Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
NU 600
Exam 5 - Local Anesthetics
| Question | Answer |
|---|---|
| Nerve cells communicate w/other cells via _________ messages. | ionic |
| What are nerve cells known as? | Excitable cells |
| What is the excitability of a cell based on? | Structure of the cell membrane and components |
| All the parts within a cell are called _________. | Organelles |
| What are the 3 primary structures of the nerve cell anatomy? | Dendrites, nerve cell body, axon |
| The area where information from neurons communicates with other nerve cells is called the _________. | Dendritic zone |
| The charge of the extracellular environment is __________, and the intracellular environment is _________. | Positive; negative |
| The elongated portion of the nerve cell body is called the ___________. | Axon |
| What are dendrites? | Outfoldings and branched projections of a neuron that conduct electrochemical stimulation rec'd from another neuron to the cell body from which the dendrites project |
| What is axoplasm? What is its function? | Intracellular fluid; movement of energy and waste material |
| Transport of materials within the axoplasm is facilitated through what structure? | Microtubules |
| Microtubules transport intracellular contents between what two structures? | Cell body and end of the axon |
| What is the receptive part of a neuron referred to as? | Dendritic zone |
| The dendritic zone is often (small/larger) than the cell body. | Larger |
| The outfoldings of the nerve cell membrane are called ______. | Dendrites |
| Where is the site for initiation of excitability? | Dendrites |
| The original sensory signal (is/is not) modified as it travels from peripheral sensory and motor neurons to the brain. | Is—the original signal is modified by dendritic anatomy |
| Nerve cells are dependent on what substance in order to transmit electrochemical signals? | ATP |
| Both the extracellular fluid and intracellular fluid of the neuron are (water/lipid) based. | water |
| What does the nerve cell membrane serve as a barrier against? | Ionic movement |
| Where does ionic movement occur? | Gaps, called ion channels, formed by lipoproteins |
| The cells that protect axons are called ________ in the PNS, and _____________ in the CNS. | Schwann cell; oligodendrocyte |
| What does the distance between gaps of a myelinated axon related to? | Local anesthetic action |
| What are Schwann cells responsible for? | Enzyme and myelin synthesis, metabolic needs |
| How many times do Schwann cells wrap myelin around an axon? | B/w 50-200 revolutions |
| What are the functions of the myelin sheath? | Insulates and protects the neuron |
| Intervals between the nodes of Ranvier occur at intervals of about _______ mm. | 1 |
| The density of Na channels within the nodes of Ranvier is (high/low). | High |
| What is saltatory conduction? | The propagation of action potentials along myelinated axons from one node of Ranvier to the next, increasing conduction velocity of action potentials |
| The terminal end of the axon is also called the ______. | Synaptic terminal |
| What part of the nerve cell is involved w/electrical conduction? | Nerve cell membrane |
| What is the main structural component of the nerve cell membrane? | Rows of phospholipid molecules |
| What are the most active ions for excitable membranes? | Potassium, sodium, calcium |
| How does movement in sodium channels differ from movement in potassium channels. | Sodium=channels are either opened or closed and determined by changes in voltage; potassium=moves freely down electrical gradients |
| Describe how the nerve cell membrane is a semipermeable membrane. | Freely allows for potassium to accumulate in the axoplasm, but blocks the movement of sodium |
| What serves as the basis for conduction? | Na-K gradient and the energy dependent enzyme systems that maintain the gradient |
| The movement of potassium is (free/restricted), while the movement of sodium is (free/restricted). | Free; restricted |
| Why does an electrical gradient exist between the intra- and extra- cellular environments? | The free movement of potassium creates the gradient against the restricted movement of sodium |
| How fast does peripheral nerve conduction occur? | 45-60meters/sec |
| How fast do unmyelinated fibers conduct impulses? | As low as 0.7meters/sec |
| Voltage is mainly determined by the movement of what electrolyte? | Potassium |
| What is the charge on the inside of the cell? -70 to -90mV | -70 to -90mV |
| What is the equilibrium potential? | The state of equilibrium maintained by the balance of chemical forces that move cations in one direction and equal electrical forces in the opposite direction |
