Exam 1 REVIEW Flashcards
Ion current: Resting phase
Na and K closed, K channels leaking
Ion Current Depolarization phase
Na channels open
Ion Current: Repolarization phase
Na channels closed, K channels open
Ion Current Refractory phase
Slow voltage gated Na channels closed and inactive
Methemoglobinemia associated with the use of
Prilocaine
Anatomical plane Sagittal plane
left and right
Anatomical plane: Coronal plane
Anterior and posterior
Anatomical plane: Transverse plane
Superior and inferior
Anatomical plane: Oblique
Cuts made diagonally
Which of the following locals has the lowest pka?
Mepivacaine = 7.6
Appropriate onset of the neuronal blockade
B autonomics 1 st A delta, fast pain/temp, C< slow pain, autonomics 2 nd A gamma, muscle tone, motor 3 rd A beta, sensory touch, pressure 4 th A alpha, motor skeletal muscle 5 th
Match the innervation of the anatomy to the block you would perform o cover that area
a. Suprascapular and axillary nerves to the shoulder joint –
Interscalene block
Match the innervation –> Rectus femoris from the femoral nerve, branches of the obturator nerve and quadratus femoris from the sacral plexus to the Hip joint
- SAB/ Epidural
Match the innervation –>Branches from the femoral nerve, the posterior division of the Obturator nerve and both division of the sciatic nerve to the Knee joint –
Femoral, Sciatic
Match the innervation –>The terminal branches of the Common Peroneal nerves, Tibial Nerve, and Femoral Nerve. Mainly, the entire Ankle Joint can be thought of simply as “innervation of the Sciatic and Femoral nerves”.
– Ankle Block
Match the innervation Terminal branches of the Brachial Plexus, including the Radial and Ulnar nerves. -
Wrist Block
I’m the following from the highest to the lowest with regards to LA rate of absorption:
TIC PBLSS
a. Tracheal 1 st
b. Intercosta 2 nd
c. Caudal 3 rd
d. Paracervical 4 th
e. Lumbar epidural 5 th
f. Brachial plexus 6 th
g. Subarachnoid 7 th
h. Subcutaneous 8 th
The major determinant of duration of action for a given local anesthetic used in a subarachnoid block (SAB) is:
a. The total dose of local anesthetic used
CNS toxicity manifest in several ways. Among the most prominent are 4 of the following:
a. Circa Memorial numbness
b. Tinnitus
c. Visual disturbances
e. Lightheadedness
Please choose the four correct statements regarding myelin sheaths from those listed below.
c. It is a continuous uninterrupted layer (EXCEPT)
a. It is formed by Schwann cells
b. It decreases capacitance across the axonal membrane
d. And helps spread impulse conduction
e. Not all Schwann cells form myelin sheaths
Lidocaine maybe used for all of the following: Choose 3
b. Increasing duration and peripheral nerve blocks (EXCEPT)
a. Infiltration of tissues
c. IV regional (bier) block
d. Epidural block
Peripheral nerves are constructed for electrical transmission that leads to a chemical messenger activation. Dendrites extend from the axon and are responsible for impulse transmission over long distances. Interruptions of the myelin sheath allow the axolemma to be exposed to the matrix. These interruptions are known as
c. Nodes of Ranvier
From the statements listed below, choose for answers you believe are TRUE:
e. Larger diameter nerves conduct much more slowly than smaller diameter nerves because they tend to be on
myelinated (EXCEPT)
a. A delta fibers – Sharp, prickling pain and temperature
b. C fibers - Throbbing pain and temperature
c. B fibers - Sympathetic and parasympathetic preganglionic neurons
d. Myelinated nerves conduct action potentials faster than unmyelinated nerves
How does carbonation affect local anesthetics?
a. Speeds the onset (relative to the use of HCl for pH adjustment)
Increasing the dosage of a local anesthetic administered for a nerve block will have 4 of the following effects:
b. Increase in onset time (EXCEPT)
a. More side effects and risk of complications
c. Prolongation of satisfactory anesthesia
d. More profound depth the block
e. More profound motor block
Match the terms with regard to local anesthetics:
a. Lipid solubility -
b. Protein binding –
c.
