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APA 1 > Regional Anesthesia > Flashcards

Regional Anesthesia Flashcards

1
Q

How do you tell the difference between esters and amindes?

A 
ESTERS
Procaine
cocaine
tetracaine
chloroprocaine	
AMIDES
lidocaine		
mepIvacaine
bupIvicaine
etIdocaine	
ropIvacaine
(have I’s in the beginning)
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2
Q

The amine portion makes LAs

A

hydrophilic

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3
Q

What is the ester chain

A

C-O-C

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4
Q

What is the amide chain

A

N-H

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5
Q

What is pKa

A

The pH at which 50% of the local anesthetic is ionized and 50% unionized

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6
Q

All LA have a pKa between

A

7.6-9.1

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7
Q

Is it the charged or uncharged molecule that is the most lipophilic and can access to the axon

A

unionized

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8
Q

pKa is only the _____ of onset. The ______ the pKa the faster the onset

A

speed

lower

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9
Q

LA needs to _______ to get into the cell. Inside the cell is _______ and the LA becomes _______. When ionized, it gets stuck in the cell and can attach to the receptor

A

unionized
acidic
ionized

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10
Q

MOA: Block nerve conduction by impairing propagation of the action potential in

A

axons

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11
Q

MOA: Decrease the rate of rise of the action potential such that the threshold potential is

A

not reached

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12
Q

MOA:

Interact directly with specific receptors on the Na+ channel, inhibiting

A

Na+ ion influx

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13
Q

How does lipid solubility effect the duration of action

A

increases potency

does account for some duration of action

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14
Q

How does protein binding effect the duration of action

A

a high degree of protein binding will prolong the duration of action

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15
Q

How does pKa effect the duration of action

A

speed of onset

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16
Q

Thick or thin fibers are more easily blocked

A

thin

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17
Q

Mylinated or unmylinated fibers are more easily blocked?

A

mylitated

produce block only at Node of Ranvier

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18
Q

Describe A alpha fibers

A

12-20mm

motor & proprioception

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19
Q

Describe A beta fibers

A

5-12mm

Touch (pressure) & proprioception

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20
Q

Describe A gamma fibers

A

3-6

Motor (muscle spindles)

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21
Q

Describe A delta fibers

A

2-5

Pain, touch, temp (cold)

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22
Q

Describe B fibers

A

<3mm

Preganglionic autonomic fibers

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23
Q

Describe C fibers

A

0.4mm

Pain (sharp), touch, temp (hot &cold)

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24
Q

Which fibers are NOT mylinated?

A

C fibers

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25
Q

Which fibers will be blocked first?

What will you see with this?

A 
B fibers (with a little bit of C)
periph vasodilation and elevated skin temp
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26
Q

What is the sequence of block

A

ATP/TP/MVP

Automatic touch pain
Temp pressure
Motor vibration proprioception

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27
Q

How are esters metabolized? How long is their half life in circulation?

A

plasma cholinesterase

about 1 minute (short!)

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28
Q

Degradation product of ester metabolism is a metabolite related to

A

p-aminobenzoic acid. (PABA)

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29
Q

How are amides metabolized? Where does this happen? How long is the elimination half life?

A

amide linkage is cleaved through N-dealkylation followed by hydrolysis.

This occurs primarily in the liver.

Elimination half-life is 2-3 hours.

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30
Q

What patients may be more susceptible to adverse reactions from amide local anesthetics.

A

severe hepatic disease

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31
Q

Does amount of local anesthetic in the liver matter to the length of the block?

A

No, because the site of action is the nerve

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32
Q

Local anesthetic solutions are classified as hypobaric, isobaric or hyperbaric based on their _____ relative to the density/specific gravity of cerebral spinal fluid (CSF).

A

density

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33
Q

What is the specific gravity of CSF?

A

1.003–1.009 at 37*C.

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34
Q

A hypobaric LA will

A

float

if you leave them sitting up = high spinal

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35
Q

An isobaric LA will

A

sit right where you put it (same baricity as CSF)

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36
Q

A hyperbaric LA will

A

sink

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37
Q

What happens if you don’t lay a patient down right away that got a hyperbaric LA block?

A

saddle block

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38
Q

Baricity changes level for about

A

5 minutes

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39
Q

What does adding epi to a LA do?

5 things

A
  • Prolong duration of anesthesia
  • Decrease systemic toxicity by decreasing rate of absorption
  • Increase intensity
  • Decrease surgical bleeding
  • Assist in eval of test dose (HTN/tachy if accidental inject into vein/artery)
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40
Q

When would you NOT add epi to your LA?

