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1. REGIONAL ANESTHESIA PART 2
EPIDURAL ANESTHESIA

Bassim Mohammed Jabbar

MSc ansthesia & intensive care unit

2. EPIDURAL SPACE
Potential space between the dura mater and ligament flavum Made up of
vasculature, nerves, fat and lymphatic
Extends from foramen magnum to the sacrococcygeal ligament. Is
segmented and not uniform in distribution
The Bounds of the Epidural Space
Anterior- posterior longitudinal ligament, Lateral- pedicles and
intervertebral ligaments, Posterior- ligamentum flavum
Epidural level (cervical ,thoracic, lumber, Caudal)
 Widest at Level L2 (5-6mm)
 Narrowest at Level C5 (1-1.5mm
Distances from Skin to Epidural Space
Average adult: 4-6cm (80%)
Obese adult: up to 8cm
Thin adult: 3cm
Volume : 118ml

4. EPIDURAL ANESTHESIA CONTINUE
Indication and Contraindication:
The same of spinal anaesthesia.
Additional indication is the post operative Pain
management using the epidural catheter
technique.
Complications: the same of spinal anaesthesia,
except the post dural puncture headache.

5. EPIDURAL ANESTHESIA
Local anaesthetic solutions are
deposited in the peridural space
between the dura mater and the
periosteum lining the vertebral canal.
The injected local anaesthetic solution
produces analgesia by blocking
conduction at the intradural spinal
nerve roots.

7. SPREAD OF LOCAL ANESTHETIC IN THE EPIDURAL SPACE
Local anesthetic injected into the epidural
space moves in a horizontal and longitudinal
manner.
Theoretically the longitudinal spread
could reach the foramen magnum and sacral
foramina if enough volume was injected
Horizontally the local anesthetic spreads
through the intervertebral foramina to the
Dural cuff.
Local anesthetics spread through the Dural
cuff via the arachnoid villa and into the CSF.

9. TYPES OF EPIDURALS
There are two main types of epidurals
1. Regular Epidural (used by most women)
 Pumped or injected into your lower spine through a catheter
 Combination of opioids and anesthetics (given with the epidural to
decrease the required dose of local anesthetic)

10. Allows pain relief for 4-8 hours
2.

11. VOLUME
Can be variable
General rule: 1-2 ml of local anesthetic per dermatome
i.e. epidural placed at L4-L5; you want a T4 block for a C-sec. You have
4 lumbar dermatomes and 8 thoracic dermatomes. 12 dermatomes
X 1-2 ml = 12-24 ml
Dose of local anesthetics administered in thoracic area should be
decreased by 30-50% due to decrease in compliance and volume
Height
The shorter the patient the less local anesthetic required.
A 1 ml per dermatome while someone who is tall may require the full 2
ml per dermatome
Gravity
Position of patient does affect spread and height of local anesthetic
BUT not to the point of spinal anesthesia.
i.e. lateral decubitus position will “concentrate” more local anesthetic
to the dependent side will a weaker block will occur in the non-
dependent area.
A sitting patient will have more local anesthetic delivered to the lower
lumbar and sacral dermatomes

12. Sterile Technique is Essential!
Remember the continuous/direct
communication!

13. EPIDURAL SET
1.Syrange10ml
2.Tohy needle
3.Epidural catheter.
4.Filter.
5.connector.

15. EPIDURAL CATHETERS
Ideal Placement (adult) 10-12 cm at the skin
Epidural catheters have markings
that indicate their length.
= there is a mark at the tip of the catheter
= the 1st single mark up the catheter is 5cm
= double mark up the catheter is 10 cm
and so on
A change in depth of the catheter indicates migration
either into or out of the epidural space

16. INSERTION OF EPIDURAL CATHETER
Positioning of patient
The site is dependent upon the area of pain
Fixing the catheter
Incision Level
Thoracic T4-T6
Upper abdo T6-T8
Lower abdo T8-T10
Pelvic T8-T10
Lower extremity L1-L4

17. CATHETER MIGRATION
Catheter migration into a blood vessel in the
epidural space or subarachnoid space
rapid onset LOC
Decrease loss of sensory or motor loss (marcain)
Toxicity
Profound hypotension
Out of the epidural space
ineffective analgesia
no analgesia
drugs deposited into soft tissue.

20. EPIDURAL ANESTHESIA
Test Dose: 1.5% Lido with Epi 1:200,000
1.Tachycardia (increase >30bpm over resting HR)
2.High blood pressure
3.Light headedness
4.Metallic taste in mouth
5.Ring in ears
6.Facial numbness
Note: if beta blocked will only see increase in BP not HR
Bolus Dose: Preferred Local of Choice
10 milliliters for labor pain
20-30 milliliters for C-section

21. PAIN ASSESSMENT
Verbal numeric rating scales：
The patient is asked to rate pain on a numeric scale, usually
0–10, where 0 is no pain and 10 is the worst pain
imaginable
the Wong-Baker FACES Pain Rating Scale

22. MOTOR AND SENSORY ASSESSMENT
Sensory assessment:
* Use ice in the tip of a glove
* Start in upper neck and move down
thorax bilaterally assessing all
potential dermatomes
* Level of block is where intensity of cold
changes or the cold sensation is absent

23. MOTOR AND SENSORY ASSESSMENT
Bromag
e Score
Motor
assessmen
t

24. ASSESSMENT OF THE SEDATION
LEVEL
Alert
None
0
Easily aroused
Mild
1
Difficult to arouse
or RR <10
Moderate
2
Unresponsive or RR
<8
Severe
3