| Stimuli that generate an impulse are created through what three means? | Mechanical, chemical, electrical |
| What does the neuron membrane generate in response to environmental stimuli? | Action potential |
| How is an action potential triggered? | Depolarization of the membrane beyond threshold |
| How else are action potentials referred as? | Impulses or nerve impulses |
| Depolarization occurs until what voltage is reached? | 15mV |
| What is the total excursion of amplitude? | 110mV (-70mV to 40mV) |
| What initiates the rapid reversal of depolarization? | The movement of potassium down its concentration gradient |
| What ultimately restores the cell back to its baseline polarized state and ready for the next propagation? | Energy dependent transport of sodium out of the cell, and passive movement of potassium back into the cell. |
| What does “propagation” of an action potential refer to? | Depolarization that occurs at one node causes voltage changes that initiate the process at the next distal site |
| Define nerve conduction. | The propagation of a signal that occurs throughout the length of an intact nerve |
| Nerve fibers are divided into three groups based on what three characteristics? | Diameter, conduction, velocity |
| “A” nerve fibers are (unmyelinated/myelinated) and (rapid/slow) conductors of nerve signals. | Myelinated; rapid |
| What functions do “A” fibers process? | Sensory, motor, and muscle impulses |
| “B” fibers are (larger/smaller) than “A” fibers. | Smaller |
| “B” fibers are (myelinated/unmyelinated) and (rapid/slow) conductors. | Myelinated; slow |
| What functions do “B” fibers process? | Pre-ganglionic, autonomic |
| Which nerve fibers are the smallest? Are they myelinated or unmyelinated? | C fibers; unmyelinated |
| What are the subgroups of “A” fibers? | Alpha, beta, gamma, delta |
| What part of the nerve cell membrane is most responsible for nerve signal propagation? | Sodium channel |
| Sodium channels (are/are not) selective for sodium. | Are |
| Ion selectivity, specifically for sodium, is provided by what feature? | Filters |
| How are sodium channels opened and closed? | Through voltage-controlled gating |
| How many times does sodium move more freely through a sodium channel compared to potassium? | 100x |
| How much sodium is able to move through a potassium channel? | Almost none |
| Why is sodium unable to pass through a potassium channel? | It is highly charged and associated w/more water molecules |
| How is the opening and closing of sodium channels physically controlled? | By confirmational changes in structural proteins |
| *BONUS* LA best bind to sodium channels when the channels are in what two states? | Open or inactive |
| What is an amphiphatic molecule? | A molecule that results from the combination of 2 diverse groups |
| What are the two diverse groups of an LA and how are they joined? | One end of the LA is lipophilic and the other is hydrophliic; they are joined by an intermediate chain |
| The lipophilic end of the LA is composed of a _______. | Benzene ring |
| Which end of the LA is the first to enter the neuron? | Lipophilic, or benzene ring |
| The intermediate chain is composed of a _______. | Hydrocarbon |
| The hydrophilic end of the LA is composed of a ________. | Tertiary amine |
| Where does the differentiation occur that creates either an ester or amide LA? | The linkage within the intermediate chain that connects it to the benzene ring |
| The majority of LA are classified as ______. | Tertiary amines |
| Tertiary amines are derivatives of what chemical? | Ammonia |
| Ammonia is a (weak/strong) base. | Weak |
| The blockade of what type of channel leads to the interruption of neural activity? | Sodium channel |
| How is the ability of a LA to block a sodium channel determined? | Affinity of the hydrophilic end of the LA for the axoplasmic side of the sodium channel |
| How does increasing the length of the hydrocarbon substitutions of the tertiary amine affect the characteristics of a local anesthetic? | Increases the lipophilicity and potency |
| What part of an LA molecule can be altered to increase its potency? | The tertiary amine by lengthening it |
| The length of the intermediate chain must be b/w what two carbon lengths? | 3 and 7 |
| How much activity will an LA have with an intermediate chain length of 2? | None |
| Where does the first step in the biotransformation of an LA occur? | The intermediate bond |
| What part of the LA determines its metabolism? | Intermediate bond |
| What chemical is the aminoester group derived from? | Benzoic acid |
| The intermediate bond of an aminoester is subject to what type of metabolism? | Rapid hydrolysis w/plasma cholinesterase |
