Wk 7: Neuraxial Anesthesia Flashcards by Ashley Campbell

How many vertebra?
Cervical?
Thoracic?
Lumbar?
Sacral?
Coccyx?

33 vertebrae
Cervical: 7
Thoracic: 12
Lumbar: 5
Sacral: 5 (fused)
Coccyx: 4 (fused)

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What structures/ligaments do you pass through with a midline approach for an EPIDURAL (6)

Skin
Subcutaneous fat
Supraspinous ligament
Interspinous ligament
Ligamentum flavum
Epidural space

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What ligaments do you pass through with a paramedian approach?

Ligamentum flavum

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What area in the vertebral column in the needle inserted?

Midline approach
Paramedian approach

Midline approach: Directly midline between the spinous processes (intervertebral space)

Paramedian approach: Intervertebral space, lateral to the spinous process

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Where does the spinal cord and dural sac end in adults? In the infant?

Adult
Spinal cord: L1/L2
Dural sac: S2
Infant
Spinal cord: L3
Dural sac: S3

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How much CSF is produced every day by the choroid plexus?

500 ml every day
(25ml/hour)

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How much CSF is in circulation?

125-150 ml in circulation

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How much CSF is in subarachnoid space? (T11 downward)

30-80ml

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Where is CSF produced?

Choroid plexus in the lateral, third, and fourth ventricles

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Trace the flow of CSF from production in choroid plexus in the lateral, third, and fourth ventricle

Flows though the Foramina of Munro to the the third ventricle
To the aqueduct of Sylvius to the fourth ventricle
The fluid then passes through the foramina of Magendie and Luschka of the fourth ventricle to reach the subarachnoid space of the brain
It then spreads through the subarachnoid space over the surface of the spinal cord

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Area of skin that connects to a specific nerve root on your spine

Dermatome

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What structures/ligaments do you pass through with a midline approach for a SPINAL

Skin
Subcutaneous tissue
Supraspinous ligament
Interspinous ligament
Ligamentum flavum
Epidural space
Dura mater
Subdural space
Arachnoid mater
Subarachnoid space

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Sensory level required for:

Upper abdominal surgery
C- Section
Cystectomy

T4 (Nipple line)

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Sensory level required for:

C-section

T4 (nipple line)

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Sensory level required for:

Lower abdominal surgery
Appendectomy

T6-T7 (xiphoid process)

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Sensory level required for:

Total hip arthroplasty

T10 (Umbilicus)

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Sensory level required for:

Total hip arthroplasty
Vaginal delivery
TURP

T10 (Umbilicus)

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Sensory level required for:

Lower extremity surgery

L1-L3 (Inguinal ligament)

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Sensory level required for:

Foot surgery

L2-L3

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Sensory level required for:

Hemorrhoidectomy

S2-S5

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Cutaneous innervation of Nipple line is from spinal nerve root ___

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Cutaneous innervation of Xiphoid process is from spinal nerve root ___

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Cutaneous innervation of Umbilicus is from spinal nerve root ___

T10

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Cutaneous innervation of Pubic symphysis is from spinal nerve root ___

T12

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Cutaneous innervation of Anterior knee is from spinal nerve root ___

Dermatomes C3, 4, 5 significance

Phrenic nerve "C3, 4, and 5 keep the diaphragm alive"

Dermatomes C8 significance

All cardioaccelerators blocked (5th digit numb)

Dermatomes T1-4 significance

Some cardioaccelerators blocked

Dermatomes T4 significance

Nipple line

Dermatomes T6 signifiance

Xiphoid

Dermatomes T10 significance

Umbilicus

Order of blockade (spinal)

Autonomic Temperature Pain Touch Deep pressure Motor

Tests for sensation/sensory block (temperature) This is the ______ sensory modality blocked

Cold spray Ice cubes Alcohol pad First

Tests for sensation/sensory block (pain) This is the _____ sensory modality blocked