- potency
- duration of action
- shorter onset of action
- increases pH of solution, resulting in more drug in the unionize state
Which statement regarding pKa is FALSE?
Local anesthetics with higher pKa are more lipid soluble at physiologic pH
Amides or esters/
a. Which are more unstable in solution?
Esters
A vs E ? Which are metabolized by plasma cholinesterase?
Esters
A vs. E Which group is metabolized in the liver?
Amides
A vs. E Which group low allergic potential?
Amides
Nodes of Ranvier are: Choose 4
e. Located only unmyelinated nerves (EXCEPTION
a. Gaps between myelin forming Schwann cells
b. Where ion transfer occurs during depolarization
c. Where voltage gated sodium channels are concentrated
d. The site of local anesthetic action in myelinated nerves
Where in the CNS are the cell bodies of sensory neurons located?
a. Dorsal root ganglion
Which of the following correctly lists local anesthetic agents in order of longest duration to shortest duration when used for infiltration blocks? BuMeLiChlo
a. Bupivacaine, mepivacaine, lidocaine, chloroprocaine
description of each peripheral nerve layer.
a. Perineurium -
b. Endoneurium -
c. Epineurium -
contains nerve fibers in fascicles
surrounds each individual axon
sheath covering entire nerve
If you administer a basic local anesthetic with a pka of 8.2 into physiologic pH, the drug will be?
a. Greater than 50% ionized
Match the description with the correct type of nerve covering (answers can be used more than once)
a. Surrounds each individual axon________
b. Non-neuronal glial cell________
c. Contains nerve fibers in fascicles _____
d. Semipermeable, acts as a major barrier to diffusion of local anesthetics._________
e. Sheath covering the entire nerve ________
f. Contains nutrient blood vessels ________
Endoneurium Endoneurium (SN)
Perineum Perineum (Secon)
Epineurium (SHeconu)
Epineurium
Minimum Blocking Concentration is the lowest concentration of the drug that is needed for blocking impulse propagation. It is analogous to MAC. Match variables affecting the increase or decrease in the CM.
Increase (NMD)
Increased nerve fiber diameter
Increased myelination Increase
Greater distance between the Nodes of Ranvier
Decrease pHHighPreg El
d. Increased tissue pH
e. High frequency of nerve stimulator
f. Pregnancy
g. Elevated temperature
Originates from the ventral rami of C-1 C-5. Branches from this provide sensory innervation to part of the
scalp, neck, and upper shoulder. It also contributes motor innervation to some of the muscles of the nectar,
thoarcic cavity, and in the skin. –
Cervical Plexus
This plexus innervates the pectoral girdle and upper limb. This plexus is formed by five groups that originate
from the ventral rami of spinal nerves C-5 T1. –
Brachial Plexus
This plexus is formed by the ventral rami of spinal nerves L1-L3 and the superior branch of L4. In some
cases there is a contribution from T12. Branches of this plexus are the ileohypogastric, ilioinguinal,
genitofemoral, lateral femoral cutaneous obturator and femoral nerves. –
Lumbar Plexus
This arises from the lumbosacral trunk L5-L4 plus the ventral rami of S1-S4. The main nerves include the
sciatic, and the pudendal –
Sacral Plexus
These fiberss are subdivided in Alpha, Beta, Gamma, and Delta. They are all myelinated, responsible for
motor, tactile, proprioception, muscle tone, touch –.
A fibers
These fibers are usually my unmyelinated, slow, postganglionic autonomic, responsible for pain and
temperature –
C fibers
These fibers are myelinated, preganglionic autonomic –
B fibers
And a healthy adult the maximum dose of lidocaine without epinephrine is a
175 mg (Dose should not be repeated at intervals of <3hrs and max dose of 400 mg in 24 hrs. should never be exceeded)
In what state are local anesthetics stored?
Base in acid solution – ionized pH
Which of the following preservative free local anesthetic solutions would be a good choice for patient with severe
allergy to PABA containing sunscreens?
c. Bupivacaine