| The ½ life of aminoesters is (short/long). | Short |
| The amide group is derived from what organic compound? | Aniline |
| What two steps does the metabolism of an amide require? | Biotransformation conjugation |
| Where does the metabolism of an aminoamide occur? | Liver |
| How is potency and toxicity of the aminoamide determined? | First by redistribution then elimination |
| What component of the LA is required to facilitate uptake into the neuron? | Lipophilic component (benzene ring) |
| The potency of the LA is r/t to the ________. | Lipid solubility |
| What portion of the LA occupies the sodium channel of the nerve cell? | Tertiary amine |
| What determines the alignment of the tertiary amine to the sodium channel? | Opposing forces of the ends of the LA, and the length of the intermediate chain |
| The occupation of the sodium channel by the LA occurs on which side of the nerve cell? | Axoplasmic, or intracellular |
| What is the onset of LA action related to? | The ability of the LA to diffuse into a lipid matrix |
| How are the majority of LA solutions prepared and what does their specific gravity resemble? | Prepared plain w/sp. gravity close to H20 |
| What does baricity refer to? | The density of a substance compared to the density of CSF |
| How is baricity used in anesthesia? | Determines the manner in which a drug will spread in the intrathecal space |
| ______ is added to a LA to make it heavier. | Glucose |
| LA solutions are (hypo/hyper)baric compared to CSF at body temperature. | Hypo |
| The typical LA molecule is a __________ and a __________. | Tertiary amine; weak base |
| The typical LA molecule is (highly/poorly) soluble in water. | Poorly |
| When combined with a strong acid, the typical LA molecule will form a ______. | Salt |
| How are LAs manufactured in the US? | As hydrochloride salts |
| In solution, the LA salt exists between what two states? | Neutral salt (base) and ionized (cation) |
| The cation is the ______ state of an LA molecule. | Ionized |
| LAs are weak bsaes with a pKa in the _______ to _______ range. | 7, 9 |
| What is a conduction block? | Block where the LA enters sodium channels in sufficient quantity to interrupt activity |
| How great does the potential peak sodium current of each nerve cell membrane have to be in order to propagate an action potential? | 5-6x greater than necessary |
| The conduction block is (reversible/irreversible). | Reversible |
| When does impulse propagation occur? | When sodium channels are opened or activated |
| LAs prevent conduction by converting sodium channels into a/an (open/active/inactive) state. | Inactive |
| Identify 3 intermediate acting LA. | Lidocaine, procaine, mepivicaine |
| Identify 1 long acting LA. | Bupivicaine |
| How much of an unmyelinated nerve has to be covered w/a LA in order for an effect to occur? | The full circumference and length |
| Place each block in order from highest to lowest: sensory, motor, sympathetic. | Highest to lowest: sympathetic, sensory, motor |
| Place each block in order of onset from fastest to slowest: sensory, motor, sympathetic. | Fastest to slowest: sympathetic, sensory, motor |
| (Larger/Smaller) fibers take longer to block than (larger/smaller) nerve fibers. | Larger; smaller |
| A sympathetic block occurs with blockade of what types of nerve fibers? | B |
| Which fibers are the smallest and most easily blocked? | B |
| What type of nerve fibers are associated with spinal anesthesia? | All nerve fibers (B, C, and all of A and the A subgroups) |
| Which fibers are the largest in the body? | A-alpha |
| A-alpha fibers are associated with what types of blocks? | Motor |
| Where does the spinal cord end? | L1-L2 |
| The superior aspect of the iliac crest is a landmark for what level of the spine? | L3-L4 |
| Which side of the sodium channel allows for reversible binding? | Axoplasmic (intracellular) |
| LA (can/cannot) move through sodium channels from the extracellular environment. | Cannot |
| The lipid soluble portion of the LA, the benzene ring, is also known as the _______. | Base |
| The base portion of the LA is the (lipophilic/hydrophilic) section of the LA molecule. | Lipophilic |
| pH of the intracellular is more (basic/acidic). | Acidic |
| The pH of the intracellular environment favors the (basic/cationic) form of the LA. | Cationic |
| What is the best chemical state for diffusion into a neuron by a LA? | Intermediate lipid solubility |
| What two conditions slows down movement of an LA into the intracellular environment of a neuron? | Very high or low lipid solubility |
| Once inside the neuron, what form of the LA favors the sodium channel? | Cationic (ionized) |
