- Provides analgesia after surgery or during labor and delivery.
- Diagnoses or treats chronic pain syndromes.
Types of Regional Anesthesia
- Topical
- Local/Field
- Intravenous block ("Bier" block)
- Peripheral nerve block
- Plexus block (brachial, lumbar)
- Central neuraxial block (epidural, spinal)
Local Anesthetics
- Local anesthetics block pain signal transmission by blocking sodium ion channels in peripheral neurons.
- Sodium ion channels are blocked by local anesthetics, which prevents neuronal depolarization and inhibits action potential formation.
- Local anesthetics are weak bases and they must lose their hydrogen ions in order to diffuse through the cellular membrane.
- Once inside the neuron, local anesthetics regain their ionized active form and become trapped inside.
- In the protonated form, local anesthetics bind to the local anesthesia binding site on the inside of the ion channel, near the cytoplasmic end, and block sodium ion entrance.
- The effect of local anesthetics lasts as long as the molecules remain in sufficient concentration and wears off as they diffuse throughout the body.
Nerve Fiber Classification
- The sensitivity of nerve fibers to inhibition by local anesthetics is determined by axonal diameter, myelination, and other anatomic and physiological factors.
- In the same type of nerve fiber, smaller diameter fibers are more sensitive to local anesthetics than larger fibers.
- Larger unmyelinated fibers are less sensitive to local anesthetics than smaller unmyelinated fibers.
- Small, unmyelinated C fibers are relatively resistant to inhibition by local anesthetics when compared to larger myelinated fibers.
- In spinal nerves, local anesthetic inhibition (and conduction failure) generally follows the sequence autonomic > sensory > motor.
Local Anesthetics - Classes
Esters
- Ester local anesthetics are metabolized by pseudocholinesterase (plasma cholinesterase or butyrylcholinesterase).
- Ester hydrolysis is rapid, and water-soluble metabolites are excreted in the urine.
- Pseudocholinesterase is an enzyme present in the blood and certain organs that hydrolyzes acetylcholine slower than acetylcholinesterase.
- Acetylcholinea: compound which occurs throughout the nervous system, in which it functions as a neurotransmitter.
Amides
- Amide local anesthetics are metabolized by microsomal P-450 enzymes in the liver.
- A decrease in hepatic function (e.g. cirrhosis) or liver blood flow (e.g. congestive heart failure, beta blockers, or H2-receptor blockers) can potentially reduce the metabolic rate and lead to higher blood levels of the anesthetic, which could increase the risk of systemic toxicity.
- Amide local anesthetics include: Bupivacaine, Lidocaine, Mepivacaine, Ropivacaine, and Prilocaine.
- Ester local anesthetics include: Chlorprocaine, Procaine, Cocaine, and Tetracaine.
Factors Influencing Local Anesthetic Action
- Potency correlates with octanol solubility, which reflects the ability of the local anesthetic molecule to permeate lipid membranes.
- The minimum concentration of local anesthetic that will block nerve impulse conduction is affected by factors including fiber size, type, and myelination; pH (acidic pH antagonizes block); frequency of nerve stimulation; and electrolyte concentrations (hypokalemia and hypercalcemia antagonize blockade).
- The onset of local anesthetic action depends on lipid solubility and the relative concentration of the nonionized lipid soluble form (B) and the ionized water-soluble form (BH+), expressed by the pKa.
- The pKa is the pH at which the fraction of ionized and nonionized drug is equal.
- Less potent, less lipid-soluble agents generally have a faster onset than more potent, more lipid soluble agents.
- Duration of action correlates with potency and lipid solubility.
- Highly lipid-soluble local anesthetics have a longer duration of action because they diffuse more slowly from a lipid-rich environment to the bloodstream.
Toxicity
- Toxicity is associated with peak circulation levels of local anesthetics.
- Local anesthetic concentration administered to patients varies according to age, weight, and health.
- Maximum doses for an individual usually range between 70-500 mg.
- Some common toxic effects include lightheadedness, shivering or twitching, seizures, hypotension (low blood pressure), and numbness.
Tissue Toxicity
- Can occur if administered in high enough concentrations (greater than those used clinically).
- Usually related to preservatives added to the solution.
Systemic Toxicity
- Related to blood levels of the drug secondary to absorption from the site of injection.
- Range from lightheadedness, tinnitus to seizures, and cardiovascular collapse.
Local Anesthetics - Allergy
- True allergy to local anesthetics is very rare.
- Most reactions are from the ester class due to ester hydrolysis.
- Patient reports of "allergy" are frequently due to previous intravascular injections.
Regional Anesthesia
- Regional anesthesia is used to render a specific area of the body (e.g. foot, arm, lower extremities) insensate for surgery or other procedures.
