question

What are the five general routes for the application of local anesthetic agents?

answer

a) Topical, by creams, patches, sprays, or lozenges b) Infiltration, by direct intradermal or subcutaneous injection into the tissue near the area of operation. c) Nerve block, by injection near a bundle of nerves (a "sensory nerve trunk"), to induce anesthetic and relieve pain or spasms along several nerve pathways e) Spinal, by direct injection into the subarachnoid space cerebral spinal fluid (CSF) in the lumbar area, to induce anesthesia in the nerve roots of the body's complete lower trunk. The density of the solution and the position of the patient affect the diffusion of the anesthetic. f) Epidural, by injection into the epidural space of the spinal column, primarily for anesthesia for labor and delivery; takes a relatively large amount of anesthetic to diffuse across the localized area.

question

What is the mechanism of action for local anesthetics? Which electrolyte is involved?

answer

Local anesthetics bind to receptors near the sodium channel on the nerve membrane. As the amount of the local anesthetic accumulates, the sodium channels become obstructed. Impulses along the nerve slowed, the strength and propagation of the action potential are diminished, and communication along the fiber is blocked.

question

What is the numeric value of physiological pH? Is it basic acidic or neutral?

answer

7.4; Basic

question

Why is a local anesthetic less effective in the presence of inflammation?

answer

An oral infection with the accompanying inflammation can therefore, create a reduction in pH, which in turn can cause a local anesthetic to develop a charge, become polarized, and have diminished tissue penetration.

question

What is the purpose of adding epinephrine to a local anesthetic?

answer

The addition of epinephrine not only minimizes the vasodilation caused by the local anesthetic agent, but causes vasoconstriction of the blood vessels in the area surrounding the injection. The vasoconstriction decreases perfusion of blood to the region, and the local anesthetic is not carried away.

question

Which local anesthetic causes vasoconstriction without the addition of epinephrine? What is its historical significance?

answer

Novocaine; Historically, the esters represent the first collection of local anesthetic agents. They are more prone to cause allergic reactions among patients.

question

Which patient population is most prone to problems when sulfites are used as preservatives?

answer

Patients with asthma are susceptible to sulfites known to cause bronchospasm.

question

Which patient population is more likely to have excessive capillary constriction and tissue damage when epinephrine is used?

answer

Diabetes patients

question

How many milligrams of epinephrine are contained in a 1.8mL cartridge when the stated dilution of epinephrine is 1:200,000?

answer

0.009mg

question

How many milligrams of lidocaine are contained in a 1.8mL cartridge when the stated concentration is 2%.

answer

36mg.

question

What are the two general categories of local anesthetics? Do cross-over allergies between these categories exist? Which category is more prone to allergic reactions?

answer

1- Esters 2- Amides these two categories do not have any cross-over effect between them; however, esters have a cross-over effect within the ester category. For example: A patient having an allergy to one ester-type anesthetic will probably have a cross-over allergy to other states.

question

Which category is based on PABA? How are local anesthetics in this category metabolized?

answer

With the exception of cocaine, the local anesthetics of the ester class are all derivatives of para- aminobenzoic acid (PABA). The ester linkage is primarily hydrolyzed by plasma cholinesterase before going through further metabolism by the liver. The esters are excreted by the kidneys, nearly all as metabolites.

question

The sulfonamide class of antibiotic's can have a drug interaction with which category of local anesthetics?

answer

Ester-type anesthetics

question

A red flag should fly up when a patient states he is allergic "to Novocain" Why?

answer

Because patients often confuse panic reactions with allergies. When the patient describes his allergy as "palpitations," "cold perspirations," or even (fainting," chances are it's a panic reaction.

question

Lidocaine is a prototype drug in which local anesthetics category?

answer

Amide class

question

What drug allergy is a specific contraindication to the use of articaine?

answer

Patients with allergy to sulfur drugs.

question

What is the name of a "natural" analgesic and anesthetics?

answer

Eugenol (oil of cloves) is use for topical application of clove oil depresses the function of sensory receptors by a powerful inhibition of prostaglandin biosynthesis. When applied topically, it causes local anesthetics and analgesia to the oral mucosa and in post-extraction alveolitis (dry socket).

question

What is the name of an alternative anesthetic when a patient is allergic to drugs in the primary two categories?

answer

Anesthesia can be used by using diphenhydramine (Benadryl) injection.

question

Which reflex may be blocked by the use of lidocaine as a topical anesthetic? Why is this a concern?