| Alternative structures of the same protein are referred to as _______, and the transitions between them are called ________. | Conformations; conformational changes |
| What causes a conformational change of the sodium channel to allow for sodium movement into the nerve cell? | Depolarization |
| Subsequent impulses (do/do not) influence a sodium channel that has been inactivated by a LA. | Do not |
| Potency is directly proportional to _______. | Lipid solubility |
| The ability of a LA to cross a neural membrane is directly r/t its __________. | Lipid solubility |
| Any alteration of the lipid solubility of a LA alters its ________. | Potency |
| What is created from the addition of a 4-carbon aliphatic chain to the intermediate chain of procaine? | Tetracaine |
| What is created from the addition of 3 carbons to the methyl group on the tertiary amine of mepivicaine? | Bupivicaine |
| The addition of _________ prior to the injection of an LA increases the amount of (ionized/non-ionized) drug. | Sodium bicarbonate; non-ionized |
| How can the potency of an LA be increased without affecting its lipid solubility? | Increasing the non-ionized portion of the drug |
| What determines the blocking action of an LA? What determines its duration? | Blocking=ionic activity of hydrophilic portion of the LA; Duration=lipid solubility and protein binding |
| Which two LA are the most lipophilic and what is unique about them? | Bupivicaine and tetracaine; have the longest duration of action |
| What determines the speed of onset of a LA? | Location of injection |
| How do spinals and epidurals differ in onset of effect and why does this occur? | The effect of spinals occurs sooner because they are injected directly into the spinal nerves, whereas epidurals require movement of the LA across the dura to achieve anesthetic effect |
| The active form of the LA is the ________ form. | Nonionized |
| Biotransformation, deactivation, and elimination start in the ______ section of the LA. | Intermediate chain |
| Movement away from the target neural structure starts what three processes? | Deactivation, biotransformation, and elimination |
| What does the accuracy of regional anesthetic technique depend on? | The proximity of the injection to the nerve w/o intraneural injection |
| True/False: The LA that is absorbed into the bloodstream is not readily absorbed into the CNS. | False – the small molecular structure of the LA makes the nonionic form readily absorbed |
| What are five possible scenarios of CNS toxicity from LA injection? | Direct injection into the CNS with a dose intended for epidural anesthesia; cytotoxicity; intraneural injection; IM; additives creating toxicity |
| What is the purpose of a test dose in an epidural? | To gauge whether the catheter is located in the spinal canal or a blood vessel |
| All spinals have to be free of what substance? | Methylparaben |
| Identify clinical signs of toxicity with increased CNS concentrations of lidocaine. | Visual disturbances, muscular twitching, convulsions, unconsciousness, coma, respiratory arrest, CVS depression |
| Adequate ventilation in the event of lidocaine toxicity helps prevent what two conditions? | Acidosis and ion trapping |
| What two types of medications can be used to prevent or treat seizures associated w/lidocaine toxicity? | BZDs or sodium thiopental |
| True/False: Long-term sequelae are common with lidocaine toxicity. | False |
| What occurs with the most severe cases of LA toxicity? | Plasma levels of the agent causes hemodynamic instability d/t direct action on the myocardium and ANS |
| What are the CV consequences of lidocaine toxicity? | Negative inotropy, arrhythmia, cardiac arrest |
| True/False: The effects of a LA on the heart is dose and medication specific. | True |
| The effect of bupivicaine accumulation is due to what factor? | The fast movement into and slow movement out of a nerve cell |
| Toxicity of a local anesthetic may ultimately lead to depression of what system? | Depression of myocardial conduction system |
| What is the antibody of anaphylaxis? | IgE |
| What are the two classes of body responses to a foreign substance? | Systemic and cellular |
| What does systemic exposure lead to? What can repeat systemic exposure lead to? | Creates antibodies; can lead to anaphylaxis |
| What is the slow-reacting substance of anaphylaxis? | Neutrophil |
| When does cell mediated immunity occur? | With the sensitization of cells |
| A local response to exposure is often known as _________. | Contact hypersensitivity |
| Several (days/weeks/months) must pass between initial exposure to a potential allergen and the potential for anaphylaxis. | Weeks |