Tongue blade (broken off end) Stylet of epidural needle or blunt needle tip Nerve stimulator Second

A-alpha fibers function

Motor

A-beta fibers function

Touch and pressure

A-gamma fibers function

Proprioception

A-delta fibers function

Fast pain and temperature

B fibers function

Preganglionic, autonomic

C fibers function

Slow pain and temperature

Epidural vs. spinal dose

Epidural: High (10-20ml) Spinal: Low (1.5-2ml)

Epidural vs. spinal onset

Epidural: Slow (25-30 min) Spinal: Fast (5 min)

Epidural vs. spinal neuromuscular block

Epidural: Does not cause significant neuromuscular block Spinal: Does cause significant neuromuscular block

Epidural vs spinal multiple dosing possible?

Epidural: Multiple doses possible Spinal: Single dose only

Epidural vs spinal injection sites along backbone

Epidural: Can be given at various points along backbone Spinal: Can only be given at specific points along backbone to avoid damaging spinal cord (Below L3)

Epidural vs. Spinal needle

Epidural: Bigger needle (17 G Tuohy) Spinal: 25 G

Epidural injection site

Epidural space

Spinal injection site

Subarachnoid space

Epidural primary determinant of spread

Volume

Epidural requires ________ epidural catheter

Indwelling

Epidural is _____ dense than spinal

Less

Epidural site of action

Diffuse through the dural cuff migrating to nerve roots

Spinal site of action

Myelinated pre-ganglionic fibers of spinal nerve roots

Common complication of epidurals

PDPH (Post-Dural Puncture Headache)

Spinal primary determinant of spread (when using hyperbaric solution)

Baricity of LA

Spinal primary determinant of spread (when using hypo or isobaric solution)

Dose

Sensory level block in spinal anesthetic is ________ levels higher than motor block

2 levels

Sympathetic/autonomic level block in spinal anesthetic is _____ levels higher than sensory block

2-6 levels

Is there autonomic/sympathetic blockade in epidurals?

No Shouldn't cut off cardioaccelerators Unless you position patient flat and dose her too high for a C-Section

_______ is the main determinant of how LA is distributed when injected into the CSF (Spinal)

Baricity

Hyperbaric solutions have a ______ weight relative to CSF, and therefore are more _______. They will ______

Heavier Dense Fall/sink

Isobaric solutions have the ______ weight relative to CSF, and therefore an _____ density

Same Equal

Hypobaric solutions have a ______ weight relative to CSF, and therefore a ____ density. They will _____

Lighter Lesser Rise

Bupivacaine 0.75% in 8.25% dextrose Lidocaine 5% in 7.5% dextrose Tetracaine 0.5% in 5% dextrose Procaine 10% in water Types of solutions?

Hyperbaric

Bupivacaine 0.5% in saline Bupivacaine 0.75% in saline Lidocaine 2% in saline Tetracaine 0.5% in saline or water Types of solutions

Isotonic

Bupivacaine 0.3% in water Lidocaine 0.5% in water Tetracaine 0.2% in water Types of solutions

Hypobaric

Procaine 10% in water is an exception to the rule but is a _______ solution

Hyperbaric

Baricity is the ratio of the density of the __________solution to the density of ________

Local anesthetic CSF

______ is added to solutions to make them hypobaric

Water

_______ is added to solutions to make them hyperbaric

Dextrose

_______ is added to solutions to make them isotonic

Saline

Spinal for hemorrhoidectomy Baricity Hyperbaric: _____ x 15 minutes, then turn ______

Sitting Prone

Spinal for hemorrhoidectomy Baricity Hypobaric: ______, prone (more difficult)

Jacknife

Factors that significantly affect spread of spinal anesthesia

CONTROLLABLE Baricity Patient positioning before and after block placement Dose Site of injection NON-CONTROLLABLE Volume of CSF Density of CSF

