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)
45.
what affects absorption rate of LAs?
dose and pharmacological properties
46.
what affects onset and duration of LA?
volume and concentration
47.
what does the use of vasoconstrictors do in regards to LAs?
limits systemic absorption and maintains drug concentration in the vacinity of desired action.
48.
why does epi not have as much of an effect on bupivicaine than on lidocaine?
bupivicaine has a greater lipid solubility and is therefore more potent.
49.
- what is the onset of a SAB?
- onset of an epidural?
- SAB onset=2-5min??
2. epidural onset10-15 minutes
50.
what does blood flow at the site of local injection do to duration?
50.
shortens duration as the drug is distributed to the rest of the body (where you dont need it).
51.
what is the order of regions with highest blood flow (and therefore higher peak plasma concentrations and shorter duration)
- intercostal space
- caudal
- epidural
- brachial plexus
- sciatic/femoral nerves
(I-C-E–B-S)
52.
what does the addition of bicarb do to the LA?
speeds onset by increasing the pH of the LA, which creates more un-ionized molecules (unionized go thru the membrane and are the active molecules in blockade).
53.
what does an increase in pKa of LA cause
increased ionized form (lipophobic)=decreased diffusion and slower onset
54.
increased pH causes what?
increased non ionized form (lipophilic)=increased ease of diffusion and faster onset
55.
1,2,3. name 3 potential side effects of LAs
4. how often do these happen?
- PABA allergy from Esters (para-aminobenzoic acid is a metabolite of methylparaben (which is a preservative in esters)
- reaction from excess plasma accumulation of LA
- reaction to epinephrine
- rare
56.
cross sensitivities:
1. if allergic to one ester will you be allergic to all esters?
2. will you be allergic to amides?
- yes. they all share para-aminobenzoic acid metablolite
2. no, if allergic to ester, you CAN use an amide THAT IS PRESERVATIVE FREE (no cross sensitivity).
57.
local tissue toxicity and tissue injury:
1. how often?
2. what are examples?
- rare
- neurotrauma
- direct damage from needle
- irritation from large concentrations of LA
- contamination of LA
- contamination of needle with skin perp (alcohol, chloahex and betadine are neuro toxic) which irritates the nerve
- nerve compression
- systemic hypotension=hypoperfusion of nerve tissue
58.
neurotrauma:
1. what is cauda equina syndrome?
2. what is a potential cause?
- injury across lumbosacral plexus causing sensory dysfunction, loss of bowel and bladder function and paraplegia.
- 5% lidocaine thru a small bore needle (causes more pressure and a direct trajectory of lidocaine into the nerve), lidocaine is not used in spinals anymore.
59.
neurotrauma:
1. what is transcient neurologic syndrone (TNS)?
2. onset and duration
- transcient pain or dysthesia in the legs or buttocks after SAB
- 6-36 hrs, resloves in 7-10 days
60.
what is reflex sympathetic dystrophy?
aka: complex regional pain syndrome (CRPS) or Causalgia:
a chronic condition in which severe pain is continuous to a post surgical area which may also cause inflammation of the skin. (may be from sensitization of the neurons in that area(allodynia)). the condition can spread from trauma.
61.
what causes systemic toxicity?
what are side effects?
61. 1.accidental intravascular injection 2. - numb lips/tongue -metalic taste - tinnitus -slurred speech, light headed, visual changes -muscle twitch -vertigo -seizure -coma -resp arrest -cv collapse
62.
insertion of needle in order
- skin
- sq
- supraspinous ligament
- interspinous ligament
- ligamentum flavum
(you should never hit posterior ligament (anter ligament is infront of the body of the spine).
63.
where does the conus medularis end in infants?
- L3
2. never perform SAB in infants above L4
64.
- pairs of spinal nerves?
- where is CN 8?
- 31 (8, 12, 5, 5, 1)
2. C8 is bwtween C7 & T1
65.
- amount of csf in 1 day adult?
- how much CSF available in CNS in adult?