answer

The "gag reflex" can be blocked. This is a concern because if lidocaine is gargled, the body's natural reflex is to prevent inhaling, or aspiration, fluids and mucous into the lungs can be hindered.

question

What is the best way to store local anesthetics agents?

answer

(1) Place the date of the first entry into the bottle (2) Note the number of times the viral has been used (3) Place a time limit on using the multiple-dose vial. (6-9 mths can be a guide)

question

The (an) in anesthesia means what?

answer

without

question

Esthesia in anesthesia means what?

answer

sensation

question

1853: He was the first to permit the injection of small, measured volumes.

answer

Alexander Wood's

question

1856: He proposed use of coco leaves as an anesthetic

answer

Samuel Percy

question

What was the antiseptic used clinically?

answer

Lidocaine, 1948

question

What are the uses of Local anesthetics in dentistry

answer

extractions, apical surgery, cyst removal, restorations, simple incise and drain

question

What are the five routes of administration for using local anesthetics

answer

Topical, Infiltration, nerve block, spinal, epidural

question

Topical anesthetic includes

answer

creams, patches, sprays, lozenges

question

Infiltration anesthetic is what

answer

Subcutaneous or intradermal injection near area of operation, usually maxilla, in areas of infection, occasionally in mandibule.

question

Nerve block anesthetic is what

answer

injection near a sensory trunk, serveral nerve pathways such as alveolar nerve, long buccal nerve, mental nerve

question

spinal anesthetic is what

answer

into the sub arachnoid space of spinal column

question

epidural does what as an anesthetic

answer

into the epidural space of the spinal column (labor and delivery)

question

When impulses are generated by changes in the nerve's membrane permeability Sodium ions inflow across the nerve membrane causing what reaction?

answer

Action potential

question

Action potential does what

answer

relays information along the nerve so there is communication between the Peripheral Nervous System and the CNS

question

What happens to make anesthesia occur

answer

When the action potential is restricted the communication is blocked and if enough nerve is affected that is the anesthesia occurs.

question

In its simplest terms where does local anesthetics bind?

answer

binds to receptors near the sodium channel on the nerve membrane

question

As the amount of the local anesthetic accumulates, the sodium channels become obstructed the what happens

answer

Impulses along the nerve are slowed, the strength and propagation of the action potential are diminished and communication along the fiber is blocked.

question

pH is a measure of what

answer

acid, base

question

what is the pH that neutral

answer

7

question

pH over 7 is what

answer

basic

question

pH under 7 is what

answer

acidic

question

Physiological pH is what and what does it mean

answer

7.4, meaning the body is slightly basic

question

nonpolar charge are these with

answer

a negative charge

question

non polar drugs have no charge this means that they are more

answer

lipophilic

question

non polar drugs are those that do not have a charge, they are more readily

answer

absorbed by tissues

question

If the environment into which a drug is deposited is altered, the drug may develop a

answer

charge

question

Most local anesthetics are _______bases.

answer

weak

question

The mechanism of action of local anesthetics is to

answer

block nerve conduction by preventing nerve depolarization

question

Local anesthetics produce their primary effects by

answer

blocking nerve conduction

question

Local anesthetics exert their action by

answer

interfering with the flow of sodium across neural membranes

question

An infection in an area can prevent the accumulation of effective concentrations of local anesthetic solution because of

answer

low tissue pH.

question

Patches anesthetics work best when the are applied

answer

on dried areas to soft tissues and to regaines that are not thickened by repeated use

question

spray anesthetic have several limitations because

answer

difficult to control on small area, sufficient amounts could be inhaled to cause a toxic reactions

question

Absorption across a mucous membrane is hampered due to the poor buffering nature of the tissue, meaning

answer

the mucosa environment can possess a pH as low as 5.5

question

What are the best ways to prevent a toxic reaction from the administration of a local anesthetic is to

answer

being safe with family history, aspirate the syringe (draw back to make sure the capsule is fully engaged,

question

What is a couple of reasons that local anesthetics help people

answer

It is very safe, fear is lessened

question

What are some challenges in using local anesthetics

answer

Allergies to specific agents may emerge, vials contain preservatives known as (methylparaben, sulfites). Novacain which needs to be distinguished between allergies and anic reactions, syncope, side effects, etc.