The aspiration of the injected volume back into the syringe followed by reinjection twice, with 0.5ml increases in each aspirated volume

Barbotage

Absolute contraindications (7)

Patient refusal Coagulopathy or bleeding diathesis Increased ICP Severe aortic or mitral stenosis Ischemic hypertrophic subaortic stenosis Severe hypovolemia Infection at the site of injection

Relative contraindications (7)

Preexisting neurological complications Peripheral neuropathies Demyelinating lesions Severe spinal deformity Hypertrophic obstructive cardiomyopathy Sepsis Uncooperative patient

Controversial contraindications (5)

Prior back surgery Prolonged operation Major blood loss Complicated surgery Maneuvers that compromise respiration

What is the risk of anticoagulation in neuraxial anesthesia?

Spinal hematoma

Avoid neuraxial anesthesia if platelets < ____________

100,000

Avoid neuraxial anesthesia if PT, aPTT, and bleeding time > ____ times normal value Normal PT: ____ -_____ seconds (extrinsic pathway) Normal aPTT: ____ -____ seconds (intrinsic pathway) Normal Bleeding Time: ____ -____ min

2 8.9-11.3 sec 25-38 sec 3-7 min

Alone, _______ _______ appear NOT to increase the risk of spinal hematoma

Herbal supplements

When combined with anticoagulants, herbal supplements _________ risk of spinal hematoma

increase

Gingko, stop _____ hrs Garlic, stop ____ days Ginseng, stop _____ hrs

36 hrs 7 days 34 hrs

Incidence of spinal hematoma d/t traumatic insertion is 1: _________ for epidural anesthesia and 1: ________ for spinal anesthesia

1:20,000 epidural 1: 29,000 spinal (higher in epidural d/t bigger needle)

Warfarin should be held _____ days before block placement Can remove catheter if INR < ______

5 1.5

Thrombolytic agents such as T-PA, streptokinase, alteplase, and urokinase are __________ _________ to neuraxial anesthesia

absolute contraindications

Is it ok to proceed with neuraxial anesthesia if patient is taking Ginko, Ginseng, or Garlic (inhibit platelet aggregation), but are not on any other blood thinning drugs?

Yes, ok to proceed with neuraxial anesthesia

COX-1 inhibitos (NSAIDS, Aspirin), ok to proceed with neuraxial anesthesia?

Yes, if patient has normal clotting mechanism and not on any other blood thinning agents

The primary function of the cauda equina is to send and receive messages between the lower limbs and the ______ ______, which consist of the ______, the _______, and the _______ _______ _______

pelvic organs bladder rectum internal genital organs

The cauda equina begins at _____ -_____ (conus medullaris, where spinal cord ends) and continues down as nerve roots

L1-L2

Serious neurological condition that occurs when the bundle of spinal nerves at lower end of spinal cord is compressed/exposed to high concentrations of LA

Cauda Equina Syndrome

Risk factors of Cauda Equina Syndrome

-5% lidocaine, spinal microcatheters -Lithotomy, knee arthroscopy -Inflammation d/t herniated disc

Treatment for Cauda Equina Syndrome

Supportive

S/S of Cauda Equina Syndrome

Severe back and butt pain that radiates to legs

Cauda Equina Syndrome develops within ____ -____ hours and persists ___-____ days

6-36 hours 1-7 days

The needle for neuraxial anesthesia goes through the ____________ between spinous processes

interspaces

A landmark to determine the midline is the _______ _________

Spinous process

A lumbar procedure is easier than a thoracic procedure because the spinous processes in the lumbar vertebra project __________, while the spinous processes in the thoracic vertebra project ________

posteriorly inferiorly

A landmark for neuraxial placement is _____ ______, which corresponds to the ____ vertebra. You feel for the top of the _____ ______

Tuffier's line L4 iliac crest

What ligaments do you pass through in a midline approach?