4 reasons

A
  • block in area with poor collateral circulation (NO fingers, toes, penile block with epi)
  • Bier Block (IV regional)
  • IV LA (when take tourniquet down - big flush of epi)
  • History of severe uncontrolled HTN, CAD, arrhythmia, hyperthyroid, utero-placental insufficiency.
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41
Q

What could you add other than epi that would be better for HR

A

Phenylephrine

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42
Q

What does adding sodium bicarb to a local anesthetic do?

A

Raised the pH and increases the concentration of unionized (free) base

Increases rate of diffusion

SPEEDS UP ONSET

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43
Q

1mEq added to each 10ml of _____ or _______

A

lidocaine or mepivacaine

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44
Q

0.1mEq added to each 10ml of ________

A

bupivicaine

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45
Q

What does adding an opioid (50-100ug fentanyl) to a LA do? (3 things)

A
  • Shortens the onset (makes it work quicker)
  • Increases the level
  • Prolongs the duration of a regional block.
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46
Q

When an opioid is added to a LA, a selective action at the _____ _____ of the spinal cord modulates pain transmission.

A

dorsal horn

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47
Q

Adding an opioid to a LA, action is _______ with the action of the local anesthetic.

A

synergistic

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48
Q

Why would you add precedex or clonidine to a LA?

A

to prolong the block (up to 72hrs)

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49
Q

T/F: true allergic reactions are rare

A

True

Must be differentiated from non-allergic responses such as syncope and vaso-vagal reaction.

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50
Q

Describe allergic reactions to Amides

A

essentially devoid of allergic potential.

If a methyl-paraben preservative is used, it may produce allergic reaction in someone allergic to PABA.

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51
Q

Describe allergic reactions to Esters

A

may cause allergic reaction due to metabolite similar in structure to PABA.

Also may produce allergic reaction in persons sensitive to sulfonamides or thiazide diuretics.

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52
Q

Is there cross sensitivity between esters and amides?

A

NO, if allergic to one class, give the other

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53
Q

How does systemic toxicity occur?

A

accidental intravascular injection or overdose of local anesthetic

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54
Q

What are ways to minimize systemic toxicity?(4 things)

A

Aspiration prior to injection (if you get block back DO NOT inject)

Use of epi-containing solutions for test dose
Will see tachycardia

Use of small incremental volumes to establish the block
5 check, 5 check

Use of proper technique during IV regional
Bier block

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55
Q

What are symptoms of CNS toxicity?

A

Lightheadedness
Tinnitus
Metallic taste

Visual disturbance

Numbness of tongue and lip

May progress to:
Muscle twitching
Loss of consciousness
Grand mal seizure
Coma
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56
Q

What should you do it a patient starts to complain of any S/S of CNS toxicity?

A

STOP injecting

In a periperal nerve block, they should not get lightheadedness tinnitis, etc

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57
Q

When someone arrests from systemic toxicity, why won’t normal drugs work?

A

Because we are blocking all the Na channels with our LA. We need to give lipids and do compressions until level of block comes down.

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58
Q

What LA has the highest seizure threshold?

What LA has the lowest seizure threshold?

A

Procaine

Bupivicaine (more likely to see seizures)

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59
Q

What do you need to do if a patient start to have seizures with a LA?

A

blow off CO2
Midazolam 1-2 mg
Thiopental 50-200mg
Propofol

Amin 100% O2

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60
Q

What is the clinical presentation to cardiovascular toxicity from a LA?

A

Decreased contractility
Decreased conduction
Loss of vasomotor tone
CV collapse

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61
Q

What are the 2 most CV toxic LAs?

A

bupivacaine (MOST) & etidocaine

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62
Q

Treatment of CV toxicity

A

Administer O2

Support the circulation with volume, vasopressors, and inotropes

ACLS if indicated

Treat V-tach with cardioversion

Prolonged cardiopulmonary resuscitation may be required until the cardiotoxic effects subside with drug redistribution. (up to 45 minutes)

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63
Q

For CV toxicity, what is the dose of lipid emulsion?

A

1.5 ml/kg over 1 min
Drip 0.25 ml/kg/min

repeat bolus q3-5 min for a Max 3 ml/kg

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64
Q

What 2 monitoring devices MUST be on before putting a block in?

A

pulse ox and BP cuff

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65
Q

T/F: Research suggests that post-op morbidity and possibly mortality may be reduced when neuraxial blockade is used, either alone or in combination with general anesthesia.