question

What are the best ways to prevent a toxic reaction from the administration of a local anesthetic

answer

through medical history, aspiration (make sure the syringe is fully engaged), use the least amount needed to reduce potential sensitivities or allergies, inject slowly, repeated injection in the same can cause vasoconstriction with epi., wait for the anes. to work, avoid infection/inflamed areas

question

what causes an increased perfusion of blood to the injected area

answer

vasodilation

question

what happens when vasodilation happens in ansthetics

answer

(1) the drug is being carried away (less effective), (2) anesthetic reaches the cardiac muscle with the potential for undesired myocardial effects.

question

What is used in medical emergencies to decrease ventricular arrhythmias

answer

Lidocaine

question

Patients with ____are predisposed to problems with capillary circulation. They may experience an increase in tissue damage.

answer

diabetes

question

what is add is added to anesthetics in order to maintain effective concentrations of at the injection site

answer

epinephrine

question

The ______decreases perfusion of blood to the region, and the local anesthetic is not carried away.

answer

vasoconstriction

question

Epinephrine added to local anesthetics is expressed in terms of dilution, what are the dilution examples

answer

1:100,000 and 1:200,000, 1 gram per 100,000 or 1 gram per 200,000 1000mg/100,000ml 1mg/100ml so in 1.8ml of solution of local anesthetic there are .018mg of epinephine

question

What is the oldest in the classification of anesthetics

answer

Esters

question

what is the generic of Procaine: gets confusing when patients say they are allergic, hasn't been used in years

answer

Novacaine

question

What is the action of epinephrine when combined with local anesthetic is to

answer

increase the duration of anesthetic

question

What are the two classes of local anesthetics

answer

Esters and Amides

question

A patient having an allergy to one of the ester-type anesthetics will probably have

answer

a cross-over allergy to other esters.

question

What are the drugs in the Ester class

answer

Procaine (novocaine) short half-life, Chloroprocaine (Nesacaine) short half-life, Propoxycaine, Tetracaine, Benzocaine

question

Despite its greater notoriety as a drug of abuse____is an excellent topical local anesthetic and can be legally prescribed

answer

cocaine

question

What are local anesthetics

answer

Procaine- (Novacaine) short-half-life Chloroprocaine (Nesacaine) Propoxycaine- potent and toxic Tetracaine- topical Benzocaine- can sensitize pt's to all esters

question

What NS does cocaine stimulate that others anesthetics does not.

answer

sympathetic

question

The amide class of local anesthetics agents are metabolized where?

answer

in liver & excreted by the kidneys

question

Why does cocaine work (by what addition)

answer

addition caused by dopamine accumulation which affects brain pleasure centers by cocaine blocking uptake of dopamine.

question

Where are the Amides local anesthetics derived from?

answer

the dye aniline

question

What are the routes for anesthetics

answer

topical: creams, patches, sprays infiltration: direct intradermal or subcutaeous nerve block: injection near bundle of nerves spinal: direct into cerebral spinal fluid (CSF) epidural: epidural space of spine: delveries

question

What is the pH above and below 7

answer

7 is netrual, below is acidic and above is basic

question

When a drug develops electrical charge, its considered___this makes it become less____.

answer

polarized, lipophilic

question

What type of activity gives physiological pH the ability to have adequate penentration?

answer

lipophilic

question

Epinephrine added to local anesthetics is expressed in what terms

answer

1:100,000 ml= .018mg of epinephrine

question

What is the oldest classification of local anesthetics

answer

Esters

question

The prototype agent in the Amides class is

answer

lidocaine

question

An acidic environment is

answer

7 or below

question

What are the ways that you can prevent toxic reactions from local anesthetics

answer

1- through medical hx 2-aspiration- make sure that the carpule is fully engaged. 3- Use least amount: reduce potential sensitivities or allergies 4- Inject slowly 5-Repeated injection in same area causes vasoconstriction 6- wait for anesthetic to work 7- avoid repeated injunction in same area/ inflamed area.

question

What are the topical anes. forms

answer

patches-best used dry sprays- difficult to control

question

The action potential relays information along the nerve so there is communication between the PNS and ____

answer

CNS. Action potentials are diminished and communication between the PNS and the CNS is blocked causing the anesthetic to work.

question

Sodium ions inflow across the nerve membrane causing an ______.

answer

action potential.

question

What are the toxicity/challenges in using local anesthetics

answer

-Very safe -people fear injections -allergies (methylparaben, sulfides)

question

Local anesthetics should easily

answer

bn

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