- in child/
- 500 ml/day
- 150 ml at a time; (0.3 ml/day which turns over 3x/day)
- 50 ml
66.
- what is the filum terminale an extension of?
- what is this ?
- what else does it form (“lions teeth”)
- pia mater
- membrane closest to the brain and cord,
- denticulate ligaments
67.
where is the epidural space widest and most narrow?
- widest at L2 (5-6 mm)
2. narrowist at C5 (1-1.5 mm)
68.
where is sympathetic ganglionic chain?
T3-L3
69.
what is difference between subdural “space” and subarachnoid space?
sub dural is a potential space but subacachnoid is actual space
70.
- from which vessels do the posterior spinal arteries originate?
- what part of spine do they supply
- how many are there
- how do they travel and what do they anastamose with?
70.
- originate from posterior inferior cerebellar arteries which become the vertebral arteries
- posterior cord and the anterior 1/3 of cord
- (2) left and right
- travel in the sub arachnoid space and anastamose with the anterior spinal artery via segmental medullary arteries
71.
- anterior spinal arteries arise from ___?
- and supply ___?
- vertebral arteries
2. anterior 2/3 of cord
72. which vessel (anterior or posterior) supplies most of the cord?
anterior
73.
- what do radicular arteries supply?
- what are the names?
- what can happen during aortic grafting
- supply every spinal nerve root, and enter every intervetral foramen (but are not connected to anterior and 2 posterior longitudinal arteries) they ARISE FROM AORTA.
- cervical radicularis
- –thoracic radiculars
- –radicularis magna at lumbar area (L1-L2). - the radicularis magna can lose blood supply when the aorta is cross clamped which causes ischemia leading to paraplegia
74. from where does.. 1.cervical radicular artery arise? 2. thoracic radicular? 3. radicularis magna?
- subclavian
- descending aorta
- descending aorta
75.
what is the difference between sacral hiatus in adults and children?
usually closed in adults
76.
what procedures could get a SAB?
lower abd, lower ext, gyn, obstetric, perineal and rectal, urological
77.
absolute contraindications to spinal
patient refusal sepsis at site hypovolemia coagulopathy indeterminate neuroo disease increased ICP
78.
relative contraindications
infection distinct from site of injection
unknown duration of surgery
inability to communicate with patient
prior back surgery
79.
what vertebra level is a low spinal at
T10 (umbillicus)
80.
sacral block have what distribution
80.
“saddle” perineum, perianal, genetalia (s1-s3)
81. recommended block (range) height for perirectal, perianal etc?
S4- L1
82.
rec. block height for lower ext surgery
T10-T8
83.
rec. height for hip and genetalia, fem pop
T10
84.
rec. height of block for lower abdomen surgery (TAH, inguinal herniprrhaphy, appe)
T4
85.
rec. height of upper abdomen block for open chole, abdomen exploration
T1
86.
- what is a total spinal (what level)
- what is affected?
- C8
- -sensory to little fingers
- motor up to thoracic muscles (cause SOB)
- autonomic (cardiac accelerators ((T1-4) are blocked=hypotension)
87.
high spinal is what vertebra (dermatome)
- T4 (nipple line)
- motor-sacral, lumbar, abdomen muscles
- autonomic effects-total sympathectomy (decreased BP, CO-d/t decreased preload). (lower abdomenal surgery)
88.
low spinal is at which level
- T10 (to T8)
2. affects autonomic (sympathetic) causing vasodilation with only slight decrease in BP (NO change in CO or HR).
89.
how much epi do you add to your spinal LA?
0.2 mg of 1:100,000
90. lidocaine : 1. what is% 2. what baricity types given 3. dose for L4 4. dose for T10 5. dose for T4 6. duration 7. duration with epi
- lido:
- 5%
- hyperbaric-only
- L4=40-50mg
- T10=50-75 mg
- T4=75 mg
- duration: 60-90 min
- duration w/ epi: 60-90 min
91.
what s/e can accompany epi use with LAs
urinary retention
92. bupivicaine: 1. % 2 types of baricity given 3. dose for L4 4. dose for T10 5. dose for T4 6. duration 7. duration with epi
bupiv.