Supraspinous ligament Interspinous ligament Ligamentum flavum

What ligaments do you pass through in a paramedian approach? Needle angled at ____ degrees off midline, or ____cm lateral, ____cm inferior to the interspace

Ligamentum flavum 15 1cm 1cm

The sacrum has ____ fused vertebrae

Bony nodules that flank the sacral hiatus Result from the incomplete development of the facets

Sacral cornuea

The sacral hiatus coincides with ____, and results from the incomplete fusion of the laminae at ____

S5 S5

The sacral hiatus is covered by what?

Sacrococcygeal ligament

What provides a distal entry point into the epidural space?

Sacral hiatus

Position for caudal anesthesia

Lateral or prone

Caudal anesthesia Palpate the _____ _____ and ____- ____

Sacral hiatus Sacral cornua

Caudal anesthesia Needle advanced at ___ degrees until "pop" felt (__________ _________)

45 degrees sacrococcygeal ligament

Absolute contraindications for Caudal anesthesia (3)

Spina bifida Meningomyelocele of the sacrum Meningitits

Relative contraindications for Caudal anesthesia (5)

Pilonidal cyst Abnormal superficial landmarks Hydrocephalus Intracranial tumor Progressive degenerative neuropathy

Caudal anesthesia A dosage of ____ - ____mL/kg or 0.125-0.25% ___________ or ________ with or without ________ can be used

0.5-1.0mL/kg bupivacaine or ropivacaine epinephrine

Caudal anesthesia Opioids may also be added (e.g. ____-____ mcg/kg of _________), although they are not recommended for outpatients b/c of risk of delayed respiratory depression

50-70mcg/kg morphine

Caudal anesthesia Addition of ___________ will tend to increase the degree of motor block

epinephrine

Caudal anesthesia complications Incidence of _______ _______ - ________ _________ occurs more frequently following caudal epidural block

local anesthetic-induced seizures

Frequency of seizures in adults: ________ > _________ > __________

caudal > brachial plexus block > lumbar or thoracic epidural block

____ - fold increased incidence (0.69%) of local anesthetic toxic reactions with caudal epidural anesthesia than with lumbar or thoracic epidural anesthesia in adults

Neuraxial infection, complications (3)

Aseptic/septic meningitis Epidural abscess Arachnoiditis

Factors that increase risk of infection (6)

Breaking aseptic technique Psoriasis DM HIV/immunosuppression Herpes Steroid therapy

For aspetic technique, how long wash hands?

20 seconds

For aseptic technique, surgical cap for _______ and _______

provider and patient

For aseptic technique, mask which covers both ____ and _____ Sterile _____ and _____ No ____ ____ in the field

nose and mouth prep and drape ID tags

Systemic effects of neuraxial anesthesia (6)

Vasodilates arterial and venous vessels (hypotension, bradycardia) Accessory muscle function is decreased Impairment of intercostal muscle (impairs ability to cough) Loss of proprioceptive input from chest (dyspnea) Reduces sensory input from reticular activating system (drowsiness) Inhibits afferent pathways (decreases stress response)

Tuffier's line/Jacoby's line/intercostal line

Straight line drawn between the iliac crests; usually crosses at level of L4 spinous process

How many times clean back with antiseptic solution?

3 times

Intraoperative risks (8)

Inability to obtain adequate anesthesia Paresthesia Hypotension Dyspnea High or total spinal N + V Use of additional sedation Allergic reactions

Unexpected cardiac arrest Patient population

Usually young, health patients (increased baseline vagal tone)

Unexpected cardiac arrest __________ response to neuraxial blocks

Physiologic

Unexpected cardiac arrest Gradual downtrend in ________ followed by severe _________ and/or _______

Heartrate bradycardia and/or asystole

Unexpected cardiac arrest SAB cardiac arrest can occur _____-____ minutes after insertion

20-60

Unexpected cardiac arrest Frequently associated with ___________ and __________

intraop blood loss orthopedic cement placement

Strategies to prevent and treat spinal induced hypotension (SIH) (4)

-Crystalloid/colloid solution (15ml/kg, 15 min before procedure). 0.5-1 L -Vasopressors -Positioning -5-HT3 antagonists (Zofran)

Postoperative risks (5)

Wet tap: PDPH Sepsis Neurological problems Backache Hematoma

High spinal = spread of LA block affecting the spinal nerves above _____. The effects will depend upon the nerves involved.

