Regional 1 Flashcards
1.
define: neuraxial anesthesia
1.
anesthesia that causes a loss of sensation in a circumscribed region using regional anesthetics
2.
what dermatome does the C4 spinal level correspond with in regard to anatomy
clavicle
what level is T4-5
nipple region
what dermatome does C5 correspond with
what about C6
- C5=upper forearm and upper outer arm, 1/2 of second finger, 3rd & 4th fingers
- C6=lower forearm, thumb, first and 1/2 of second finger
what is Baricity
what is spec grav of hyperbaric, hypobaric, iso baric
the density of the CSF in compared to spinal anesthesia.
Isobaric=same density as CSF; spec grav 1.003-1.009
hyperbaric=heavier than CSF (will sink in spine) ;spec grav=1.015
hypobaric=lighter than CSF (will float up spine); spec grav=0.999
how is an isobaric block made
you can use CSF or sterile saline
- How would one do a hypobaric block?
2. what position should a person be in when receiving a hypobaric block (example a right hip surgery)
mix with sterile water (lighter than CSF)
the lying on the opposite of the affected side (unaffected side) or left side and the block will float up toward the affected (right) hip
8.
what does increasing the dose of the spinal affect the most?
It increases density somewhat?? but mostly increases the duration.
9. for bupivicaine (marcaine), if the dose is 1.8 cc of .75%, what is the dose in mg?
bupivicaine is 7.5 mg/cc,
if you are giving 1.8cc, divide 7.5 mg by 5 (7.5/5)=1.5mg for every 0.2 cc-add 1.5 mg for every 0.2 cc
or
7.5 x 1.8=13.5 mg
10.
- motor block is how many levels from your sensory block, and is it above or below?
- what about sympathetic level?
10.
- motor block is 2 levels below your sensory block
- sympathetic is 2 levels above your sensory block
11.
if you give a spinal and the patient is bradycardic and hypotensive, which would you treat first and which would you give:
atropine-0.5 mg or ephedra 10 mg?
Treat the bradycardia first since the hypotension is probably due to the low heart rate.
12.
- Patient has a headache post spinal or you get CSF while doing an epidural, what are the treatments?
- which is the best treatment?
- a)IV or PO caffeine (300 po or 500 iv)
b) theophylline 300 mg po
c) imitrex 6 mg sq
d) blood patch - Blood patch ( takes 2 persons), 20 ml blood is drawn and aseptically injected into the epidural space.
13.
if you are giving a spinal, you should palpate what landmarks and what level does that correlate to?
the crest of the ilium= body of L4 vertabra. you can go either in the space above and below this vertebra
14.
types of blocks
bracial plexus airway block femoral nerve block ankle block wrist block epidural spinal anesthesia (SAB)
15.
dermatome levels:
1. C3,C4,C5=?
diaphragm
16.
drematome C4=
clavicle
17.
dermatome C7=
cervical prominens
18.
dermatome T4-T5=
nipples
19.
dermatome T6-T8=
xiphoid
20
dermatome T10=
20.
umbilicus
21.
dermatome L4=
superior iliac crest
22.
dermatome s2-s5=
perineum
23.
dermatome T7=
inferior border of scapula
24.
dermatome L2
groin and outer thigh
25.
dermatome L3
mid outer thigh down to inner thigh, inner knee and upper calf; also across buttocks
26.
Dermoatome L4
inner soleus to outer knee
27.
Dermatome L5
outer gastroc to outer top of foot
28.
Name the different types of neurons in order of blockade (from most sensitive to LAs to least sensitive).
- B fibers (lightly myelinated)
- C fibers (non myelinated)
- A delta (myelinated)
- A gamma (myelinated)
- A beta (myelinated)
- A alpha (myelinated)
29. A alpha neurons 1. function 2. myelination type 3. diameter 4. degree of block (ease) function
- A-alpha
- large motor, proprioception
- heavy
- 12-20
- 1/4
(alpha male =big, knows your movements)
30. A beta neuron fibers 1. function 2. myelination 3. diameter 4. block degree (ease)
- A-beta
- touch, pressure, small motor
- heavy
- 5-12 um
- 2/4
(beta male=smaller, knows how you feel)
31. A gamma motor neurons 1. function 2. myelination 3. diameter 4. block degree
- A-gamma
- muscle spindles
- heavy
- 15-30 um
- 2/4
(gamma- body Guard is the muscle)
32. A delta 1. function 2. myelination 3. diameter 4. block degree
- A-delta:
- Acute PAIN, temperature
- heavy
- 2-5
- 3/4
(delta= the lookout, warns you)
33. B type 1. function 2. myelination 3. diameter 4. ease of block
- B
- preganglionic autonomic
- light
- <3 um
- 4/4
(B= controls your fight or flight)
34. C type 1. function 2. myelination 3. diameter 4. block ease
- C
- pain (chronic)
- none
- 0.4-1.2 um
- 4/4
(C= the nag)
35.
- what factors affect the differential blockade?
- what is the exception to the rule?
- -thickness of the nerve (thicker takes more blockade)
- myelination (increases succeptibility)
- location of the nerve in a spindle
- number of nodes of Ranvier (the more spread out, the harder to block) - B fibers are most succeptible to blockade although larger than C fibers
36.
what is the mantle effect?
nerve fibers on the outside of the bundle get blocked quicker, fibers toward the center of the bundle (motor) are harder to block
37. sympathetic: 1. function 2. myelination 3. diameter 4. blockade ease
- postganglionic
- no myelination
- 0.7-2.3
- 4/4
38.
what other factors affect blockade?
- tissue pH
- co2 tension
- local ion gradents
- frequency of nerve stimulation (how often sodium channels open)
39.
what are the amide LAs
- bupivacaine
- lidocaine
- etidocaine
- mepivacaine
- prilocaine
(B-L-E-M-P)
(remember 2 “i”’s= am”i”de)
40.
what are the Ester LAs
40. 1. tetracaine 2. cocaine 3. procaine 4. chloroprocaine (tetra-co-pro-chloro)
41.
where are amides metabolized?
liver (mostly)
42.
where are esters metabolized?
what is the allergan by product?
- in the blood by plasma cholinesterase
2. PABA
42.
How does degree of protein binding of a LA affect the chances of toxicity?
the more protein bound, the less the chance of toxicity
43.
what effect does lipid solubility have on potency of LAs?
the more lipid soluble, the more potent
44.
what efect on LAs does having a pKa closer to the body pH?
speeds onset (more un-ionized)