CSE

Question 1

CSF total volume between brain and spinal cord :

Answer 1

140-150cc at any one time in the entire system (between 30-80cc in the Spinal Cord

Question 2

The pH of the CSF is approx.

Answer 2

7.32

Question 3

CSF is secreted by ……….at a rate of …………

Answer 3

It is secreted by EPENDYMAL cells of the Choroid Plexus within the ventricular system at a rate of 30cc/hr (500 total daily).

Question 4

Your entire volume of CSF is replaced once every

Answer 4

3-4 hour

Question 5

CSF pressure

Answer 5

10-20 cm H2O

Question 6

the primary site of action of the Local Anesthetics, both with Spinals AND Epidurals.

Answer 6

The NERVE ROOT is the primary site of action of the Local Anesthetics, both with Spinals AND Epidurals. The only difference is WHERE the root is being anesthetized, either Subarachnoid or in the Epidural space

Question 7

Advantages

of spinal

Answer 7

• Simple
• Predictable
• Fully conscious patient
• Analgesia into the post-op period
• Ideal for lower abdomen, pelvis/ perineum, and lower extremities
• Reduces risk of DVT
• Use small dose of LA, less toxicity

Question 8

Disadvantages of spinal

Answer 8

-Sympathetic blockade 100% of the time
Hypotension
-Intense motor blockade
*May last for hours post-op
-Surgeons complain “It takes to long”

Question 9

differential block epidural vs spinal

Answer 9

epidural More pronounced differential block or a segmental block

Question 10

epidural test doses

Answer 10

• All epidural doses are test doses
• All should be injected in increments of 3 to 5 mL
• Every 3 minutes and titrated to the desired anesthetic level

Question 11

epidural dosing

Answer 11

Volume is the key factor in the height of the block

Question 12

factors affecting epidural?

Answer 12

• NOT related to Baricity,
• Position:
• Larger volume larger vertical spread
• Increased LA concentration will produce faster block and more intense block

Question 13

Advantage of CSE

Answer 13

• CSE anesthesia and analgesia offers the advantages of both spinal and epidural techniques while reducing or eliminating the associated disadvantages (Sort of)
• Appropriate in all settings in which anesthesia provider plans on doing a spinal or epidural anesthesia
• Takes advantages of each: quick onset of spinal and flexibility of epidural catheter

Question 14

Two-level Techniques

Answer 14

• The two-level technique is unique in that each component is performed separately at two different interspaces
• Epidural needles placed first, followed by a spinal needle placed one or two interspaces lower

Question 15

Advantage of technique

Answer 15

• Ability to insert & test the epidural catheter first then place the spinal anesthetic needle
• Once spinal in in place no delay when positioning patient-this could be very important when using hyperbaric SAB

Question 16

Potential problems CSE

Answer 16

• Inability to distinguish the epidural test dose from CSF
• Epidural catheter laceration by the spinal needle
• Inability to get CSF because of compression of the dural sac by the test dose
• Increased risk of dural puncture by epidural catheter

Question 17

Disadvantages CSE

Answer 17

• Increased discomfort- 2 sticks
• Tissue trauma
• Morbidity associated with multilevel Interspinous space penetration
• Hematoma
• Technical difficulties

Question 18

Single-Level Technique

Answer 18

• Needle-through-needle
• This technique involves insertion of an epidural needle at the appropriate interspace and then using the epidural needle as a guide for the spinal needle
• A small 25,27 or 29 g pencil-point needle
• Inserted through the epidural needle into subarachnoid space and LA is injected

Question 19

Needle-Through-Needle

Answer 19

• Spinal needle is then removed
• Epidural catheter is threaded into the epidural space
• Epidural needle removed and catheter is secured

Question 20

Advantage of single level

Answer 20

• Only one puncture site
• Less tissue trauma
• Less Backache

Question 21

Disadvantage of single level

Answer 21

• Possible inadequate spinal block if catheter placement is delayed
• Inability to obtain CSF because of inadequate spinal needle length
• Possibility of catheter migration through the dural puncture caused by the introduction of spinal needle
• Inability to reliably test the catheter with preexisting spinal block

Question 22

Specialized Needles

Answer 22

• CSE developed with two channels
• One for the epidural catheter and the other for the spinal needle
• Tuohy needle was modified with a separate back-eye at the bend of the needle thereby permitting straight passage of spinal needle
• The spinal can miss the back eye and exit out the main orifice as occurs in the needle-through-needle technique

Question 23

CSE goal

Answer 23

Was developed to minimize the hypotensive effects of the spinal component of CSE for C/S

Question 24

CSE technique

Answer 24

-A epidural needle is placed at the selected interspace LOR with AIR
-Then a low-dose 0.75% hyperbaric bupivacaine SA
is placed using the needle-through-needle technique
-Spinal needle removed catheter is inserted and taped in place
-Patient then placed on LUD in OB

Question 25

CSE CONTINUED

Answer 25

After 15 minutes the block is extended by titrating epidural LA until the desired level varies for what level: Lumbar 1-2 mL per segments Each dose is always a test dose with _______ mL

Question 26

CSE TECHNIQUE

Answer 26

- This technique takes longer it has been shown to decrease the frequency and severity of the hypotension seen with spinal anesthesia - Used in other types of surgery also besides OB

Question 27

CSE AGENTS

Answer 27

- Any combination of medications appropriate for spinal and epidural anesthesia - Combination of opioids such as morphine & fentanyl

Question 28

Management of CSE Anesthesia

Answer 28

- Use of intrathecal fentanyl and ambulation - CSE- associated with faster onset, denser motor block, lower anxiety and lower preoperative and intraoperative pain scores and better patient satisfaction

Question 29

Failure to obtain subarachnoid block

Answer 29

- Fail rate for single level CSE technique 0%-24.5% - Fail rate for two-level technique 1.6%-4% - Important consideration is length of spinal needle that extends beyond the tip of epidural needle-studies have shown increased success rate when spinal needle extends 0.7-1.5 cm beyond epidural tip - Needle exits standard Tuohy needle tip, this angle may be 4 to 5 degrees or more

Question 30

Total/ High Spinal symptoms

Answer 30

- Dural puncture - Symptoms are Rapid and dramatic: * Sudden and extensive motor blockade, inability to talk progresses to apnea, unconsciousness, severe hypotension and dilated pupils * Treatment controlled ventilations, ETT, 100% oxygen and cardiac support * Subdural block-similar to high spinal but slower onset

Question 31

Increased Spinal Level After Epidural Administration

Answer 31

The CSE is know to cause an increased spread of spinal anesthesia after injection of solution through the epidural catheter

Question 32

PDPH

Answer 32

- Controversy of higher risk of PDPH - If in sitting position and midline placement of the epidural needle. Sitting provides for higher hydrostatic pressure more likely for CSF - Pencil point needle utilized

Question 33

Infection

Answer 33

- Incidence of infection complications associated with epidural and spinal very low 0% to 0.04% - Several studies site bacterial meningitis associated with CSE - Because CSE involves first inserting into epidural space then subarachnoid space - Strict aseptic technique should always be practiced

Question 34

NEUROLOGIC INJURY

Answer 34

- Very low risk same as spinal and epidural - Paresthesia during epidural catheter placement range from 20% to 44%. A preexisting spinal block may mask as significant paresthesia on catheter insertion and result in neurologic injury