Lab Manual: LA General

Question 1

What topical Anesthesia is used to prior to injections?

Answer 1

Benzocaine 20%

Question 2

What is the chemical structure of Benzocaine

Answer 2

Ester

Question 3

What needs to be done to the tissue before applying the benzocaine?

Answer 3

Area must be dry

Question 4

What is the general chemical structure of an LA molecule?

Answer 4

Aromatic group + Intermediate Chain + Amine Group

Question 5

What are the two possibilities for the intermediate chain portion of the LA molecule?

Answer 5

Amines or Esters

Question 6

Where are ester LA’s metabolized?

Answer 6

In the plasma

Question 7

Where are amine LA’s metabolized?

Answer 7

In the Liver

Question 8

What is the % and parts epi for Lidocaine?

Answer 8

2%

1:100,000 epi

Question 9

What are the 3 brand names for Lidocaine 2%

Answer 9

Xylocaine
Octocaine
Lignospan

Question 10

What is the MRD for Lidocaine 2%

Answer 10

4.4 mg/kg

Question 11

How many pounds are in 1 kg?

Answer 11

2.2 lbs/kg

Question 12

How many kgs are in 1 lbs?

Answer 12

0.454 kg/lb

Question 13

Calculate the MRD of lidocaine for a 186 pound patient

Answer 13

186 * .454 = 84.444 kgs * 4.4 mg/kg = 371.5 mg Lidocaine

Question 14

What is the Specific Receptor Theory in terms of a LA’s mechanism of Action?

Answer 14

LA works by binding to receptor sites within sodium channels preventing nerve depolarization and conduction

Question 15

What is the most common % and epi ratio for Prilocaine?

Answer 15

4%

1:200,000 epi

Question 16

What is the brand name of Prilocaine?

Answer 16

Citanest

Question 17

What is the expected onset time of Citanest/Prilocaine?

Answer 17

Fast, 2-4 mins

Question 18

What is the duration of Citanest/Prilocaine?

Answer 18

Short to Intermediate

Question 19

What is the MRD for Citanest/Prilocaine?

Answer 19

6 mg/kg

Question 20

What is a possibility with Citanest/Prilocaine to look out for?

Answer 20

Persistent parathesia

Question 21

When is Prilocaine/Citanest the least painful?

Answer 21

When it is used without epi

Question 22

What is the common % and epi ratio for Articaine?

Answer 22

4%

1:100,000

Question 23

What is the brand name for Articaine?

Answer 23

Septocaine

Question 24

What is the MRD for Septocaine/Articaine?

Answer 24

7 mg/kg

Question 25

What is the expected duration for Septocaine/Articaine

Answer 25

Intermediate

Question 26

What block can you never use Articaine/Septocaine for?

Answer 26

IAN

Question 27

What can Articaine/Septocaine use on the IAN cause?

Answer 27

Neurotoxicity

Question 28

In general "i+caines" are

Answer 28

amide LA's

Question 29

What is the common % and epi ratio for Mepivacaine?

Answer 29

3% | No vasoconstrictor used

Question 30

What are the 3 common brand names for Mepivacaine?

Answer 30

Carbocaine Polocaine Scandonest

Question 31

What patients are typically prescribed Mepivacaine?

Answer 31

Cardiac pts | Epi sensitive patients

Question 32

What is the trade off for Mepivacaine's lack of epinephrine?

Answer 32

Short duration | Less profound anesthesia

Question 33

What is the % and epi ratio for Bupivacaine?

Answer 33

0. 5% | 1: 200,000

Question 34

When is Bupivacaine used?

Answer 34

Long duration surgery | Acute pain

Question 35

What is the MRD for Bupivacaine?

Answer 35

90 mg (10 carpules)

Question 36

What is the brand name for Bupivacaine?

Answer 36

Marcaine

Question 37

What is an additional antioxidant vasoconstrictor sometimes used as an injection additive?

Answer 37

Sodium metabisulfite

Question 38

What additive is an allergen and a preservative?

Answer 38

Methyparaben

Question 39

How many mLs of solution are in each carpule?

Answer 39

1.8 mL

Question 40

How much LA is in 1 carpule for 2%, 3%, 4%, and 0.5% solutions?

Answer 40

``` 2% = 36 mg 3% = 54 4% = 72 .5% = 9 mg ```

Question 41

How much epi is in 1 carpule for 1:100k and 1:200k?

Answer 41

1: 100 = 0.018 mg 1: 200 = 0.009 mg

Question 42

What is the MRD of epi for a healthy patient?

Answer 42

.20 mg or about 10 carpules

Question 43

What is the MRD of epi for a cardiac patient?

Answer 43

.04 mg or about 2 carpules

Question 44

What is the widest gauge of needle?

Answer 44

Red = 25

Question 45

What is the narrowest gauge of needle?

Answer 45

Blue = 30

Question 46

What is the middle gauge of needle?

Answer 46

Yellow = 27

Question 47

What is the expected time of onset for the maxilla?

Answer 47

3-5 minutes

Question 48

What is the expected time of onset for the mandible?

Answer 48

3-5 minutes | 7-10 minutes for a block

Question 49

How does inflammation effect the LA's effectiveness?

Answer 49

Inflamed tissue is more acidic so more of the solution is in its cationic form which cannot penetrate the membrane of the neuron so it is less effective

Question 50

Which drugs should you avoid epi with?

Answer 50

Tricyclic Antidepressants Non-selective Beta Blockers Cocaine

Question 51

What condition must you avoid Prilocaine with?

Answer 51

Methemoglobinemia

Question 52

How do you treat Trismus?

Answer 52

Alternating hot/cold NSAIDs Rest

Question 53

What causes a hematoma?

Answer 53

Nicking vessels | Tx: Moist heat and Abx if needed

Question 54

How can you avoid an intravascular injection?

Answer 54

Aspirating the needle

Question 55

What are the symptoms of a needle tract infection?

Answer 55

Delayed onset of fever, chills, tenderness | Tx: Abx

Question 56

What LA is the most common cause of Persistent Anesthsia?

Answer 56

Articaine blocks