| What do neutrophils potentiate? | Constrictive effects of histamine on smooth muscle |
| What do the constrictive effects of histamine result in? | Bronchospasm and increased capillary permeability |
| Identify the aminoester local anesthetics and their trade names. (5) | procaine (Novacaine), chloroprocaine (Nesacaine), tetracaine (Pontocaine), cocaine, benzocaine (Cetacaine) |
| What is the trade name for procaine? | Novocaine |
| ______ is the least toxic LA. | Procaine |
| Procaine is a derivative of ______. | Para-aminobenzoic acid (PABA) |
| Why is procaine the least toxic of all LA? | Rapidly metabolized |
| What does metabolism of procaine begin with? | Exposure to plasma cholinesterase |
| What is the clinical application of procaine? | Cutaneous or mucus membrane infiltration (mostly dental practice) |
| What is the trade name for chloroprocaine? | Nesacaine |
| How is chloroprocaine metabolized? | Ester hydrolysis |
| Chloroprocaine, like procaine, is used for what purpose? | Infiltration of cutaneous or mucus membranes |
| What can occur with subarachnoid injection of chloroprocaine? | Severe neurologic injury |
| What is the trade name for tetracaine? | Pontocaine |
| What is the most popular agent for spinal anesthesia? | Tetracaine |
| Tetracaine has a (high/low) lipid solubility factor. | High |
| What is added to tetracaine to prolong its duration. | 1% solution of epinephrine |
| How much is the duration of tetracaine increased with the addition of 1% epi? | 20-30% |
| How much 1% epi is usually added to tetracaine to prolong its duration? | 80-100mg |
| What is the onset/offset profile of tetracaine? | Slow onset and long duration d/t high pKa and lipid solubility |
| Cocaine is an (ester/amide). | Ester |
| What was the first agent used for local anesthesia? | Cocaine |
| What properties lead to the abuse of cocaine? | Oral ingestion identified excitatory and euphoric properties |
| Besides local anesthesia, what other effect does cocaine have? | Intense vasoconstriction |
| The vasoconstrictive properties of cocaine make it useful for application on _______. | Mucus membranes |
| What is the max dose of cocaine for an adult? | 200mg (~3mg/kg) |
| Where is cocaine commonly used and how is it applied? | ENT; applied to mucus membranes w/sponges saturated w/4-5% sol. |
| What is the trade name for benzocaine? | Cetacaine |
| Benzocaine, like cocaine, is useful in direct application of _______. | Mucus membranes |
| Toxicity of benzocaine surfaces with amounts > ______mg. | 200-300 |
| The use of which local anesthetic can result in methemoglobinemia? | Benzocaine |
| Benzocaine is ideal for what type of anesthesia? | Topical |
| Identify the 7 aminoamide anesthetics and their trade names. | Lidocaine (Xylocaine), Mepivicaine (Carbocaine), Prilocaine (Citanest), Etidocaine (Duranest), Bupivicaine (Marcaine, Sensorcaine), Ropivicaine (Naropin), Dibucaine |
| What is the most widely used local anesthetic in the world? | Lidocaine |
| What is the trade name for lidocaine? | Xylocaine |
| What is the most widely used and most versatile of all LA? | Lidocaine |
| What is the most popular agent for infiltration? | Lidocaine |
| What does eutectic mean? | Melts quickly |
| Which LA can be nebulized into the airway? | Lidocaine |
| What reflexes can lidocaine suppress? | Hiccups and cough |
| What preservative contributes to the allergy profile of lidocaine? | Methylparaben |
| What is the test dose of lidocaine used to r/o intravascular injection? | 3cc MPF 2% lidocaine w/epi 1:200,000 |
| Which LA is associated with cauda equina syndrome? | Lidocaine |
| How is lidocaine used in obstetrics? | Spinals for C-sections |
| *BONUS* What is the cauda equina? | Bundle of spinal nerves and nerve roots, consisting of the 2-5 lumbar, 1-5 sacral, and the coccygeal nerves. |
| *BONUS* What does the cauda equina innervate? | Pelvic organs and lower limbs |
| *BONUS* The termination of the spinal cord is known as the ______. | Conus medullaris |
| What is cauda equina syndrome? | Serious neurologic condition w/acute loss of function of the lumbar plexus |
| Cauda equina syndrome may be a result of anesthesia in what conditions? | Iatrogenic lumbar punctures, catheter trauma from spinals, high local anesthetic concentrations around the cauda equina |
| What is the trade name for mepivicaine? | Carbocaine |
| Which local anesthetic has properties comparable to lidocaine? | Mepivicaine |
| What is a unique property of mepivicaine? | Diffuses through tissues proximate to the site of injection |
| The unique property of mepivicaine makes it ideal for what application? | Field blocks |
