8. A single injection of a local anesthetic
solution into the subarachnoid space usually
at the lumbar level
Intrathecal Narcotics
Commonly at L3-L4
Largest Interspace
L5-S1
9. Small needles PDPH
Large needles improve
tactile sensations
Pencil-point needles
PDPH risk
Further reduction with
addition of ITN
Side injection needles with
large holes CSF but
careful to have entire hole
subarachnoid
10. Baricity of anesthetic solution
Position of the patient
During injection
Immediately after injection
Drug Dosage (mg)
Concentration times volume
Addition of Opioids
Site of Injection
14. Isobaric – Stays where you put it
LA has the same density or specific gravity as CSF (1.003-
1.008) – Normal Saline
Hypobaric – “Floats” up – Lighter than CSF
LA has a density or specific gravity that is less than CSF
(<1.003) – Sterile Water
Hyperbaric – Settles to Dependent aspect of the
subarachnoid space – Heavier than CSF
LA has a density or specific gravity that is greater than CSF
(>1.008) - Dextrose
15. Sitting
With Legs hanging over side of bed
Have the patient hug a pillow
Put Feet up on a Stool (no wheels)
Assistant MUST keep the patient from Swaying
Curve her back like a “C”, Halloween Cat, Shrimp,
Cannon ball
Up in the Bed (quicker but not optimal)
Baricity?
Lateral Decubitus (Left or Right?)
Needs to be Parallel to the Edge of the Bed
Legs Flexed up to Abdomen
Forehead Flexed down towards Knees
Jack-knife Position
Chosen for ano-rectal surgery
CSF will not drip from hub of needle
Use hypobaric solution
Bupivacaine less run-off than lidocaine
17. Midline
Most commonly used
As needle passes thru the
dura mater a “pop” is often
appreciated
CSF flows thru once stylet is
used
For small gauge needles (26-29
g) this may take 5-10 seconds
May take even longer in
dehydrated or elderly patients
If no CSF flow, needle can be
obstructed by a nerve root
(rotate 90 degrees)
18. After identifying the proper
interspace palpate the
spinous process
Insert needle 1 cm lateral
and 1 cm inferior to this
point and direct needle
towards interspace
May need to walk medially off
of transverse process
Ligamentum flavum is
usually the first resistance
indentified
Bypasses supraspinous and
intraspinous ligaments
Traditional
Taylor (L5-S1)
19. GIVE INTRAVENOUS FLUID BOLUS OF 500 CC
PRIOR TO SAB/EPIDURAL DOSE.
If it is not a labor epidural/c-section, give
versed, fentanyl and oxygen prior to neuraxial
anesthesia.
Local Anesthetics to the skin, deep tissues?
Skin wheal should be performed at vertebral interspace (1-2
ml) and to adjacent sides (.5ml) with 1% Lidocaine
20. Unable to locate CSF
Inability to enter SA space
If bone (os) encountered superficially
redirect needle cephalad
If bone (os) encountered deep
redirect needle caudally
Inability to aspirate CSF before injection
Ensure that you have CSF in all 4 planes
Surgery outlasting the drug selected
Short, intermediate & long term local anesthetics
Can increase duration & efficacy with opioids/LA admixture
5-10 mcg fentanyl or 1-2 mcg sufentanil
Dose (mg) Duration
T-10 T-4 Plain w/epi (0.2 mg)
Lidocaine 30-50 mg 75-100 mg 45-60 min 60-90 min
Tetracaine 6-10 mg 12-15 mg 60-90 min 120-180 min
Bupivacaine 6-10 mg 12-15 mg 90 min 140 min
Ropivacaine 6-10 mg 12-15 mg 90 min 140 min
21. Drug Dose
Onset
(min)
Peak effect
(min)
Duration
(hrs) Advantages Disadvantages
Morphine
0.1-0.25
mg 30 60 12-24
Long duration
Significant side
effects; delayed
respiratory
depression;
biphasic modality
Fentanyl 10-25
mcg
5 10 2-3 Rapid onset Short duration
Sufentanil 5-10 mcg 5 10 2-4
Rapid onset;
few side
effects
Short duration; can
see sinusoidal fetal
HR; respiratory
depression >
fentanyl
Meperidine
10 mg
10 15 4-5
Rapid onset;
potentiation
of spinal
anesthesia
Nausea and
vomiting; pruritis
significant
22. Definition of determining level: analgesia versus
anesthesia
Alcohol skin wipe
Pinch
“toothpick” skin test
Nerve stimulator
Etc., etc., etc.