- Regional anesthesia can be used to provide anesthesia for surgical procedures, analgesia post-operatively or during labor and delivery, and as part of the diagnosis or therapy for patients with chronic pain syndromes.
Types of Regional Anesthesia
- Topical.
- Local/Field.
- Intravenous block ("Bier" block).
- Peripheral nerve block.
- Plexus - brachial, lumbar.
- Central neuraxial - epidural, spinal.
Introduction
- Local and regional anesthesia techniques rely on local anesthetics, which temporarily block sensory, motor, or autonomic nerve function.
- Local anesthetics reduce pain sensation in a specific area without causing unconsciousness.
Mechanisms of Local Anesthetic Action
- Local anesthetics prevent pain signal transmission by blocking sodium ion channels in peripheral neurons.
- This blockage inhibits neuronal depolarization and action potential formation.
- Local anesthetics are weak bases and need to lose their hydrogen ions to cross the cellular membrane.
- Once inside the neuron, they regain their ionized form and bind to the sodium ion channel, blocking sodium entry.
- The effect persists as long as the concentration is sufficient and gradually wears off as they diffuse throughout the body.
Nerve Fiber Classification
- Nerve fiber sensitivity to local anesthetics is influenced by diameter, myelination, and other factors.
- Smaller diameter fibers are more sensitive to local anesthetics than larger fibers.
- Large unmyelinated fibers are less sensitive than smaller unmyelinated fibers.
- Small unmyelinated C fibers are resistant to inhibition compared to larger myelinated fibers.
- In spinal nerves, local anesthetic inhibition typically follows the sequence: autonomic > sensory > motor.
Local Anesthetics - Classes
- Ester local anesthetics are primarily metabolized by pseudocholinesterase in the plasma.
- Ester hydrolysis is rapid, and the water-soluble metabolites are excreted in the urine.
- Amide local anesthetics are metabolized by microsomal P-450 enzymes in the liver.
- Reduced liver function can lead to higher blood concentrations and increased risk of systemic toxicity.
Local Anesthetics - Properties
- Potency correlates with octanol solubility, which reflects the ability to cross lipid membranes.
- Minimum effective concentration is influenced by fiber size, type, myelination, pH, frequency of nerve stimulation, and electrolyte concentrations.
- Onset of action is determined by lipid solubility and the relative concentration of ionized and nonionized forms of the anesthetic.
- Duration of action correlates with potency and lipid solubility.
- Highly lipid-soluble anesthetics have longer durations due to slower diffusion from lipid-rich tissues to the bloodstream.
Toxicity
- Systemic toxicity is related to peak blood levels and can range from lightheadedness and tinnitus to seizures and cardiovascular collapse.
- Tissue toxicity is rare but can occur with high local concentrations, often related to preservatives in the solution.
- Maximum recommended doses vary based on individual factors like age, weight, and health.
Local Anesthetics - Allergy
- True allergies to local anesthetics are uncommon.
- Most reactions are associated with the ester class due to ester hydrolysis.
- Reported allergies often result from previous intravascular injections.
Regional Anesthesia
- Definition: Rendering a specific area of the body insensitive to stimuli for surgery or other procedures.
- Uses: Provide anesthesia for surgery, post-operative analgesia, labor analgesia, and pain management.
- Types: Topical, local/field, intravenous block, peripheral nerve block, plexus block, and central neuraxial block (epidural, spinal).
Local Anesthetics
-
A group of drugs that transiently inhibit sensory, motor, or autonomic nerve function by blocking sodium ion channels in peripheral neurons.
- This prevents neuronal depolarization and action potential formation.
-
Local anesthetics are weak bases that need to lose their hydrogen ions to diffuse across the cellular membrane.
- They regain their ionized active form once inside the neuron and block sodium ion entry.
-
Sensitivity to local anesthetics is determined by axonal diameter, myelination, and other anatomical and physiological factors.
- Smaller diameter fibers are more sensitive to local anesthetics.
- Larger, faster Aα fibers are less sensitive than smaller, slower Aδ fibers.
- Larger unmyelinated fibers are less sensitive than smaller unmyelinated fibers.
- Small unmyelinated C fibers are relatively resistant to inhibition compared to larger myelinated fibers.
- In spinal nerves, local anesthetic inhibition generally follows the sequence: autonomic > sensory > motor.
Local Anesthetic Classes
-
Ester local anesthetics (e.g., procaine, cocaine, tetracaine) are metabolized by pseudocholinesterase.
- Ester hydrolysis is very rapid, and the water-soluble metabolites are excreted in the urine.
-
Amide local anesthetics (e.g., lidocaine, bupivacaine, mepivacaine) are metabolized by microsomal P-450 enzymes in the liver.
- Decreased hepatic function or liver blood flow can lead to higher blood concentrations and an increased risk of systemic toxicity.