High spinal s/s

Bradycardia and SOB

Total spinal = intracranial spread of LA resulting in ______________

loss of consciousness (need to intubate)

Cardiovascular effects (5)

-Decreased SV (Peripheral fibers, T1-L2) -Decreased HR (Cardioaccelerator fibers, T1-T4) -Venous pooling -Decrease in venous return -Bezold-Jarisch reflex

Important tips for SAB Only use _______________ solutions Use __________ when drawing up solutions

preservative free filter needle

Important tips for SAB ____________ "wash", ___ -____mg prolong duration of block Additions of opioids enhance quality of block. (Duramorph____ -_____ mg or fentanyl ___ - ___mcg

Epinephrine, 0.1-0.2 mg 0.1-0.25mg 10-25mcg

Important tips for SAB If block doesn't spread cephalad to level adequate for C-section, may ask patient to _________

cough (However, the assumption that transient increases in CSF pressure or straining increase the spread of LA in the CSF is not supported by data)

Auditory, ocular, and facial complications (3)

Transient hearing loss Retinal hemorrhage Horner syndrome

Transient hearing loss and retinal hemorrhage cause by

changes in CSF pressure -postdural puncture leaks or large volumes of epidural injection

Horner syndrome (4)

ptosis miosis anhydrosis enophthalmos

Horner syndrome is caused by:

high spread of LA to sympathetic fibers to the head and neck (cranial nerve V)

LA for SAB hyperbaric

Bupivacaine 0.75% with 8.25% Dextrose (2ml vial)

Primary site of action for spinal anesthesia

myelinated preganglionic nerve roots within the spinal cord

Primary site of action for epidural anesthesia

LA diffuses through dural cuff

Epidural dose of morphine

2-5 mg

How long dose morphine last?

6-24 h

Additives

-Vasoconstrictors (epinephrine, phenylephrine) = prolongs DOA -Alpha-2 adrenergic agonists (clonidine) = Enhances pain relief and prolongs sensory and motor block

Distance from skin to epidural space: Average adult: ______ Obese adult: ______ Thin adult:_____

4-6 cm 8 cm 3 cm

Distance from skin to epidural space midline approach average:

5 cm

Largest epidural space

Mid-lumbar: 5-6 cm

Venous plexus within the epidural space

Batson's Plexus

_______ and _______ make Batson's Plexus more engorged, increasing risk of blood in needle or catheter

Obesity and pregnancy

Checking lumbar landmarks, 2 landmarks

Iliac crest Spinous process

Paramedial appraoch is ____ degrees off midline ___cm lateral and ___cm inferior

15 1 1

Taylor approach to paramedian technique is performed at ____ -____ interspace Spinal needle is inserted in a cephalo-medial direction through a skin wheal raised 1cm _______ and 1cm ________

L5-S1 medial, caudal

Thoracic epidural for thoracotomy

T4-T8

Thoracic epidural for Upper abdominal

T6-T9

Thoracic epidural for Renal

T7-T10

Thoracic epidural for Colorectal

T8-T10

Most common needle for spinal is: Most common needle for epidural is:

25 G Whitacre 17G Tuohy

Skin wheal is: ___ml of ___% _________

3 ml of 1% lidocaine

Epidural test dose

3ml 1.5% lidocaine with 1:200,000 epinephrine

Skin prep Betadine, leave on minimum ___ minute. Wipe with gause

Skin prep Chloraprep 0.5% (dry for ___ min). has _________ + ________

3 min chlorhexidine and alcohol

Skin prep Most effective agent

Chlorhexidine prep 0.5% not FDA approved

Needle direction for local infiltration Bevel orientation

15-30 degree angle Bevel up

If a catheter must be withdrawn while the needle remains in situ, both must be carefully withdrawn _____

together

If catheter breaks off within the epidural space, many experts suggest

leaving it in and observing the patient

If the catheter breaks off in superficial tissues, the catheter should

be surgically removed

Catheter insertion beyond needle tip should be ___ -___ cm

3-5 cm

"Funny bone sensation" down one or both legs signifies what

catheter brushing by a nerve root as it is passing into epidural space

Ultrasound epidural placement indications

Scoliosis Obesity Difficult insertion

Ultrasound epidural placement Probe

Curved linear Low frequency (2-5 MHz)

Ultrasound epidural placement Spinous process will appear __________ (hypoechoic, hyperechoic, anhoic)

hyperechoic

Ultrasound epidural placement Identifies epidural space_________ and ______

depth and position

Ultrasound epidural placement con

Limited data on spinal sonography and how to interpret images

Epidural drugs, spread, block levels Dose = _______ x ________

volume x concentration

Epidural drugs, spread, block levels Site of injection ( ______ to ______mL per segment)

1.25 to 1.5 mL

Epidural drugs, spread, block levels Height (_________ or _______)

extremely short or tall

Epidural drugs, spread, block levels Age (spread 3-4 x greater in _______) Limits LA to ____ to ____ mL per segment

Elderly 0.5 to 1 mL

Epidural drugs, spread, block levels Weight ( _______ _______)

Morbidly obese

Epidural drugs, spread, block levels Patient _________ during injection

position

Epidural drugs, spread, block levels Pregnancy (spread _____ in pregnancy) Limit LA to ____ to ___mL per segment

increases 0.5 to 1.0 mL

Epidural drugs, spread, block levels Speed of injection (rapid speed _______ spread)

does NOT

Epidural LA dosing All solutions should be injected in increments of ___ to ____ mL every ____ minutes and titrated to the desired anesthetic level

3 to 5 mL 3 minutes

Epidural drugs, spread, block levels ___________ of the catheter should occur before any injection ___________ dosing or a continuous infusion

Aspiration Intermittent

Epidural drugs, spread, block levels Continuous infusions typically use a ______ concentration of LA solution (______% to ______ bupivacaine or ____% to ____% ropivacaine)

lower 0.0625% to 0.125% 0.1% to 0.2%

Epidural opioids Crosses from the epidural space through the dura (via diffusion) to reach the opioid receptors located in the __________ __________ in the spinal cord

substantia gelatinosa

Epidural opioids To achieve adequate analgesia from epidurally administered opioids, the dose is increased by approximately ____ times the opioid dose administered intrathecally

Epidural opioids Rate of absorption is dependent on individual pharmacokinetics and ______ ______ of the opioid

lipid solubility

Epidural opioids A faster onset and analgesic peak effect is achieved when a more _______ opioid is used versus an opioid that is more ________

lipophilic lipophobic

Epidural opioids can be administered by either a single bolus dose or a __________ infusion

continuous infusion

Epidural test dose If intrathecal s/s

Immediate warmness of feet Leg weakness

Epidural test dose If intrathecal, what do you do?

STOP injection Restart at another level

Epidural test dose If intravascular s/s

HR increase 20% (or > 30 bpm above baseline within 30 secs) Ringing in ears Metallic taste in mouth Numbness of lips/face

Epidural test dose If intravascular, actions you would take

STOP injection Restart at another level

SE from neuraxial opioids (4)

Pruritus (most common) Respiratory depression Urinary retention (most common in young males) N/V

Treatment for opioid induced pruritus

Narcan Benadryl Nubain

Management of epidural anesthesia, inadequate block Resposition patient with _______ side down (dependent) or by administering ________________

unblocked more LA

Management of epidural anesthesia, inadequate block Single-sensory dermatome failed (Studies have shown that using __________ during the loss-of-resistance technique may be a contributing factor in missed dermatomal spread of the LA)

Air

Would you do an epidural in someone with a recent tattoo?