Beware: break no skin, use no needles
23. Work fast after local anesthetic injected
Assess early and frequently
Augment position changes to maximize spread hyper /
hypo baric solutions early
Co-administration of IT Opioids
? Make patient cough several times
More effective with lidocaine
24. Use previously discussed strategies
Re-do spinal anesthetic
Supplementation with local anesthetic per surgeon
Analgesic intravenous supplements
Dissociative intravenous supplements
General Anesthesia
25. Spinal Anesthesia Group
10-12 mg Hyperbaric Bupivacaine
Supplemental Anxiolysis & fentanyl
Intraarticular Group
IA Injection 15 min before incision by
anesthesia in holding
Followed customized format
2-injection technique
20 ml Bupivacaine 0.5% with epinephrine
(1:200,000)
Propofol Infusion
50-100 mg/kg/hr
Fentanyl supplementation
50-100 mcg during injection with 2 mg
midazolam
General Anesthesia Group
Standardized Induction
Desflurane or Sevoflurane
Time Requirements between Groups
SurgicalTim
e
A
nesthesia
Tim
eTO
TA
L
H
ospitalTim
e
0
100
200
300
400
500
600
Spinal
Intraarticular
General
*Sig p < .05
*
TimeinMinutes
(MeanSD)
Time from Surgical Start to
First Postoperative Analgesic Request
0
100
200
300
400
500
600
700
800
Spinal
Intraarticular
General
* *Sig p < .05
TimeinMinutes(SD)
26. Placement of Local Anesthetic into epidural
space
Dural Rent
27. Indications
Contraindications
Same as SAB (
? Tattoos
Epidural blocks can be placed 4 hrs after last dose of SQ Heparin, 12 hrs after
last dose of LMWH
NSAIDS (including ASA) not contraindicated
Placement relatively safe with INR < 1.5
Orthopedic Major hip/knee surgery, pelvic fractures
OB/GYN C-section; laboring analgesia/female pelvic organs
Urology Prostate, bladder procedures
General Surgery
*Thoracic vs Lumbar)
Upper & lower abdominal procedures* (height of block)
Postoperative analgesia, combination with GA to reduce requirements
Pediatric Procedures
(*usually through caudal)
Penile procedures, IHR, Ortho procedures; Postoperative analgesia,
combination with GA to reduce requirements
Vascular Surgery Vascular reconstruction, amputations
Thoracic Surgery
(*Thoracic epidural)
Postoperative analgesia, combination with GA to reduce requirements
Medical Conditions Known/suspected MH
28. Typically use Loss of Resistance Technique
Routinely placed in Lumbar region
Use the needle for skin infiltration to identify midline
structures
Insert the needle in a slightly cephalad direction
Dorsum of non-injecting hand rests on patient’s
back
Thumb and index finger grasp hub of needle
Seat needle into intraspinous ligament and
advance in slightly cephalad direction with
continuous pressure on plunger of syringe and
when the needle exits ligamentum flavum feel
sudden loss of resistance
The distance from skin to epidural space is 4-6 cm in
90% of the population
Never change the direction of the needle tip after it
passes through the ligamentum flavum
Do not advance the needle
Air versus Normal Saline
Missed dermatomes
Presence of parasthesias?
29. Thread catheter 3-5 cm
Check position
Presence of parasthesias?