25. CAUSES OF BREAK THROUGH PAIN
1.Epidural catheter kinked or dislodged
2.Epidural catheter disconnected at filter
3.Epidural block is unilateral on the wrong side
4.Insufficient epidural infusion rate to cover
desired dermatomes
5.The epidural catheter tip is situated too high or
too low in the epidural space

26. CONSIDERATIONS IN CHOOSING
L.A DRUG.
*Understanding of local anesthetic potency &
duration
*Surgical requirements and duration of surgery
*Postoperative analgesic requirements
*Use only preservative free solutions
*Read the labels, ensure that it is preservative free
or prepared for epidural/caudal
anesthesia/analgesia

27. MEDICATION COMMONLY USED
OPIOIDS-Fentanyl +Morphine
(affect the pain transmission at the opioid
receptors)
L.A:
(inhibits the pain impulse transmission in the nerves
with which it comes in contact)
Short Acting L.A: 2-chloroprocaine
Intermediate ActingL.A: lidocaine and mepivacaine
Long ActingL,A: bupivacaine, etidocaine, ropivacaine,
levobupivacaine

28. SHORT ACTING
Intermediate Acting

29. LONG ACTING
Bupivacaine
Levobupivacaine

30. OPIOIDS
Mechanism of action-distribution
*Vascular uptake by blood vessels in the epidural space
*Diffusion through dura into CSF to spinal cord to the site of action.
*Uptake by the fat in the epidural space.

31. OPIOIDS
Morphine (Duramorph/Astramorph)
Hydrophilic(water soluble)
Slow to diffuse across the dura on to the spinal cord
Can cause late respiratory depression
Monitor respiratory status for 12 hrs after the last dose of
duramorph
Duration 6 hrs+
Broad spread

32. OPIOIDS
Fentanyl (preservative free)
Lipophilic(fat soluble)
Crossess the dura rapidly
Rapid onset of action(segmental)
Decreased risk of late respiratory depression
Onset 5-20 mins
Duration 2-4hrs
Excellent for breakthrough pain

33. ADVERSE EFFECTS -OPIOIDS
1.Sedation and resp.depression
2.N/V-Opioids stimulate the chemoreceptor trigger
zone
3.Pruritus- diphenhydramine or narcan (low dose)
4.Urinary retention- low dose narcan and /or
catheterization
5.Slowing of GI motility
6.Hypotension

34. LOCAL ANESTHETICS
AMIDES MAX / DOSE
BUPIVACAINE 2 MG/KG
LIDOCAINE 7 MG/KG
ROPIVACAINE 4 MG/KG
MEPIVACAINE 7 MG/KG
PRILOCAINE 6MG/KG

35. METHODS OF ADMINISTRATION
BOLUS (FENTANYL, DURAMORPH)
CONTINUOUS
INFUSION(MARCAINE+FENTANYL)
All drugs administered epidural should be
preservative free.
All epidural opioids should be diluted with normal
saline prior to intermittent bolus administration.

36. REGIONAL ANESTHESIA IN THE ANTICOAGULATED
PATIENT
Heparin: Reverse with FFP or Protamine
IV discontinue 4 hours prior to block
SQ can block one hour prior to dose
Do not D/C cath until 4 hours after heparin D/C’d & obtain normal lab
values
Plavix: No Reversal
Stop 5-10 days prior to surgery
NSAIDS: No Reversal
May be safe for regional block
Ideal to stop 5 days prior to surgery
Aspirin: No Reversal
Stop 7-10 days prior to surgery

37. Epidural dose
drugs
2-5 mg
morphine
2-3 mg
diamorphine
25-50 mg
pethidine
10-50µg
sufentanal
50-100µg
fentanyl
0.5-1.0mg/kg
ketamine
0-20μg/kg/hr
medazolam
1ml of 8.4% NaHCO3 per 10ml of
lidocaine
Sodium bicarbonate
5 μg/ml
adrenaline
postoperative pain: 50-100μg
labour analgesia: 300-500μg
neostigmine
75-150μg
clonidine
Epidural dose
Druge
2-5 mg
morphine
2-3 mg
diamorphine
25-50 mg
pethidine
10-50µg
sufentanal
50-100µg
fentanyl
0.5-1.0mg/kg
ketamine
10-20μg/kg/hr
medazolam
1ml of 8.4% NaHCO3 per 10ml of lidocaine
Sodium bicarbonate
5 μg/ml
adrenaline
postoperative pain: 50-100μg
labour analgesia: 300-500μg
neostigmine
75-150μg
clonidine
Drug use to increase the effecacy or potancy or decrease the side effect of
medication when given concurrently
Adjuvant agent in neuraxial blockade anesthesia

38. DIFFERENCES BETWEEN SPINAL AND EPIDURAL ANESTHESIA
Spinal anaesthesia Extradural Anaesthesia
Level: below L1/L2, where the spinal
cord ends
Level: at any level of the vertebral
column.
Injection: subarachnoid space i.e
punture of the dura mater
Injection: epidural space (between
Ligamentum flavum and dura mater)
i.e without punture of the dura mater
Identification of the subarachnoid
space: When CSF appears
Identification of the Peridural space:
Using the Loss of Resistance
technique.
Dosis: 2.5- 3.5 ml bupivacaine 0.5%
heavy
Doses: 15- 20 ml bupivacaine 0.5%
Onset of action: rapid (2-5 min) Onset of action: slow (15-20 min)
Density of block: more dense Density of block: less dense
Hypotension: rapid Hypotension: slow
Headache: is a probably complication Headache: is not a probable.

39. THANK YOU
Always make your patient comfortable