- 75%
- hyper or iso
- L4=7.5
- T10=10-12 (10 isobaric)
- T4=15
- duration: 90-150 (same for isobaric)
- duration w/ epi: 90-150 min (same for isobaric)
93. tetracaine 1. % 2. baricity types 3. dose for L4 (hypobaric,)?(hyperbaric)? 4. Dose for L10 5.dose for T4 6. Hypo/hyper w/ epi 7. Hypo/hyper without epi
tetra:
- 1%
- hyperbaric & hypobaric
- T4=5mg (hyperbaric) 5-10mg (hypobaric)
- T10=6-10mg
- T4=12-15mg
- with epi:180-270 hyperbaric/ hypobaric
- without epi:120-180 hyperbaric/hypobaric
94.
where does supraspinous ligament extend to
c7 to sacrum
95.
teratment for toxicity
- benzos, barbs, prop to raise seizure threshold
- cv support
- resp support
96.
who is more sensitive to bupivicaine toxicity
pregnant
97.
lidocaine max dose/kg
1. without epi
2. with epi
- 4 mg/kg
2. 7 mg/kg
98. mepivicaine max doses/kg 1. Without epi? 2. --with epi?? 3. mepivicaine max
- 7 mg/kg
- –no epi with mepivicaine
- (400 max)
99.
bupivicaine max dose/kg
1. without epi
2. with epi
Marcaine (bupiv)
- 2 mg/kg
- 3 mg/kg
100.
etidocaine max dose/kg
1. Without epi
2. With epi
100.
- 6 mg
- 8 mg with epi
101.
procaine max dose/kg
101.
7 mg/kg
102.
tetracaine max
???
103.
chloroprocaine
1. Withput epi?
2. W/ epi?
103.
11mg/kg
14 mg/kg with epi
104.
cocaine max dose/kg
104.
1.5 mg/kg
105. narcotics 1. fantanyl (spinal, epidural)--onset--duration 2. morphine(spinal, epidural) 3. deomorol (spinal, epidural) 4 sufantanil (spinal, epidural)
105.
fent-50:100 mcg/10-25 mcg–5 min–2-3 hrs
morphine:2-5mg/ 0.1-0.3 mg–45 mn–12-24 hrs
demorol: 25-50 mg/ 10 mg–15 min–4-6 hrs
sufenta: 30-50 mcg/ 2.5-5 mcg–5 min–2-3 hrs
106.
intrathecal morphine has highest incidence of?
106.
resp depression
107 Lidocaine 2% 1.4ml =? mg 1.6 ml=? mg 2.0ml=? mg
107.
- -1.4 ml / 0.2mg = 7mg therefore: 1.4ml =7 mg
- -1.6 ml=8 mg
- -2.0ml=10 mg
108.
bupivicaine .75%
1—1.2cc=
2.—5 cc=
- .75%=7.5 mg/cc
- (1.2 x 7.5=9) therefore 1.2cc=9mg
- 37.5 mg
109.
what is at the “——” line between iliac crests on spine?
109.
“Tuffier’s or intercristal” line (aka Jacoby’s line)
–body of L4 vertebra
110.
what is the 2 above/ 2 below rule (above and below what?)
110.
pertains to block involvement with sympathetic, sensory, motor in the spine. sensory is the desired effect, but it maps out how the others are involved. sensory block of L2=sympathetic block of T12 and a motor block of L4.
(sympathetic is 2 above sensory, motor is 2 below sensory)
111.
to make LA hyperbaric, what is it mixed with?
111.
dextrose
- what increases the chances of pdph?
2. what size should you use?
- larger needle
2. 25-27 guage (22g for old arthritic persons)
how much additive to SAB:
- fentanyl?
- epinephrine?
- morphine?
- fentanyl: 20 mcg (.2 cc)
- epineprine: 0.2 mg
- morphine: 100-200 mcg (0.1-0.2 mg of 1 mg/ml)