| What is the ideal LA for field blocks? | Mepivicaine |
| The application to clinical practice for mepivicaine is in ________ anesthesia. | Infiltration |
| What other applications, besides infiltration anesthesia, is mepivicaine used in? | Spinals and epidurals |
| What is the trade name for prilocaine? | Citanest |
| Which amide has been associated w/methemoglobinemia? | Prilocaine |
| Which LA is a common alternative to lidocaine? | Prilocaine |
| Prilocaine is not used in which application of anesthesia? | Spinals |
| Prilocaine acts in a manner similar to _______. | Lidocaine |
| What is the trade name for etidocaine? | Duranest |
| What is etidocaine derived from? | Lidocaine |
| How does etidocaine compare to lidocaine? | More potent and longer acting |
| The increased lipid solubility of etidocaine also makes it ____ and ____. | Potent; toxic |
| Which LA is used for topical anesthesia, with application to the cornea and trachea? | Etidocaine |
| Like prilocaine, etidocaine is not used in what aspect of anesthesia? | Spinals |
| What are the two trade names for bupivicaine? | Marcaine, Sensorcaine |
| Which LA is the most cardiotoxic? | Bupivicaine |
| Bupivicaine is a LA used for when a (long/short) duration of analgesia is important. | Long |
| Bupivicaine is used in spinals with (hypo/hyper)baric techniques. | Hyper |
| When is bupivicaine used in anesthesia? | Effect with long-duration sensory anesthesia, spinals (hyperbaric), epidurals, nerve blocks |
| What is the trade name of ropivicaine? | Naropin |
| Ropivicaine is chemically similar to which local anesthetics? | Bupivicaine and mepivicaine |
| Which medication is the replacement LA for bupivicaine? | Ropivicaine |
| Which is safer in regards to cardiotoxic effects: bupivicaine or ropivicaine? | Ropivicaine |
| Ropivicaine has a (high/low) level of potency and lipid solubility. | High |
| What is the replacement medication for bupivicaine? | Ropivicaine |
| In what clinical applications is ropivicaine used? | Infiltration and epidural anesthesia |
| Which LA has a high affinity for plasma cholinesterase? | Dibucaine |
| Dibucaine inhibitis up to _____% of plasma cholinesterase activity in its normal genetic form, and as little as _____% of the atypical variants. | 80; 15 |
| Provide the dibucaine numbers for normal, heterozygous, and homozygous forms of plasma cholinesterase expression. | Normal=80%, heterozygous=50-60%, Homozygous=10-20% |
| Which 5 local anesthetics are most commonly used in anesthesia? | Lidocaine, mepivicaine, bupivicaine, ropivicaine, tetracaine (per Joseph) |
| *BONUS* Which two LA are beneficial in topical anesthesia? | Tetracaine, lidocaine |
| *BONUS* Which LA is not used for local infiltration? | Tetracaine |
| *BONUS* Tetracaine is used in what two anesthetic applications? | Topical and spinal anesthesia |
| *BONUS* Lidocaine can be used in any aspect of regional anesthesia. | True |
| *BONUS* What are three regional applications of procaine? | Infiltration, nerve block, spinals |
| *BONUS* Chloroprocaine, like procaine, can be used for infiltration and nerve blocks but where does it differ from procaine? | Ok for epidurals and not for spinals |
| *BONUS* True/False: All of the aminoamide anesthetics can be used in epidural anesthesia as well as nerve blocks. | True |
| *BONUS* Which two aminoamides can be used for spinal anesthesia? | Lidocaine, bupivicaine |
| *BONUS* What two LA can be used for IV regional anesthesia? | Lidocaine, prilocaine |
| What three solutions serve to increase the speed of onset of LAs? | Dextran, carbonate, bicarbonate |
| How does the addition of dextran influence LA? | Increases speed of onset and depth of the conduction block |
| The addition of carbonate to a LA has (variable/consistent) outcomes. | Variable—carbonation is rarely seen today |
| How does bicarbonate influence the LA? | Speeds the onset of the conduction block |
| What benefits does epinephrine have as an additive to a LA? | Prolongs duration, marker for intravascular injection, decreases blood loss |
| What is a field block? | Block where the LA is infiltrated around the border of the surgical field, leaving the operative area undisturbed |
| What is a nerve block? | Block where the LA is injected directly adjacent to the nerve supplying the surgical field |
| Name the 5 aminoamide anesthetics along with their plain dose max 24hr totals. | Lidocaine 300mg, mepivicaine 300mg, prilocaine 500mg, bupivicaine 175mg, ropivicaine 250mg |
| Name the 5 aminoamide anesthetics along with their epi dose max 24hr totals. | Lidocaine 500mg, mepivicaine 500mg, prilocaine 600mg, bupivicaine 225mg, ropivicaine 300mg |
Created by:
philip.truong
Popular Nursing sets