A

True

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66
Q

Name some benefits of using an Neuraxial blockade

A 
REDUCED INCEDENCE OF
venous thrombosis
pulmonary embolism
cardiac complications 
vascular graft occlusion
respiratory depression and pneumonia
blood loss and transfusion      
allows earlier return of GI function
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67
Q

How is a Neuraxial Blockade accomplished?

A

by injecting local anesthetic solution into the cerebral spinal fluid within the subarachnoid/intrathecal space.

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68
Q

Why do you use less LA when performing a neuraxial blockade in the subarachnoid space?

A

because injecting it right where nerves are

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69
Q

Indications for a spinal

A

Surgery of lower abdomen

Surgery of lower extremities

Surgery on perineum

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70
Q

Skin infection at the site of injection increases the risk of meningitis or epidural abscess. Aseptic technique MUST be adhered to. Other factors that increase the risk of infection include skin conditions such as

A

psoriasis, underlying sepsis, diabetes, immunologic compromise, steroid therapy, history of HIV or herpes simplex virus

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71
Q

What is the most common causative organism in the epidural abscess?

A

phylococcus aureas (MRSA)

72
Q

How is an epidural abscess diagnosed and treated?

A

diagnosed by MRI, early aggressive surgical intervention and antibiotics.

73
Q

According to Levi, what is the ONLY ABSULUTE CONTRAINDICATION to a spinal

A

Pt refusal

74
Q

guidelines for anticoagualted patients:

ASA/NSAIDS

A

no contraindication

75
Q

guidelines for anticoagualted patients:

Heparin

A

place catheter 1 hour prior to administering heparin

Catheters should be pulled when heparin activity is at a minimal level. Ie. An hour before the next dose

76
Q

guidelines for anticoagualted patients:

Clopidogrel & abciximab

A

discontinue 7 days preop

77
Q

guidelines for anticoagualted patients:

Xarelto

A

discontinue 3 days preop

78
Q

What are the herbal subelements that can effect blood clotting?

A

“G” Herbals
Gingo, Ginsing

Fish oil

79
Q

What S/S would have you concerned for a Spinal or epidural hematoma

A

New onset weakness to lower limbs and sensory deficit
New onset back pain
New onset bowel or bladder dysfunction
OR
Spinal never wears off (very nervous at 5 hrs)

80
Q

What must happen for the best outcome of a spinal hematoma

A

Must diagnose and surgically decompress hematoma within 8 hours for best outcome

Or become paraplegic

Will need emergent MRI

81
Q

Risk of permanent neurologic damage

Spinal anesthesia

Epidural anesthesia

A

Spinal anesthesia 1-4.2 : 10,000

Epidural anesthesia 0-7.6 : 10,000

82
Q 
Dermatomes
C6
C8
T4
T7
T10

T1-T4
C3,4,5

A 
C6 - thumbs
C8 - pinky
T4 - nipple line
T7 - xiphoid
T10 - belly button

T1-T4 - cardiac accelerators (above bradycardia, treat with atropine/epi)

C3,4,5 - diaphragm

83
Q

Level required for surgery

Lower extremities
Hip
Vagina/uterus
Bladder/prostate
Lower extremities/TQ
Testis/ovaries
Lower intraabdominal
Other intraabdominal
A 
Lower extremities          T12
Hip                                   T10
Vagina/uterus                  T10
Bladder/prostate             T10
Lower extremities/TQ     T8
Testis/ovaries                   T8
Lower intraabdominal     T6
Other intraabdominal      T4
84
Q

How many vertebra

cervical vertebra
thoracic
lumbar
sacral
coccygeal
A 
7 cervical vertebra
12 thoracic
 5 lumbar
 5 sacral
 4 coccygeal
85
Q

Why is the lumbar a good place to insert a needle to enter spinal canal?

A

spinal processes are straight

86
Q

Thoracic spinal processes are angled, what does this mean

A

you need to enter the spinal canal at a deep angle

87
Q

The sacral region is all fused, what type of block is this

A

caudal block

88
Q

connects apices of spinous processes.

A

Supraspinous ligament

89
Q

connects the spinous processes.

A

Interspinous ligament

90
Q

connects the caudal edge of the vertebra above to the cephalad edge of the lamina below

A

Ligamentum flavum

91
Q

When doing a midline approach, what is the order that the needle will pass though

A

Skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum

92
Q

The spinal canal extents the length of the spinal cod during fetal life, but end at _____ at birth

A

L3

93
Q

Spinal cord moves progressively cephalad eventually reaching the adult position of ____ by 2 years of age.