Local Anesthetic Characteristics
- Potency correlates with octanol solubility, which reflects the ability of the molecule to permeate lipid membranes.
- The minimum concentration needed for nerve impulse conduction is influenced by factors like fiber size, type, myelination, pH, frequency of nerve stimulation, and electrolyte concentrations.
- Onset of action depends on lipid solubility and the relative concentration of the nonionized lipid-soluble form (B) and the ionized water-soluble form (BH+), which is expressed by the pKa.
- Less potent, less lipid-soluble agents generally have a faster onset.
-
Duration of action correlates with potency and lipid solubility.
- Highly lipid-soluble local anesthetics have a longer duration of action as they diffuse more slowly from a lipid-rich environment to the bloodstream.
Local Anesthetic Toxicity
-
Toxicity is related to peak circulation levels of local anesthetics.
- Levels administered are varied based on age, weight, and health.
- Maximum dose for an individual is usually between 70mg to 500mg.
- Common toxic effects: Lightheadedness, shivering or twitching, seizures, hypotension, and numbness.
- Tissue toxicity (rare) can occur at high concentrations.
-
Systemic toxicity (rare) is related to blood levels of the drug secondary to absorption from the injection site.
- Can range from lightheadedness and tinnitus to seizures and cardiovascular collapse.
Local Anesthetic Allergy
- True allergy is very rare.
- Most reactions are related to the ester class due to ester hydrolysis.
- Patient reports of "allergy" are frequently due to previous intravascular injections.
Regional Anesthesia
- Rendering a specific area of the body (e.g., foot, arm, lower extremities) insensate to stimulus for surgery or other procedures.
-
Uses:
- Provide anesthesia for surgical procedures.
- Provide postoperative analgesia or analgesia during labor and delivery.
- Diagnosis or therapy for patients with chronic pain syndromes.
-
Types:
- Topical.
- Local/Field.
- Intravenous block ("Bier" block).
- Peripheral nerve block.
- Plexus block (brachial, lumbar).
- Central neuraxial (epidural, spinal).
Local Anesthetics
- Local anesthetics are drugs that temporarily block sensory, motor, or autonomic nerve function.
- They produce a loss of sensation to pain in a specific area of the body without causing loss of consciousness.
- Local anesthetics block pain signal transmission by blocking sodium ion channels in peripheral neurons.
Mechanisms of Action
- Local anesthetics prevent neuronal depolarization and action potential formation.
- Local anesthetics are weak bases.
- Their positive charge prevents them from readily traversing cellular membranes.
- They must lose their hydrogen ions to diffuse across the membrane.
- Once inside the neuron they regain their ionized active form.
- They bind to the local anesthetic binding site on the inside of the ion channel.
- This blocks sodium ion entrance and prevents impulse transmission.
Nerve Fiber Classification
- The sensitivity of nerve fibers to local anesthetics is determined by axonal diameter, myelination, and other anatomical and physiological factors.
- Larger, myelinated fibers are less sensitive to local anesthetics than smaller, unmyelinated fibers.
Local Anesthetics - Classes
- There are two main classes of local anesthetics: esters and amides.
- Esters are mostly metabolized by pseudocholinesterase in the plasma.
- Amides are metabolized by microsomal P-450 enzymes in the liver.
Factors Affecting Local Anesthesia
- Potency correlates with octanol solubility.
- Minimum blocking concentration is affected by fiber size, type, myelination, pH, frequency of nerve stimulation, and electrolyte concentrations..
- Onset of action depends on lipid solubility and the relative concentration of the nonionized and ionized forms of the drug.
- Duration of action correlates with potency and lipid solubility.
Local Anesthetics - Toxicity
- Tissue Toxicity: Can occur with high concentrations of local anesthetics.
- Systemic Toxicity: Related to blood levels of the drug, and can range from lightheadedness to seizures and cardiovascular collapse
- The maximum dose for an individual is usually between 70 mg to 500 mg.
Regional Anesthesia
- Regional anesthesia renders a specific area of the body insensitive to stimulus.
- This can be used for surgical procedures, postoperative pain management, childbirth, and diagnosis/treatment of chronic pain syndromes.
Types of Regional Anesthesia
- Topical: Applied to the surface of the skin.
- Local/Field: Injected into the tissues surrounding the target area.
- Intravenous Block (“Bier Block”): Injected into a vein.
- Peripheral Nerve Block: Injected near a specific nerve.
- Plexus Block: Injected near a nerve plexus.
- Central Neuraxial: Injected into the epidural or spinal space.
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Test your knowledge on local and regional anesthetics! This quiz covers the mechanisms of action, the sensitivity of nerve fibers, and the pharmacodynamics of local anesthetics. Perfect for students studying pharmacology or anesthesia.