________, _________, or __________ at a desired epidural site is a contraindication to placement

Redness, irritation, or infection

Restlessness, dizziness, tinnitus, perioral paresthesia, difficulty speaking, seizures, LOC

Intravascular injection (1:5000)

Agitation, profound hypotension, bradycardia, dyspnea, the inability to speak, and loss of consciousness. T1-T4 blockade.

Intrathecal injection (1:2900)

What do you document in chart after epidural catheter is removed?

That tip is intact on removal

What happens if epidural catheter tip breaks off, and patient is asymptomatic?

Inform patient Document in chart Leave it in

What happens if epidural catheter tip breaks off, and patient is symptomatic

Order an MRI Consult neurosurgery

CSE two-level technique Each component is performed _______ at ____ different interspaces

separately two

CSE two-level technique An _________ _______ is inserted first, followed by a ___________ anesthesia needle placed one or two interspaces lower

epidural catheter spinal

CSE two-level technique Primary advantage

Ability to insert and test the epidural catheter first, then place the spinal anesthetic needle

CSE two-level technique cons Inability to differentiate the _______ ____ ____ from the CSF An increased risk of _____ _______ by the epidural catheter

epidural test dose dural puncture

CSE: Single level technique A small (25, 27, or 29 G) ______ -point spinal needle is inserted through the epidural needle into the subarachnoid space, and LA is injected The spinal needle is removed, and an ________ catheter is threaded into the epidural space. The epidural needle is removed and the catheter is secured

pencil epidural

Incidence of PDPH

0.2%-24%

PDPH Decreased ______ volume/pressure in subarachnoid space, meninges stretch

CSF

PDPH factors that increase incidence (5)

Large, non-pencil point needle Cutting needle bevel direction (perpendicular) Multiple punctures Female Age <40

PDPH occur within ________ hours to ____-____ postop day

several hours to 1st-2nd

PDPH HA is positional: relieved when patient __________

lying down

PDPH conservative treatment (7)

-Horizontal position -Oral analgesics -Adequate hydration -IV caffeine (500mg): shown to eliminate HA in 70% -Oral caffeine (300mg) -Theophylline: 150mg q12h -Sphenopalatine ganglion (SPG) block

SPG block Soak a long cotton tipped applicator in ___ - ____% __________ or ____% bupivacaine solution

1-4% lidocaine 0.5% bupivacaine

SPG block Patient in ___________ position Insert applicator into each nare, toward _______ __________ Leave applicator in for ___ -____ minutes

sniffing middle turbinate 5-10

Definitive treatment for PDPH

Epidural blood patch

When should you consider an epidural blood patch?

Conservative treatment first, then after 24 h

Epidural blood patch works by _____ formation that seals the dura and _____ CSF pressure

clot increases

How long does it take for relief after epidural blood patch?

Usually intantaneous

The success rate of an epidural blood patch is increased if performed _____ hours after dural puncture

If epidural blood patch failed, when can you repeat?

in 24 h

If epidural blood patch failed x 2?

Seek alternative diagnosis

Epidural blood patch Insertion site

At same level or 1 level below level of the lowest initial needle insertion

Epidural blood patch Draw _____ mL patient's venous blood from IV or 1 time AC blood draw

Epidural blood patch After ______, inject blood into space

LOR

Epidural blood patch Injection proceeds until patient senses pressure in _____, ______, or ________ _____ - _____ mL

back, buttocks, or legs 12-15 mL

Epidural blood patch Patient to remain supine ___ mins to ____ hour after procedure

30 mins to 1 hour

Wk 7: Neuraxial Anesthesia Flashcards

(236 cards)