A

L1 (conus medularis is here)

94
Q

The conus medularis, lumbar, sacral, and coccygeal nerve roots branch out distally to form the

A

Cauda Equina

95
Q

Spinal needles are placed below ___ as the mobility of spinal nerves reduces the danger of needle trauma.

A

L2

96
Q

Where is the Pia mater located?

A

against the spinal cord

97
Q

What is the dura mater?

A

tough fibrous sheath running the length of the cord.

98
Q

What is the arachnoid?

A

lies between the dura and the pia mater.

99
Q

What is total volume of CSF (brain and ventricles)

Volume of CSF in the spinal canal

A

~140 ml

30-80 ml.

100
Q

CSF is continuously formed at a rate of

A

500 ml/day

20.8 ml/hr

101
Q

CSF is formed predominantly by the _____ _______ of the cerebral ventricles.

A

choroid plexuses

102
Q

Normal CSF pressure?

A

10-20 cm H2O pressure.

103
Q

Factors affecting spinal (subarachnoid block):

Drug Dose - the level of anesthetic varies directly with the _____ of local anesthetic used.

A

dose

104
Q

Factors affecting spinal (subarachnoid block):

Drug Volume: – the greater the volume of injected drug, the _____ the spread within the CSF.

A

Farther

105
Q

Factors affecting spinal (subarachnoid block):

Turbulence of CSF – turbulence ______ the spread of the drug and the level of blockade obtained.

A

increases

106
Q

What are some ways to create turbulence?

A 
Rapid injection 	
Barbotage (aspirate, push....)
Coughing
Excessive pt. movement
Increased intra-abd pressure
Spinal curvature
Baricity
107
Q

Hyperbaric solutions are the most common local anesthetic solution for spinal anesthesia. How is this achieved?

A

by adding glucose (dextrose) 5-8% to the drug.

> 1.0015

108
Q

How do Hyperbaric solutions settle down?

A

Due to gravity

109
Q

Hypobaric solutions will flow to the highest part of the CSF volume. How is a hybobaric solution achieved?

A

By adding sterile water

<0.999

110
Q

What would a hypobaric solution be for?

A

Perineal procedures in prone – jackknife.

111
Q

What is the theoretical advantage of isobaric solution?

A

predictable spread through CSF independent of patient position.

It will remain where injected

112
Q

True/False: Increasing the dose of an isobaric anesthetic will affect duration of anesthetic more than spread to higher dermatome.

A

True

113
Q

Describe the Quincke needle and what its advantage is

A

has a cutting bevel tip

hold the bevel direction parallel to the longitudinal dural tissue fibers to minimize the rick of PDPH.

114
Q

Describe the whitacre sprotte needle

A

pencil point tip, holes on side

115
Q

Describe the rtie marx needle

A

Pencil point tip, more round holes on side

116
Q

Describe the touhy needle

A

Epidural needle 17-18 guage, rounded at the top

117
Q

What are the sizes of the spinal needles?

What size do we normally use?

A

22-29 gauge and in lengths of 3.5 - 5 inches

25-27 gauge 3.5 inch needle

118
Q

Recent dada suggest using a _________________ - less PDPH, drag less contaminants into subdermal tissue, pierce the dura with a clearly perceptible “click” or POP not appreciated as easily with cutting tip

A

noncutting tip needles (pencil point )

119
Q

Positioning: Lateral - how is patient laying?

A

Knees drawn up to chest and chin flexed downward to chest to obtain maximal flexion of spine.

120
Q

When patient is laying in the lateral position for a spinal, what way will they be laying for a hypobaric solution? for a hyperbaric solution?

A

Affected side up if using hypobaric technique

affected side down if hyperbaric technique.

121
Q

What is the line called between the top of the iliac crests, where is this anatomically?

A

tuffiers line, aligns with L4

122
Q

Positioning: sitting - how is the patient positioned?

A

Head and shoulders are flexed downward onto the trunk with patients back close to the edge of the table

123
Q

Who is the sitting position for spinal anesthetics good for?

A

obese patients

124
Q

Sitting position is used in conjunction with hat type of spinal anesthetic?

A

hyperbaric

125
Q

What position are patients place in while awake when prone? What anesthetic is this good for?

A

prone jackknife while awake

Used with hypobaric solutions
surgeries on rectum, perineum, anus

126
Q

When advancing the needle through the midline approach, how if the needle positioned?