Remove needle while keeping positive pressure on catheter (thread
concurrently)
Check position
Secure catheter
Check position
Test dose
Aspirate for Blood or CSF
Off midline insertion usually results in higher blood vessel puncture
A change of 20% or greater in HR after test dose indicates intravascular injection
(replace catheter)
A dense motor block within 5 minutes after test dose indicates spinal block (if
positive either replace catheter or convert to continuous spinal technique)
Only give test dose after contraction is over in pregnant women
If patient on beta blocker a change in systolic pressure > 20 mm Hg indicates
intravascular injection
1.5 % Lidocaine with epinephrine vs 2% Lidocaine
30. Problem Interpretation Reason Action
Needle floppy, angles laterally Missed intraspinous ligament Entry off midline Reassess and redirect needle
Hit bone < 2 cm on insertion Hit spinous process Missed interspace; spine flexion
inadequate
Identify interspace; redirect
needle more caudal
Hit bone > 4cm or > Contacted lamina Needle entry too lateral Redirect more midline or use
paramedian approach
Bony resistance all approaches Arthritic spine & ligaments Ossification of ligaments Use paramedian approach
Cannot thread catheter Narrow epidural space; Missed
epidural space, false loss of
resistance
Space not dilated
Epidural needle too close to dura;
catheter not in epidural space
Dilates space with 20 ml NS
Try rotating the needle slightly to
change bevel direction
Resistance to LA injection,
difficulty passing catheter, clear
fluid in catheter, cold fluid in
catheter
Drip back of LA Cold fluid = LA; may be in
subdural space
Can be widespread patchy block
with hemodynamic stability;
replace catheter and wait for
resolution
Pain (parasthesia) with catheter
insertion
Catheter near nerve root Approach too lateral; too much
catheter in epidural space
If pain persists replace catheter;
withdraw catheter if > 5 cm and
reassess
Can’t palpate spinous process Obesity or arthritis (obscuring
spinous processes)
Obesity; severe arthritis Try midline approach for obese
Use 22 g needle to identify bony
landmarks
Use paramedian approach
32. Volume is the key factor in determining height of blockade
Typical loading dose is 10-20 ml given in 5 ml increments
Wait about 2-3 minutes between increments
Use of epinephrine and bicarbonate will speed up onset on anesthesia
If block incomplete after bolus replace catheter rather than wasting time
giving larger dose or re-positioning catheter
Inject one-quarter to one-third of initial dose about 15 minutes after initial
bolus to enhance sensory blockade
Cookbook guideline
To determine volume you can use the 5-foot rule
Example: For an individual who is 5 feet in height you administer 1 ml of local anesthetic
solution for each segment requiring blockade and increase the volume by 0.1 ml for every 2
inches above 5 feet.
Example: For someone 5’10” in height and you enter at L3-L4 Interspace and want a to block up
to T-6.
8 ml for L3-S5 and 7 ml for L2-T6 = 15 ml (base amount)
Additional amount is 0.1 ml times 5 (10 inches/2) = 0.5 times 15 segments = 7.5
(supplemental amount)
Overall add the 15 ml plus the 7.5 ml to get a dose of 22.5 ml
Need a total of 22.5 ml to achieve a T-6 level on a 70” person
34. CSE technique
Allows for immediate relief of pain (from SAB) & subsequent
administration of medications via CLE for prolonged anesthesia
Advantages
Reported to decrease failure rates of CLE (confirmation of epidural
placement)
Clinical uses:
General Surgery
Laboring analgesia & Cesarean Section
High risk patients
Slower onset of sympathetic blockade
Careful positioning during SAB with subsequent titration of CLE
Administration of intrathecal opioids with small amount of
bupivacaine (2.5-5 mg) decreases epidural dosing requirements and
decreases degree of sympathectomy
35.
36. CSE offers the advantages of both spinal and epidural
anesthesia
CSE provides rapid onset and careful titration
Can use doses as low as 40 mg lidocaine or 7.5 mg bupivacaine
Additional Opioids
Sufentanil
Fentanyl
Morphine
Potential disadvantages
PDPHA
Catheter migration into SA space
Test Dose
Transient parasthesias
Ideal length of spinal needle beyond epidural needle is 12-13 mm
Longer spinal needles associated with higher incidence
