Unit 4: Uses of LA

Question 1

what are the uses of LA

Answer 1

Topical​

Local Infiltration​

Peripheral N. Block​

Intravenous​

Epidural ​

Spinal​

Tumescent Liposuction​

Question 2

the max amount of lidocaine plain is ____

Answer 2

300mg

Question 3

the max amount of lidocaine with epi is ____

Answer 3

500

Question 4

112.5 mgs of Bupivacaine with Epi and 250 mgs of Lidocaine with Epi were both given during a plastic surgery case. ​

​

What are the percentages of each local anesthetic based on the recommended maximum single dose in mgs?​

Answer 4

you gave 50% of the max of epi and bup

which is 100% of the max

Question 5

Where can you do topical anesthesia?

Answer 5

Applicable on the mucous membranes of the nose, mouth, tracheobronchial tree, esophagus, or GU tract. ​

Question 6

cocaine is ___ ____ as a topical anesthetic than tetracaine and lidocaine

Answer 6

more effective

Question 7

inhalation of lidocaine does not alter airway resistance

T or F

Answer 7

T

Question 8

Procaine and Chloroprocaine are _____ as topical anesthetics​

Answer 8

ineffective

Question 9

EMLA is composed of ….

Answer 9

Lidocaine 2.5% and Prilocaine 2.5% = 5% LA​

Question 10

dose of EMLA is

Answer 10

Dose: 1 to 2 gms/ 10 cm2 area​

Question 11

EMLA
Readiness: ____ minutes OOA​

Answer 11

45 min

2 hours​: Skin grafting​

10 minutes​
Cautery of genital warts​

Venipuncture, lumbar puncture​

Arterial cannulation (Nitroglycerine)​

Myringotomy​

Question 12

EMLA is contraindicated with _____ allergies

Answer 12

amide

Question 13

EMLA can cause ___ because it contains prilocaine

Answer 13

methemoglobinemia

Question 14

Epi is contraindicated in ____ anesthesia of end arteries

Answer 14

local infiltration

end arteries: ears, toes, nose, penis

Question 15

Local infiltration is _____ placement of LA

Answer 15

extravascular

SubQ

Question 16

peripheral NB is achieved by

Answer 16

LA injection into tissues surrounding individual peripheral nerves or nerve plexuses. ​

Question 17

MOA of peripheral NB

Answer 17

MOA: diffusion from outer mantle to central core of nerve along a concentration gradient.​​

Question 18

Which is affected first in a PNB, proximal or distal?

Which sensation will come back first, proximal or distal?

Answer 18

S/SX: proximal affected first and then distal.​
@End: proximal comes back first & then distal.​

Question 19

With PNB the Smallest ___ and ____ fibers with numb first, and then larger ____ and _____ axons.​

Answer 19

*** Smallest sensory and ANS fibers first, and then larger motor and proprioceptive axons.​

Question 20

T/F

The pt will Feel numbness first then loss of motor function

Answer 20

T

Question 21

onset of action of lidocaine and bupivacaine in a peripheral nerve block (PNB)

Answer 21

OOA: Dependent on LA pK​

Lidocaine: 3 minutes​

Bupivacaine: 15 minutes​

Question 22

duration of a LA in a PNB depends on the ____

Answer 22

dose

Question 23

the “stop light sign” can be seen in what block?

Answer 23

interscalene

Question 24

What is the Bier block?

Answer 24

IV injection of LA into an extremity isolated from the rest of the systemic circulation with a tourniquet​

Sensation and muscle tone dependent on tourniquet​

Question 25

What drugs are used for the Bier block?

Answer 25

Ester or amide LA can be used​ Mepivacaine > Lidocaine, but …​ Most commonly used: Lidocaine​

Question 26

in the Bier block what cuff do you deflate first?

Answer 26

distal, then proximal

Question 27

What is the sequence of neuraxial anesthesia

Answer 27

SNS​ Sensory​ Motor​

Question 28

Answer 28

(ANS first ) BP: will drop over 20mmHg HR: Increase (sensory 2nd) assess with cold alcohol pad to see if sensory is effected Motor is last. You then assess the movement of the extremity

Question 29

SAB is an injection of LA in _____

Answer 29

subarachnoid area of spinal cord

Question 30

With SAB youll have a ___ confirmation

Answer 30

CSF act on preganglionic fibers

Question 31

Sensory effect is on ___ level of denervation​ SNS effect is __ spinal segments cephalad of sensory​ Motor effect is___ spinal segments below sensory​

Answer 31

Sensory effect is on same level of denervation​ SNS effect is 2 spinal segments cephalad of sensory​ Motor effect is 2 spinal segments below sensory​

Question 32

T1-T4 is the ___ accelerator

Answer 32

cardiac

Question 33

If the assessed sensory level after SAB is at Thoracic 6 (Tip of Xiphoid Process), what are the: ​ SNS level​ Motor level of the block? ​ ​

Answer 33

T4 T8

Question 34

Most common drugs for SAB are:

Answer 34

Most common: Tetracaine, Lidocaine, Bupivacaine, Ropivacaine, and Levobupivacaine​

Question 35

SAB Dosage is according to what patient factor?

Answer 35

Height: Segmental level of anesthesia desired​ Duration of anesthesia desired​

Question 36

Pt is 5'5, how many mls will you give

Answer 36

1.5ml

Question 37

most common epidural anesthesia drug is ____

Answer 37

lidocaine

Question 38

onset of epidurals are......

Answer 38

15-30 min slow diffusion

Question 39

Epidural anesthesia can cross the placental barrier with the epidural and affect the fetus for ___ to ___ hr

Answer 39

24-48hr

Question 40

Bupivacaine or Lidocaine will cross the transplacental barrier more?​

Answer 40

lidocaine will because it is more rapid in onset (Dr, Castillo) ---> that answer seemed weird so ChatGPT said: Here's why: Lidocaine is less protein-bound (~65%) and has a lower lipid solubility, which allows more free drug to cross the placenta. Bupivacaine, on the other hand, is more protein-bound (~95%), which limits the amount of free drug available to cross into fetal circulation.

Question 41

There is ___ differential zone of SNS, sensory, and motor blockade between epidural and SAB

Answer 41

no Large doses required​ for the differential

Question 42

Tumescent Liposuction​ uses SQ infiltration of ____ volumes

Answer 42

large

Question 43

Tumescent Liposuction​ LA Plasma Peak is ___ to ____ hours s/p injection​

Answer 43

12-14

Question 44

Recommended dose:​ MAX Regional Anesthesia Lidocaine with Epi: ___ mg/kg​ MAX Highly diluted Lidocaine with Epi Tumescent: __ to __ mg/kg​

Answer 44

7 35 to 55 mg/kg​

Question 45

Theory: 1 gm of SQ can absorb up to __ mg of Lidocaine​

Answer 45

1

Question 46

Tumescent Liposuction requires Local anesthesia with ____ aspirates & prolonged postoperative analgesia​

Answer 46

bloodless