A

Needle is advanced through the skin in the same plane as the spinous processes with a slight cephalad angulation toward the intralaminar space.

127
Q

When do you use the paramedian approach?

A

Useful in patients who cannot be maximally flexed or whose intraspinous ligaments are ossified.

128
Q

When advancing the needle through the paramedian approach, how if the needle positioned?

A

Spinal needle is placed 1-1.5 cm lateral to midline of selected interspace.

Needle is aimed medially and slightly cephalad and passed lateral to the supraspinous ligament.

129
Q

What spaces can spinal anesthesia be administered?

A

L2-L3, L3-L4, or L4-L5.

DONT go above L2

130
Q

When preparing for a spinal, clean a large area with

A

antiseptic solution.

131
Q

Avoid contamination of spinal kit with antiseptic solution – this is

A

potentially neurotoxic.

132
Q

Infiltrate skin at intended spinal puncture site with

A

1% lidocaine solution. (25 gauge needle)

133
Q

Insert the needle so that its bevel is ______ to the fibers that run longitudinal to reduce the incidence of post – dural puncture headache.

A

Parallel

134
Q

Advance needle until increased resistance is felt as it passes the _____ _____. A sudden _____ or loss of resistance is felt as the needle is advanced beyond this ligament.

A

ligamentum flavum.

“Pop”

135
Q

Remove the stylet from the needle. Correct placement is confirmed by ___________ into the hub of the needle.

A

Free flow of CSF

136
Q

____________ occurring with placement of the needle requires immediate withdrawal of the needle and repositioning.

A

Paresthesia (shooting pain)

137
Q

The hub of the needle may be rotated in __________ until good flow is established.

A

90-degree increments

138
Q

After you connect the syringe with the LA to the needle, _______ confirms free flow of CSF. Drug is _______ injected. __________ of CSF at end of injection confirms the needle tip is still in the __________ space. The needle is gently removed and the patient is placed in the desired position.

A

aspiration
slowly
Re-aspiration
subarachnoid

139
Q

The ascending anesthetic level is assessed using ______ or _______

A

pinprick or alcohol swab.

140
Q

Blood pressure, heart rate and respirations are closely monitored how often until patient is deemed stable.

A

(at least once a minute)

141
Q

Fixation of local anesthetic takes approximately

A

20 minutes.

142
Q

Differential neural blockade:

_____ fibers conveying _______ impulses are more easily blocked than larger sensory and motor fibers.

A

Smaller C

autonomic

143
Q

The level of autonomic blockade therefore extends two or three segments _____ the sensory blockade.

A

above

144
Q

Fibers conveying ______ are more easily blocked than larger motor fibers.

Sensory blockade therefore extends two or three segments above motor blockade.

A

sensation

145
Q

Neural Blockade

______ >_______>______

A

Autonomic > sensory> motor

146
Q

Hypotension is proportion to the degree of _______ block achieved. Sympathetic block dilates both arteries and veins ______ the level of the block

A

proportional

below

147
Q

Why will hypotension be more profound in the younger patient than older patients

A

elderly arteries are more atherosclerotic and won’t dilate as much

148
Q

T/F: HR changes significantly with spinal

A

False
Heart rate does not change significantly in most patients. (baroreceptor in neck still okay)

Significant bradycardia does occur in 10-15% of patients.

149
Q

When does the risk of bradycardia increase?

A

Risk of bradycardia increases with increasing sensory levels of anesthesia.

Block of cardio-accelerator fibers T1-T4.

150
Q

To help prevent a CV response to a spinal, what should you do?

A

Fluid load with 500-1000cc IV prior to spinal blockade if history allows. (15 ml/kg)

151
Q

Treatment for a CV response

A 
Oxygen mask
Vasopressors
Atropine (0.4-0.8)
Epinephrine
CPR
152
Q

What is the agent of choice for symptomatic brady and hypotension with a spinal

A

ephedrine is a mixed alpha and beta agonist

153
Q

Cardiovascular effects ______________
and steps taken to minimize the degree of
hypotension and bradycardia.

A

should be anticipated

154
Q

Are pulmonary changes with spinals common?

A

usually minimal.
C3,4,5 are still okay
This will take away the sensation of breathing

155
Q

What patients respiratory status may be affected with a spinal

A

Pts. with chronic lung disease who rely upon accessory muscles of respiration to actively inspire or exhale may be affected. These muscles will be impaired below the level of the block.

won’t be able to cough

156
Q

The clinically important factors that can be controlled by the anesthetist are:

A
  • Total dose of anesthetic
  • Site of injection
  • Baricity of the drug (drug choice)
  • Position or posture of the patient after injection
157
Q

What are some complications of spinal anesthetic? (7)

A 
Failure of block
Postdural puncture headache
High spinal
Nausea
Urinary retention
Hypoventilation
Backache
158
Q

When you give an epidural, you stop just prior to the _____.

