The Armamentarium

Question 1

what is the armamentarium of local anesthesia delivery system

Answer 1

syringe + needle + cartridge = delivery vehicle

Question 2

what are the types of syringes

Answer 2

• non disposable syringes
• disposable syringes
• safety syringes
• computer controlled local anesthetic delivery system

Question 3

what is breech loading

Answer 3

carpule loaded from side

Question 4

what causes blood in cartridge

Answer 4

negative pressure

Question 5

what does positive pressure cause

Answer 5

thumb ring forced solution through needle to patient

Question 6

when is pressure syringe used

Answer 6

pulpal anesthesia of one isolated tooth in the mandibular arch

Question 7

what is a jet injector

Answer 7

• liquids forced through very small openings caleld jets at very high pressure can penetrate intact skin or mucous membranes

Question 8

what is primary use for jet injector

Answer 8

topical anesthesia before needle insertion but you still need to do nerve block and infiltration

Question 9

advatnages and disadvantages to disposable syringr

Answer 9

-A: disposable, single use. sterile. lightweight.
-D: does not take prefilled dental cartridges. difficult aspiration- need 2 hands

Question 10

how should you care for needle instrument

Answer 10

• wash syringe after each use
• lubricate every 5 autoclaves
• clean harpoon with brush after each use
• replace piston and harpoon

Question 11

what are the parts of the needle

Answer 11

-bevel
- shaft
- the hub
- cartridge penetrating end

Question 12

what are the factors of the shaft

Answer 12

-diameter/guage
- length from tip to hub

Question 13

the greater angle the bevel, the greater the degree of:

Answer 13

deflection

Question 14

the smaller the guage number, the ____ the diameter

Answer 14

greater

Question 15

advantages of larger gauge needle

Answer 15

• less deflection
• greater accuracy in injection
• less change breakage
• greater aspiration
• no difference in patient comfort

Question 16

what gauges are each color needle: red, yellow and blue

Answer 16

-red: 25
- yellow- 27- what we use
- blue: 30

Question 17

where is the nondeflecting needle tip

Answer 17

in the center of the shaft

Question 18

what is the average short needle

Answer 18

20 mm

Question 19

what is the average long needle

Answer 19

32mm

Question 20

where is the weakest portion of the needle

Answer 20

at the hub

Question 21

how should the needle be handled

Answer 21

• never used on more than 1 patient
• change after 3 or more tissue penetration
• cover in protective sheath when not in use
• scoop technique

Question 22

what are the most common bent needle procedures

Answer 22

• inferior alveolar nerve block
• posterior superior alveolar nerve block
• intrapulpal injection
• PDL injection and intraosseous injection

Question 23

what would cause pain on insertion

Answer 23

dull needle

Question 24

do not bend needle if to be inserted into ____mm soft tissue depth

Answer 24

> 5mm

Question 25

how much can a cartridge hold

Answer 25

2ml solution but US cartridges hold 1.8ml

Question 26

what is the cartridge made of

Answer 26

glass

Question 27

what is the stopper (plunger)

Answer 27

receives the harpoon of the aspirating syringe

Question 28

what does gold around cylinder mean

Answer 28

articaine

Question 29

what does red around the cylinder mean

Answer 29

lidocaine with epi

Question 30

what is the diaphragm of the cartridge

Answer 30

- semipermeable membrane - where the needle penetrates into the cartridge

Question 31

what does the mylar plastic label wrap around glass cylinder do

Answer 31

protect doctor and patient in event of glass crack or shattering

Question 32

what are the cartridge contents

Answer 32

- may have vasopressor - NaCl - distilled water - methylparaben

Question 33

what is the vasopressor

Answer 33

sodium bisulfite - sodium bisulfite oxidize

Question 34

what are the problems with the cartridge

Answer 34

- bubble in the cartridge- usually nitrogen gas - extruded stopper - corroded cap- if immersed in disinfecting solution - rust on cap - leakage during injection - broken cartridge - burning on injection

Question 35

what can cause burning on injection

Answer 35

pH, alcohol, heat, expiration date

Question 36

what are the topical anesthetics

Answer 36

-betadine - chlorhexidine

Question 37

what are the most common psychogenic reactions

Answer 37

- vasodepressor syncope - hyperventilation

Question 38

what are other common induced reactions

Answer 38

- tonic clonic convulsions - bronchospasms - angina pectoris

Question 39

what do you avoid with bleeding problems

Answer 39

avoid techniques with increased chance of aspiration

Question 40

what would heart failure cause

Answer 40

- CHF (ASA III or ASA IV) may cause decreased liver perfusion -> increased t 1/2 amide local anesthesia

Question 41

what does AIDS, hepatitis, A, A and jaundice cause

Answer 41

increased t 1/2 amide

Question 42

what can be the causes of seizures

Answer 42

- stress/anxiety - hypoglycemia - hyperventilation

Question 43

when is local anesthesia contraindicated in pregnancy

Answer 43

during 1st trimester

Question 44

what does cimetidine cause

Answer 44

- increase t 1/2 of circulating local anesthesia - H2 receptor blocker compete with lidocaine for hepatic oxidative enzyme - cimetidine + ASA III CHF = relative contraindication for amide local anesthesia

Question 45

what do tricyclic antidepressants do (TCAs)

Answer 45

- enhance cardiovascular action to exogenously administered vasopressors - 5-10x increase with levonordefrin and nore-epi - 2x increase with epinephrine

Question 46

what does cocaine stimulate

Answer 46

nore-epi release and inihbit reuptake - tachycardia/ hypertension -> increase myocardio O2 requirement -> cardiac ischemia -> MI - 72 houes needed for cocaine clearance

Question 47

what are relative contraindications with local anesthesia

Answer 47

-malignant hyperthermia - methemoglobinemia