Term
| What determines the efficacy of local anesthetics? |
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Definition
| Hydrophobicity: drug must get into the cell before it can act on the sodium receptor. |
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Term
| What hydrophobicity is most ideal for local anesthetics?...Mild, moderate, or highly? |
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Definition
|
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Term
| Where is the binding site for local anesthetics? |
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Definition
| Intracellular portion of sodium channel |
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Term
| What determines the onset and potency of local anesthetics? |
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Definition
| the amino protion of the durg and extracellular pH |
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Term
| How does pH effect potency of local anesthetics? |
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Definition
| The lower the pH the more potent |
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Term
| What determines duratino of action of local anethetics? Which bond hydrolizes faster? |
|
Definition
| Whether it is an ester or amide bond. Ester |
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Term
| What metabolizes aminoesters? |
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Definition
|
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Term
| What metabolizes aminoamides? |
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Definition
|
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Term
| What are the 4 conformation of voltage-gated Na+ channels? |
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Definition
| Inactive, open, closed, resting |
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Term
| At normal resting potential the majority of Na+ receptors are in which state? |
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Definition
|
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Term
| Which receptor state is help by local anesthetics? |
|
Definition
| inactivated conformation mostly (but also closed and open…RESTING conformaiton so almost no affinity for drug) |
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|
Term
| What is tonic inhibition? Where is it found? What is is action? |
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Definition
| Fixed ration of Na+ channels are blocked at all times. Found in inactive tissues. Minimizes blockade of non-pain sensory modalities. |
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Term
| What is phasic inhibition? Where is it found? What is its action? |
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Definition
| degree of inhibiotn increases with rate of action potentials. Found in tissues undergoing high frequency stimulation. Maximizes selective inhibiton of pain transmission. |
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Term
| What is a major challenge for application of local anesthetics? |
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Definition
| Must diffuse through epineurium, Perineurium, and endoneurium. (perineurium is most difficult) |
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|
Term
| What is the order of senstivity to local anesthetics? |
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Definition
| A delta, C fibers, Temp, touch, proprio, skeletal muscle tone, and voluntary muscle movement) |
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Term
| What is placed in wounds before sutureing? |
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Definition
| TAC (tetracaine, epinephrine, cocaine) |
|
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Term
| What is the MOA of Epinephrine in TAC? |
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Definition
| Vasodilator so local stays local. |
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Term
|
Definition
| Tetracain, epi, cocain…used before suturing small wounds and cuts |
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Term
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Definition
| topical and injected anesthetic |
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Term
|
Definition
|
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Term
| Wheich topical anesthetics are first choice and why? |
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Definition
| Lidocaine and benzocaine. They are insoluble in water and not absorbed well |
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Term
| Least vasodilating injected anesthetic? |
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Definition
|
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Term
| What anesthetic is used in pediatric dentistry? |
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Definition
|
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Term
| Which injectible anesthetic has the longest half life? |
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Definition
|
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Term
| Which injectible anesthetic is used for lenghty procedures and post-op pain? |
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Definition
|
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Term
| Which injectied anesthetic has a low frequency of allergic rxn? |
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Definition
|
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Term
| What drugs are used for infiltration anesthesia? |
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Definition
| Lidocaine, procaine and bupivacaine |
|
|
Term
| Peripheral nerve blocks are injected where? |
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Definition
|
|
Term
| Central nerve blockates include? |
|
Definition
| Epidurals and intrathecal anesthesia |
|
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Term
| What anesthetic is useful in epidurals? What is its side effect? |
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Definition
| Bupivacaine. May cause cardiotoxicity |
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Term
| What druts may be safer in epidurals? |
|
Definition
| Ropivocain and levobupivacaine |
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Term
| What is required with intravenouse regional anesthesia? What are its advantages? Disadvantage? |
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Definition
| Tourniquets. Bloodless surgery and simplicity of method. Practical time limit on its use. |
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Term
| What drug is preferred for intravenous regional anesthesia? Which is not advisable? |
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Definition
|
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Term
| What kind of drug is procaine? Clinical use? |
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Definition
| Short-acting aminoester. Infiltration anesthesia and dental procedures (primary use) |
|
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Term
| What analog of procain is used in obsetrics? |
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Definition
|
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Term
| What metabolite of procaine acts as an allergen and interferes with sulfonamide drugs? |
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Definition
|
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Term
| What kind of drug is tetracain? When is it used? |
|
Definition
| Long-acting aminoester. Spinal and topical anestesia |
|
|
Term
| What limits the use of cocaine? |
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Definition
| Cardiotoxicity and euphoria |
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Term
|
Definition
| ophthalmic anesthesia and in TAC |
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|
Term
| What kind of drug is Lidocaine? Adverse effects? |
|
Definition
| Aminoamide. Drowsiness, tinnitus, twitching, seizures |
|
|
Term
| Prilocaine is similar to lidocaine but also exhitis? |
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Definition
|
|
Term
| What kind of drug is Bupivacaine? Adverse effects? Selective for? |
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Definition
| Long-acting aminoamide. Cardiotxicity. Nociceptors |
|
|
Term
|
Definition
| Similar to bupivacaine but with less carditoxicity |
|
|
Term
|
Definition
| Sturctural homolog to bupivacaine |
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|
Term
| What is unique about Articaine? |
|
Definition
| Aminoamide with ester bond and metablolized in both plasma and liver |
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|
Term
|
Definition
| Lidocaine and prilocaine cream patch for topical anestesia |
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|
Term
|
Definition
| Venipunctures and replaces TAC |
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|
Term
| What are the major toxicities of local anestethics? |
|
Definition
| 1. local irritation 2. biphasic effects on vascular and bronchaial smooth muscle 3. decrease cardiac contractitily 4. cross BBB and escite CNS 5. Hypersensitivity (dermatitis, asthema) |
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