A

dura

this is a potential space

159
Q

Epidural space
In the lumbar region the epidural space is
_____ wide at midline.

In the mid-thoracic region the epidural space is _____ wide.

A

5-6mm

3-5mm

160
Q

Local anesthetic placed in the epidural space acts directly on the _________ _________ _________ located in the lateral space.

A

spinal nerve roots

161
Q

True/False: Onset of block for epidural is slower and intensity is less.

A

True

Need to give more drug than with spinal (has to soak through all layers)

162
Q

Anesthesia develops in a segmental manner and ______ blockade can be achieved.

A

selective (between 2 areas)

spinals block from level of injection down to toes

163
Q

Epidural anesthesia can be titrated to deliver _____ or ______

A

analgesia or anesthesia

164
Q

Epidural anesthesia : Horizontally, medication spreads to the ____ ____, where it diffuses into the CSF and achieves analgesia/anesthesia

A

dural cuffs

165
Q

Epidural anesthesia: Longitudinally, medication spreads in a ______ direction, with possible site of action along the paravertebral nerve trunks, intradural spinal roots, dorsal and ventral spinal roots, the dorsal root ganglia, the spinal cord, and the brain.

A

Cephalad

166
Q

Epidural anesthesia is ______ dependent

A

diffusion

167
Q

Relatively large volumes of local anesthesia must be used to achieve anesthesia. How much is used for an epidural?

How much is used for a spinal?

A

20 ml

2-3 min

168
Q

Epidural Anesthesia takes significantly longer to achieve because medications get to the subarachnoid space by the process of

A

diffusion

169
Q

The needle should always enter the epidural space in the _____ irregardless of approach used for access, as the space is widest here and the risk of puncturing epidural veins, spinal arteries, or spinal nerve roots is decreased.

A

midline

170
Q

Technique for lumbar epidural:

Use a long, 25 gauge needle to infiltrate local into the ______ and _____ ligaments.

Advance epidural needle through the supraspinous and interspinous ligaments in a slightly cephalad direction until it comes to lie within the “rubbery” ______ _______

Use either the loss of resistance technique or the hanging drop technique to locate the _____ _____

A

supraspinous and Interspinous

ligamentum flavum

Epidural space

171
Q

Technique for thoracic epidural:

Used to provide anesthesia for upper _____ and _____ regions.

Requires _____ dose of local anesthetic.

Placement considerations are similar to those for lumbar epidural.

Insert epidural needle in a more cephalad direction due to sharp ______ angulation of the thoracic vertebral spinous processes.

A

abdominal and thoracic

smaller

downward

172
Q

Epidural test dose:

A test dose of local anesthetic is given to verify correct needle location.

The test dose consists of ___ of local with ______

This will have little effect if placed in the epidural space.

If placed in the CSF, will rapidly behave like a spinal. What symptoms?

If injected into an epidural vein, a ______ increase in HR will be seen.

A

3 ml local, 1:200,000 epi.

numb, heavy legs

20-30%

173
Q

Does positioning have an effect on epidural blockade?

A

NO, it is not placed in the CSF

174
Q

For an epidural block, all solutions should be injected in increments of ____ ml, every 3 minutes and titrated to the desired anesthetic level. With loading doses and intermittent injections, _______ of the catheter should occur before any injection.

A

3-5

aspiration

175
Q

Addition of epi 1;200,000 to 1:400,000 solution ______ systemic uptake, resulting in lower plasma levels of the local anesthetic and _______ of its duration of action.

A

slows

prolongation

176
Q

Sympathetic nervous system blockade with epidural spinal.

Onset of sympathetic block is slower with decreased incidence of abrupt ____

A

hypotension

As with spinal anesthesia sympathetic block can result in a reduction in preload, a decrease in cardiac output and a decrease in BP.

177
Q

Side effects of epidural spinal

A

Backache
Post dural puncture headache PDPH
Trauma with catheter removal

PDPH is 1-2% , inadvertent tear of dura by 17g touhy needle makes a large dural perforation and is referred to as a “wet tap” , when a wet tap happens the rate of PDPH increases to 75%

APA 1 (7 decks)

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